767:
whatever else is in the door's circuitry. Inspection of the circuit (either the diagram or the actual objects themselves—door, switches, wires, circuit board, etc.) might reveal that, on the circuit board "node 22" goes to +0 volts when the contacts of switch "SW_D" are mechanically in contact ("closed") and the door is in the "down" position (95% down), and "node 29" goes to +0 volts when the door is 95% UP and the contacts of switch SW_U are in mechanical contact ("closed"). The engineer must define the meanings of these voltages and all possible combinations (all 4 of them), including the "bad" ones (e.g. both nodes 22 and 29 at 0 volts, meaning that the door is open and closed at the same time). The circuit mindlessly responds to whatever voltages it experiences without any awareness of TRUTH or FALSEHOOD, RIGHT or WRONG, SAFE or DANGEROUS.
7774:, and the number terms also will be reduced in the process. Two abutting squares (2 x 1 horizontal or 1 x 2 vertical, even the edges represent abutting squares) lose one literal, four squares in a 4 x 1 rectangle (horizontal or vertical) or 2 x 2 square (even the four corners represent abutting squares) lose two literals, eight squares in a rectangle lose 3 literals, etc. (One seeks out the largest square or rectangles and ignores the smaller squares or rectangles contained totally within it. ) This process continues until all abutting squares are accounted for, at which point the propositional formula is minimized.
13307:
1373:
8820:
218:: "This pig has wings" AND "This pig is blue", whose internal structure is not considered. In contrast, in the predicate calculus, the first sentence breaks into "this pig" as the subject, and "has wings" as the predicate. Thus it asserts that object "this pig" is a member of the class (set, collection) of "winged things". The second sentence asserts that object "this pig" has an attribute "blue" and thus is a member of the class of "blue things". One might choose to write the two sentences connected with AND as:
5650:
9003:
144:(utterances, sentences, assertions) are considered to be either simple or compound. Compound propositions are considered to be linked by sentential connectives, some of the most common of which are "AND", "OR", "IF ... THEN ...", "NEITHER ... NOR ...", "... IS EQUIVALENT TO ..." . The linking semicolon ";", and connective "BUT" are considered to be expressions of "AND". A sequence of discrete sentences are considered to be linked by "AND"s, and formal analysis applies a
9024:
11553:
751:, engineers prefer to pull known objects from a small library—objects that have well-defined, predictable behaviors even in large combinations, (hence their name for the propositional calculus: "combinatorial logic"). The fewest behaviors of a single object are two (e.g. { OFF, ON }, { open, shut }, { UP, DOWN } etc.), and these are put in correspondence with { 0, 1 }. Such elements are called
8666:—that is, when an object m has a property P, but the object m is defined in terms of property P. The best advice for a rhetorician or one involved in deductive analysis is avoid impredicative definitions but at the same time be on the lookout for them because they can indeed create paradoxes. Engineers, on the other hand, put them to work in the form of propositional formulas with feedback.
276:
10624:"Boole's principal single innovation was law for logic: it stated that the mental acts of choosing the property x and choosing x again and again is the same as choosing x once... As consequence of it he formed the equations x•(1-x)=0 and x+(1-x)=1 which for him expressed respectively the law of contradiction and the law of excluded middle" (p. xxviiff). For Boole "1" was the
11541:, John Wiley & Sons, Inc., New York. No ISBN. Library of Congress Catalog Card Number: 68-21185. Tight presentation of engineering's analysis and synthesis methods, references McCluskey 1965. Unlike Suppes, Wickes' presentation of "Boolean algebra" starts with a set of postulates of a truth-table nature and then derives the customary theorems of them (p. 18ff).
4341:
over the other connectives. To "well-form" a formula, start with the connective with the highest rank and add parentheses around its components, then move down in rank (paying close attention to the connective's scope over which it is working). From most- to least-senior, with the predicate signs ∀x and ∃x, the IDENTITY = and arithmetic signs added for completeness:
11531:(no year cited) brought to Russell's and Whitehead's attention that what they considered their primitive propositions (connectives) could be reduced to a single |, nowadays known as the "stroke" or NAND (NOT-AND, NEITHER ... NOR...). Russell-Whitehead discuss this in their "Introduction to the Second Edition" and makes the definitions as discussed above.
3150:∨ n) are constructed from strings of two-argument AND and OR and written in abbreviated form without the parentheses. These, and other connectives as well, can then be used as building blocks for yet further connectives. Rhetoricians, philosophers, and mathematicians use truth tables and the various theorems to analyze and simplify their formulas.
10570:
one after another for the presence or absence of the assertion—then the law is considered intuitionistically appropriate. Thus an assertion such as: "This object must either BE or NOT BE (in the collection)", or "This object must either have this QUALITY or NOT have this QUALITY (relative to the objects in the collection)" is acceptable. See more at
10655:(PM). It is here that what we consider "modern" propositional logic first appeared. In particular, PM introduces NOT and OR and the assertion symbol ⊦ as primitives. In terms of these notions they define IMPLICATION → ( def. *1.01: ~p ∨ q ), then AND (def. *3.01: ~(~p ∨ ~q) ), then EQUIVALENCE p ←→ q (*4.01: (p → q) & ( q → p ) ).
10934:: For large "gains" k, e.g. k=100, 1/( 1 + e ) = 1/( 1 + e ) = { ≃0, ≃1 }. For example, if "The door is DOWN" means "The door is less than 50% of the way up", then a threshold thr=0.5 corresponding to 0.5*5.0 = +2.50 volts could be applied to a "linear" measuring-device with an output of 0 volts when fully closed and +5.0 volts when fully open.
984:. The symbols used will vary from author to author and between fields of endeavor. In general the abbreviations "T" and "F" stand for the evaluations TRUTH and FALSITY applied to the variables in the propositional formula (e.g. the assertion: "That cow is blue" will have the truth-value "T" for Truth or "F" for Falsity, as the case may be.).
7754:
6610:
2853:). the result of such a calculus will be another formula (i.e. a well-formed symbol string). Eventually, however, if one wants to use the calculus to study notions of validity and truth, one must add axioms that define the behavior of the symbols called "the truth values" {T, F} ( or {1, 0}, etc.) relative to the other symbols.
10569:
The use of the word "everything" in the law of excluded middle renders
Russell's expression of this law open to debate. If restricted to an expression about BEING or QUALITY with reference to a finite collection of objects (a finite "universe of discourse") -- the members of which can be investigated
9714:
The formula known as "clocked flip-flop" memory ("c" is the "clock" and "d" is the "data") is given below. It works as follows: When c = 0 the data d (either 0 or 1) cannot "get through" to affect output q. When c = 1 the data d "gets through" and output q "follows" d's value. When c goes from 1 to 0
5653:
The engineering symbol for the NAND connective (the 'stroke') can be used to build any propositional formula. The notion that truth (1) and falsity (0) can be defined in terms of this connective is shown in the sequence of NANDs on the left, and the derivations of the four evaluations of a NAND b are
4564:
The sign " = " (as distinguished from logical equivalence ≡, alternately ↔ or ⇔) symbolizes the assignment of value or meaning. Thus the string (a & ~(a)) symbolizes "0", i.e. it means the same thing as symbol "0" ". In some "systems" this will be an axiom (definition) perhaps shown as ( (a &
4324:
Enterprising readers might challenge themselves to invent an "axiomatic system" that uses the symbols { ∨, &, ~, (, ), variables a, b, c }, the formation rules specified above, and as few as possible of the laws listed below, and then derive as theorems the others as well as the truth-table
3954:
Example: The following truth table is De Morgan's law for the behavior of NOT over OR: ~(a ∨ b) ≡ (~a & ~b). To the left of the principal connective ≡ (yellow column labelled "taut") the formula ~(b ∨ a) evaluates to (1, 0, 0, 0) under the label "P". On the right of "taut" the formula
1738:
between them exhaustively and unambiguously. In the truth table below, d1 is the formula: ( (IF c THEN b) AND (IF NOT-c THEN a) ). Its fully reduced form d2 is the formula: ( (c AND b) OR (NOT-c AND a). The two formulas are equivalent as shown by the columns "=d1" and "=d2". Electrical engineers call
734:
seeing a blue cow—unless I am lying my statement is a TRUTH relative to the object of my (perhaps flawed) perception. But is the blue cow "really there"? What do you see when you look out the same window? In order to proceed with a verification, you will need a prior notion (a template) of both "cow"
8722:
In the abstract (ideal) case the simplest oscillating formula is a NOT fed back to itself: ~(~(p=q)) = q. Analysis of an abstract (ideal) propositional formula in a truth-table reveals an inconsistency for both p=1 and p=0 cases: When p=1, q=0, this cannot be because p=q; ditto for when p=0 and q=1.
7789:
Observe that by the
Idempotency law (A ∨ A) = A, we can create more terms. Then by association and distributive laws the variables to disappear can be paired, and then "disappeared" with the Law of contradiction (x & ~x)=0. The following uses brackets only to keep track of the terms; they
7777:
For example, squares #3 and #7 abut. These two abutting squares can lose one literal (e.g. "p" from squares #3 and #7), four squares in a rectangle or square lose two literals, eight squares in a rectangle lose 3 literals, etc. (One seeks out the largest square or rectangles.) This process continues
6665:
In the same way that a 2-row truth table displays the evaluation of a propositional formula for all 2 possible values of its variables, n variables produces a 2-square
Karnaugh map (even though we cannot draw it in its full-dimensional realization). For example, 3 variables produces 2 = 8 rows and 8
4912:
It can be shown that any expression matched by the grammar has a balanced number of left and right parentheses, and any nonempty initial segment of a formula has more left than right parentheses. This fact can be used to give an algorithm for parsing formulas. For example, suppose that an expression
4340:
In general, to avoid confusion during analysis and evaluation of propositional formulas, one can make liberal use of parentheses. However, quite often authors leave them out. To parse a complicated formula one first needs to know the seniority, or rank, that each of the connectives (excepting *) has
11203:
McCluskey comments that "it could be argued that the analysis is still incomplete because the word statement "The outputs are equal to the previous values of the inputs" has not been obtained"; he goes on to dismiss such worries because "English is not a formal language in a mathematical sense, it
11070:
cf Minsky 1967:75, section 4.2.3 "The method of parenthesis counting". Minsky presents a state machine that will do the job, and by use of induction (recursive definition) Minsky proves the "method" and presents a theorem as the result. A fully generalized "parenthesis grammar" requires an infinite
9239:
the output q=1 so when and if (s=0 & r=1) the flip-flop will be reset. Or, if (s=1 & r=0) the flip-flop will be set. In the abstract (ideal) instance in which s=1 ⇒ s=0 & r=1 ⇒ r=0 simultaneously, the formula q will be indeterminate (undecidable). Due to delays in "real" OR, AND and NOT
247:
are treated by the predicate calculus. Along with the new function symbolism "F(x)" two new symbols are introduced: ∀ (For all), and ∃ (There exists ..., At least one of ... exists, etc.). The predicate calculus, but not the propositional calculus, can establish the formal validity of the following
173:
must be about specific objects or specific states of mind. Each must have at least a subject (an immediate object of thought or observation), a verb (in the active voice and present tense preferred), and perhaps an adjective or adverb. "Dog!" probably implies "I see a dog" but should be rejected as
9057:
About the simplest memory results when the output of an OR feeds back to one of its inputs, in this case output "q" feeds back into "p". Given that the formula is first evaluated (initialized) with p=0 & q=0, it will "flip" once when "set" by s=1. Thereafter, output "q" will sustain "q" in the
9044:
at the input and q at the output. After "breaking" the feed-back, the truth table construction proceeds in the conventional manner. But afterwards, in every row the output q is compared to the now-independent input p and any inconsistencies between p and q are noted (i.e. p=0 together with q=1, or
6613:
A truth table will contain 2 rows, where n is the number of variables (e.g. three variables "p", "d", "c" produce 2 rows). Each row represents a minterm. Each minterm can be found on the Hasse diagram, on the Veitch diagram, and on the
Karnaugh map. (The evaluations of "p" shown in the truth table
5304:
in arguments, but arguments reduce to propositional formulas and can be evaluated the same as any other propositional formula. Here a valid inference means: "The formula that represents the inference evaluates to "truth" beneath its principal connective, no matter what truth-values are assigned to
9027:
A "clocked flip-flop" memory ("c" is the "clock" and "d" is the "data"). The data can change at any time when clock c=0; when clock c=1 the output q "tracks" the value of data d. When c goes from 1 to 0 it "traps" d = q's value and this continues to appear at q no matter what d does (as long as c
8836:
Analysis requires a delay to be inserted and then the loop cut between the delay and the input "p". The delay must be viewed as a kind of proposition that has "qd" (q-delayed) as output for "q" as input. This new proposition adds another column to the truth table. The inconsistency is now between
7761:
Use the values of the formula (e.g. "p") found by the truth-table method and place them in their into their respective (associated) Karnaugh squares (these are numbered per the Gray code convention). If values of "d" for "don't care" appear in the table, this adds flexibility during the reduction
328:
An algebra (and there are many different ones), loosely defined, is a method by which a collection of symbols called variables together with some other symbols such as parentheses (, ) and some sub-set of symbols such as *, +, ~, &, ∨, =, ≡, ∧, ¬ are manipulated within a system of
11111:
Wickes 1967:36ff. Wickes offers a good example of 8 of the 2 x 4 (3-variable maps) and 16 of the 4 x 4 (4-variable) maps. As an arbitrary 3-variable map could represent any one of 2=256 2x4 maps, and an arbitrary 4-variable map could represent any one of 2 = 65,536 different formula-evaluations,
1658:
and is the connective responsible for conditional goto's (jumps, branches). From this one connective all other connectives can be constructed (see more below). Although " IF c THEN b ELSE a " sounds like an implication it is, in its most reduced form, a switch that makes a decision and offers as
8678:
The simplest case occurs when an OR formula becomes one its own inputs e.g. p = q. Begin with (p ∨ s) = q, then let p = q. Observe that q's "definition" depends on itself "q" as well as on "s" and the OR connective; this definition of q is thus impredicative. Either of two conditions can
8674:
The notion of a propositional formula appearing as one of its own variables requires a formation rule that allows the assignment of the formula to a variable. In general there is no stipulation (either axiomatic or truth-table systems of objects and relations) that forbids this from happening.
3944:
The following "laws" of the propositional calculus are used to "reduce" complex formulas. The "laws" can be verified easily with truth tables. For each law, the principal (outermost) connective is associated with logical equivalence ≡ or identity =. A complete analysis of all 2 combinations of
3149:
As shown above, the CASE (IF c THEN b ELSE a ) connective is constructed either from the 2-argument connectives IF ... THEN ... and AND or from OR and AND and the 1-argument NOT. Connectives such as the n-argument AND (a & b & c & ... & n), OR (a ∨ b ∨ c ∨ ...
261:
Tarski asserts that the notion of IDENTITY (as distinguished from LOGICAL EQUIVALENCE) lies outside the propositional calculus; however, he notes that if a logic is to be of use for mathematics and the sciences it must contain a "theory" of IDENTITY. Some authors refer to "predicate logic with
8690:
of the inputs alone. That is, sometimes one looks at q and sees 0 and other times 1. To avoid this problem one has to know the state (condition) of the "hidden" variable p inside the box (i.e. the value of q fed back and assigned to p). When this is known the apparent inconsistency goes away.
766:
Thus an assignment of meaning of the variables and the two value-symbols { 0, 1 } comes from "outside" the formula that represents the behavior of the (usually) compound object. An example is a garage door with two "limit switches", one for UP labelled SW_U and one for DOWN labelled SW_D, and
9006:
About the simplest memory results when the output of an OR feeds back to one of its inputs, in this case output "q" feeding back into "p". The next simplest is the "flip-flop" shown below the once-flip. Analysis of these sorts of formulas can be done by either cutting the feedback path(s) or
3955:(~(b) ∨ ~(a)) also evaluates to (1, 0, 0, 0) under the label "Q". As the two columns have equivalent evaluations, the logical equivalence ≡ under "taut" evaluates to (1, 1, 1, 1), i.e. P ≡ Q. Thus either formula can be substituted for the other if it appears in a larger formula.
2833:
As noted above, Tarski considers IDENTITY to lie outside the propositional calculus, but he asserts that without the notion, "logic" is insufficient for mathematics and the deductive sciences. In fact the sign comes into the propositional calculus when a formula is to be evaluated.
10885:
Tarski p.54-68. Suppes calls IDENTITY a "further rule of inference" and has a brief development around it; Robbin, Bender and
Williamson, and Goodstein introduce the sign and its usage without comment or explanation. Hamilton p. 37 employs two signs ≠ and = with respect to the
4973:— the connective under which the overall evaluation of the formula occurs for the outer-most parentheses (which are often omitted). It also locates the inner-most connective where one would begin evaluatation of the formula without the use of a truth table, e.g. at "level 6".
3949:
distinct variables will result in a column of 1's (T's) underneath this connective. This finding makes each law, by definition, a tautology. And, for a given law, because its formula on the left and right are equivalent (or identical) they can be substituted for one another.
9234:
shown below the once-flip. Given that r=0 & s=0 and q=0 at the outset, it is "set" (s=1) in a manner similar to the once-flip. It however has a provision to "reset" q=0 when "r"=1. And additional complication occurs if both set=1 and reset=1. In this formula, the set=1
8698:. Propositional formulas with feedback lead, in their simplest form, to state machines; they also lead to memories in the form of Turing tapes and counter-machine counters. From combinations of these elements one can build any sort of bounded computational model (e.g.
5329:
Example 1: What does one make of the following difficult-to-follow assertion? Is it valid? "If it's sunny, but if the frog is croaking then it's not sunny, then it's the same as saying that the frog isn't croaking." Convert this to a propositional formula as follows:
344:
When the values are restricted to just two and applied to the notion of simple sentences (e.g. spoken utterances or written assertions) linked by propositional connectives this whole algebraic system of symbols and rules and evaluation-methods is usually called the
10957:
peculiar; in fact (a "+" b) = (a + (b - a*b)) where "+" is the "logical sum" but + and - are the true arithmetic counterparts. Occasionally all four notions do appear in a formula: A AND B = 1/2*( A plus B minus ( A XOR B ) ] (cf p. 146 in John
Wakerly 1978,
1380:
In general, the engineering connectives are just the same as the mathematics connectives excepting they tend to evaluate with "1" = "T" and "0" = "F". This is done for the purposes of analysis/minimization and synthesis of formulas by use of the notion of
6644:. A string of literals connected by ANDs is called a term. A string of literals connected by OR is called an alterm. Typically the literal ~(x) is abbreviated ~x. Sometimes the &-symbol is omitted altogether in the manner of algebraic multiplication.
329:
rules. These symbols, and well-formed strings of them, are said to represent objects, but in a specific algebraic system these objects do not have meanings. Thus work inside the algebra becomes an exercise in obeying certain laws (rules) of the algebra's
3172:
is following the convention of
Reichenbach. Some examples of convenient definitions drawn from the symbol set { ~, &, (, ) } and variables. Each definition is producing a logically equivalent formula that can be used for substitution or replacement.
2803:
equivalence sometimes appears in speech as in this example: " 'The sun is shining' means 'I'm biking' " Translated into a propositional formula the words become: "IF 'the sun is shining' THEN 'I'm biking', AND IF 'I'm biking' THEN 'the sun is shining'":
8642:
Then assign the variable "s" to the left-most sentence "This sentence is simple". Define "compound" c = "not simple" ~s, and assign c = ~s to "This sentence is compound"; assign "j" to "It is conjoined by AND". The second sentence can be expressed as:
6078:
In the following truth table the column labelled "taut" for tautology evaluates logical equivalence (symbolized here by ≡) between the two columns labelled d. Because all four rows under "taut" are 1's, the equivalence indeed represents a tautology.
6731:
When working with
Karnaugh maps one must always keep in mind that the top edge "wrap arounds" to the bottom edge, and the left edge wraps around to the right edge—the Karnaugh diagram is really a three- or four- or n-dimensional flattened object.
340:
For a well-formed sequence of symbols in the algebra —a formula— to have some usefulness outside the algebra the symbols are assigned meanings and eventually the variables are assigned values; then by a series of rules the formula is evaluated.
3153:
Electrical engineering uses drawn symbols and connect them with lines that stand for the mathematicals act of substitution and replacement. They then verify their drawings with truth tables and simplify the expressions as shown below by use of
8833:. If either of the delay and NOT are not abstract (i.e. not ideal), the type of analysis to be used will be dependent upon the exact nature of the objects that make up the oscillator; such things fall outside mathematics and into engineering.
2821:
Different authors use different signs for logical equivalence: ↔ (e.g. Suppes, Goodstein, Hamilton), ≡ (e.g. Robbin), ⇔ (e.g. Bender and
Williamson). Typically identity is written as the equals sign =. One exception to this rule is found in
3158:
or the theorems. In this way engineers have created a host of "combinatorial logic" (i.e. connectives without feedback) such as "decoders", "encoders", "mutifunction gates", "majority logic", "binary adders", "arithmetic logic units", etc.
691:
Evaluation of a propositional formula begins with assignment of a truth value to each variable. Because each variable represents a simple sentence, the truth values are being applied to the "truth" or "falsity" of these simple sentences.
156:
For example: The assertion: "This cow is blue. That horse is orange but this horse here is purple." is actually a compound proposition linked by "AND"s: ( ("This cow is blue" AND "that horse is orange") AND "this horse here is purple" )
1708:
Thus IF ... THEN ... ELSE—unlike implication—does not evaluate to an ambiguous "TRUTH" when the first proposition is false i.e. c = F in (c → b). For example, most people would reject the following compound proposition as a nonsensical
4332:, that is, they stand in place of an infinite number of instances. Thus ( x ∨ y ) ≡ ( y ∨ x ) might be used in one instance, ( p ∨ 0 ) ≡ ( 0 ∨ p ) and in another instance ( 1 ∨ q ) ≡ ( q ∨ 1 ), etc.
11347:. Emphasis on the notion of "algebra of classes" with set-theoretic symbols such as ∩, ∪, ' (NOT), ⊂ (IMPLIES). Later Goldstein replaces these with &, ∨, ¬, → (respectively) in his treatment of "Sentence Logic" pp. 76–93.
10943:
In actuality the digital 1 and 0 are defined over non-overlapping ranges e.g. { "1" = +5/+0.2/−1.0 volts, 0 = +0.5/−0.2 volts }. When a value falls outside the defined range(s) the value becomes "u" -- unknown; e.g. +2.3 would be
11226:
The notion of delay and the principle of local causation as caused ultimately by the speed of light appears in Robin Gandy (1980), "Church's thesis and
Principles for Mechanisms", in J. Barwise, H. J. Keisler and K. Kunen, eds.,
11129:
and Kleene believed that the classical paradoxes are uniformly examples of this sort of definition. But Kleene went on to assert that the problem has not been solved satisfactorily and impredicative definitions can be found in
1721:
Example: The proposition " IF 'Winston Churchill was Chinese' THEN 'The sun rises in the east' " evaluates as a TRUTH given that 'Winston Churchill was Chinese' is a FALSEHOOD and 'The sun rises in the east' evaluates as a
11231:, North-Holland Publishing Company (1980) 123-148. Gandy considered this to be the most important of his principles: "Contemporary physics rejects the possibility of instantaneous action at a distance" (p. 135). Gandy was
4450:
d & c ∨ p & ~(c & ~d) ≡ c & d ∨ p & c ∨ p & ~d rewritten is ( ( (d & c) ∨ ( p & ~((c & ~(d)) ) ) ) ≡ ( (c & d) ∨ (p & c) ∨ (p & ~(d)) )
6618:
Reduction to normal form is relatively simple once a truth table for the formula is prepared. But further attempts to minimize the number of literals (see below) requires some tools: reduction by De Morgan's laws and
4494:( (c & d) ∨ (p & c) ∨ (p & ~d) ) above should be written ( ((c & d) ∨ (p & c)) ∨ (p & ~(d) ) ) or possibly ( (c & d) ∨ ( (p & c) ∨ (p & ~(d)) ) )
11031:
Hamilton p. 37. Bender and Williamson p. 29 state "In what follows, we'll replace "equals" with the symbol " ⇔ " (equivalence) which is usually used in logic. We use the more familiar " = " for assigning meaning and
1733:
The use of the IF ... THEN ... ELSE construction avoids controversy because it offers a completely deterministic choice between two stated alternatives; it offers two "objects" (the two alternatives b and a), and it
5658:
A set of logical connectives is called complete if every propositional formula is tautologically equivalent to a formula with just the connectives in that set. There are many complete sets of connectives, including
9032:
Without delay, inconsistencies must be eliminated from a truth table analysis. With the notion of "delay", this condition presents itself as a momentary inconsistency between the fed-back output variable q and p =
3237:
but shown (for illustrative purposes) with specific letters a, b, c for the variables, whereas any variable letters can go in their places as long as the letter substitutions follow the rule of substitution below.
3167:
A definition creates a new symbol and its behavior, often for the purposes of abbreviation. Once the definition is presented, either form of the equivalent symbol or formula can be used. The following symbolism
724:, meanings (pattern-matching templates) must first be applied to the words, and then these meaning-templates must be matched against whatever it is that is being asserted. For example, my utterance "That cow is
6627:
are very suitable a small number of variables (5 or less). Some sophisticated tabular methods exist for more complex circuits with multiple outputs but these are beyond the scope of this article; for more see
6918:
by converting the circles to abutting squares, and Karnaugh simplified the Veitch diagram by converting the minterms, written in their literal-form (e.g. ~abc~d) into numbers. The method proceeds as follows:
231:"winged things", p is either found to be a member of this domain or not. Thus there is a relationship W (wingedness) between p (pig) and { T, F }, W(p) evaluates to { T, F } where { T, F } is the set of the
6680:
In the following table, observe the peculiar numbering of the rows: (0, 1, 3, 2, 6, 7, 5, 4, 0). The first column is the decimal equivalent of the binary equivalent of the digits "cba", in other words:
1376:
Engineering symbols have varied over the years, but these are commonplace. Sometimes they appear simply as boxes with symbols in them. "a" and "b" are called "the inputs" and "c" is called "the output".
11022:
The use of quote marks around the expressions is not accidental. Tarski comments on the use of quotes in his "18. Identity of things and identity of their designations; use of quotation marks" p. 58ff.
11244:
McKlusky p. 194-5 discusses "breaking the loop" and inserts "amplifiers" to do this; Wickes (p. 118-121) discuss inserting delays. McCluskey p. 195ff discusses the problem of "races" caused by delays.
3423:
4770:
A key property of formulas is that they can be uniquely parsed to determine the structure of the formula in terms of its propositional variables and logical connectives. When formulas are written in
235:"true" and "false". Likewise for B (blueness) and p (pig) and { T, F }: B(p) evaluates to { T, F }. So one now can analyze the connected assertions "B(p) AND W(p)" for its overall truth-value, i.e.:
4328:
If used in an axiomatic system, the symbols 1 and 0 (or T and F) are considered to be well-formed formulas and thus obey all the same rules as the variables. Thus the laws listed below are actually
227:
The generalization of "this pig" to a (potential) member of two classes "winged things" and "blue things" means that it has a truth-relationship with both of these classes. In other words, given a
10979:
A careful look at its Karnaugh map shows that IF...THEN...ELSE can also be expressed, in a rather round-about way, in terms of two exclusive-ORs: ( (b AND (c XOR a)) OR (a AND (c XOR b)) ) = d.
3616:
865:
3915:
6936:
has been reduced to its (unminimized) conjunctive normal form: each row has its minterm expression and these can be OR'd to produce the formula in its (unminimized) conjunctive normal form.
11217:
More precisely, given enough "loop gain", either oscillation or memory will occur (cf McCluskey p. 191-2). In abstract (idealized) mathematical systems adequate loop gain is not a problem.
3790:
3137:
or laws of identity and nullity. The choice of which ones to use, together with laws such as commutation and distribution, is up to the system's designer as long as the set of axioms is
10822:
Rosenbloom discusses this problem of implication at some length. Most philosophers and mathematicians just accept the material definition as given above. But some do not, including the
3704:
352:
While some of the familiar rules of arithmetic algebra continue to hold in the algebra of propositions (e.g. the commutative and associative laws for AND and OR), some do not (e.g. the
5960:
5347:? In other words, when evaluated will this yield a tautology (all T) beneath the logical-equivalence symbol ≡ ? The answer is NO, it is not valid. However, if reconstructed as an
3518:
3853:
5919:
3884:
11194:
and this makes its definition impredicative. Kleene asserts that attempts to argue this away can be used to uphold the impredicative definitions in the paradoxes.(Kleene 1952:43).
937:
210:(stringing together) of symbols) into a form with the following blank-subject structure " ___|predicate", and the predicate in turn generalized to all things with that property.
182:
For the purposes of the propositional calculus a compound proposition can usually be reworded into a series of simple sentences, although the result will probably sound stilted.
7781:
Example: The map method usually is done by inspection. The following example expands the algebraic method to show the "trick" behind the combining of terms on a Karnaugh map:
5689:
3032:
the value F (or a meaning of "F") to the entire expression. The definitions also serve as formation rules that allow substitution of a value previously derived into a formula:
2799:" is not the same thing as "identity". For example, most would agree that the assertion "That cow is blue" is identical to the assertion "That cow is blue". On the other hand,
759:. Whenever decisions must be made in an analog system, quite often an engineer will convert an analog behavior (the door is 45.32146% UP) to digital (e.g. DOWN=0 ) by use of a
206:(a verb or possibly verb-clause that asserts a quality or attribute of the object(s)). The predicate calculus then generalizes the "subject|predicate" form (where | symbolizes
5785:
5721:
969:
5753:
3462:
747:
Engineers try to avoid notions of truth and falsity that bedevil philosophers, but in the final analysis engineers must trust their measuring instruments. In their quest for
11505:(pbk.) Translation/reprints of Frege (1879), Russell's letter to Frege (1902) and Frege's letter to Russell (1902), Richard's paradox (1905), Post (1921) can be found here.
10930:
modelling offers a good mathematical model for a comparator as follows: Given a signal S and a threshold "thr", subtract "thr" from S and substitute this difference d to a
3323:( connected by ≡ or ↔) to the formula that replaces it, and (ii) unlike substitution its permissible for the replacement to occur only in one place (i.e. for one formula).
824:
3822:
9045:
p=1 and q=0); when the "line" is "remade" both are rendered impossible by the Law of contradiction ~(p & ~p)). Rows revealing inconsistencies are either considered
6720:
where each corner's variables change only one at a time as one moves around the edges of the cube. Hasse diagrams (hypercubes) flattened into two dimensions are either
3733:
3644:, left and right parentheses, and all the logical connectives under consideration. Each logical connective corresponds to a formula building operation, a function from
10890:
of a formula in a formal calculus. Kleene p. 70 and Hamilton p. 52 place it in the predicate calculus, in particular with regards to the arithmetic of natural numbers.
4938:
3538:
3482:
885:
801:
3558:
905:
10635:'s massive undertaking (1879) resulted in a formal calculus of propositions, but his symbolism is so daunting that it had little influence excepting on one person:
6673:
Any propositional formula can be reduced to the "logical sum" (OR) of the active (i.e. "1"- or "T"-valued) minterms. When in this form the formula is said to be in
6008:
5988:
5862:
5842:
3578:
6034:
Example: The following shows how a theorem-based proof of "(c, b, 1) ≡ (c → b)" would proceed, below the proof is its truth-table verification. ( Note: (c → b) is
2991:) define the equivalent of the truth tables for the ~ (NOT) and → (IMPLICATION) connectives of his system. The first one derives F ≠ T and T ≠ F, in other words "
3279:: The variable or sub-formula to be substituted with another variable, constant, or sub-formula must be replaced in all instances throughout the overall formula.
286:
11414:, Prentice-Hall, Inc, Englewood Cliffs, N.J.. No ISBN. Library of Congress Catalog Card Number 67-12342. Useful especially for computability, plus good sources.
10911:"held that every idea must either originate directly in sense experience or else be compounded of ideas thus originating"; quoted from Quine reprinted in 1996
4774:, as above, unique readability is ensured through an appropriate use of parentheses in the definition of formulas. Alternatively, formulas can be written in
9007:
inserting (ideal) delay in the path. A cut path and an assumption that no delay occurs anywhere in the "circuit" results in inconsistencies for some of the
6927:
Produce the formula's truth table. Number its rows using the binary-equivalents of the variables (usually just sequentially 0 through n-1) for n variables.
5803:(1927:xvii). Since it is complete on its own, all other connectives can be expressed using only the stroke. For example, where the symbol " ≡ " represents
11686:
6589:
An arbitrary propositional formula may have a very complicated structure. It is often convenient to work with formulas that have simpler forms, known as
5755:. There are two binary connectives that are complete on their own, corresponding to NAND and NOR, respectively. Some pairs are not complete, for example
4416:
Thus the formula can be parsed—but because NOT does not obey the distributive law, the parentheses around the inner formula (~c & ~d) is mandatory:
8651:
If truth values are to be placed on the sentences c = ~s and j, then all are clearly FALSEHOODS: e.g. "This sentence is complex" is a FALSEHOOD (it is
2808:"IF 's' THEN 'b' AND IF 'b' THEN 's' " is written as ((s → b) & (b → s)) or in an abbreviated form as (s ↔ b). As the rightmost symbol string is a
6654:
p, q, r, s are variables. (((p ∨ ~(q) ) ∨ r) ∨ ~(s) ) is an alterm. This can be abbreviated as (p ∨ ~q ∨ r ∨ ~s).
10672:(1921) develops the truth-table method of analysis in his "Introduction to a general theory of elementary propositions". He notes Nicod's stroke | .
11418:
6651:
a, b, c, d are variables. ((( a & ~(b) ) & ~(c)) & d) is a term. This can be abbreviated as (a & ~b & ~c & d), or a~b~cd.
12361:
10605:'s work (1827) resulted in the notion of "quantification of the predicate" (1827) (nowadays symbolized as ∀ ≡ "for all"). A "row" instigated by
297:
9011:(combination of inputs and outputs, e.g. (p=0, s=1, r=1) results in an inconsistency). When delay is present these inconsistencies are merely
987:
The connectives go by a number of different word-usages, e.g. "a IMPLIES b" is also said "IF a THEN b". Some of these are shown in the table.
11402:
and developed some notable theorems with Quine and on his own. For those interested in the history, the book contains a wealth of references.
8829:: If a delay (ideal or non-ideal) is inserted in the abstract formula between p and q then p will oscillate between 1 and 0: 101010...101...
6677:. But even though it is in this form, it is not necessarily minimized with respect to either the number of terms or the number of literals.
12444:
11585:
7785:
Minterms #3 and #7 abut, #7 and #6 abut, and #4 and #6 abut (because the table's edges wrap around). So each of these pairs can be reduced.
5376:( ((a) → (b)) & (b) → (a) ) is well formed, but an invalid argument as shown by the red evaluation under the principal implication:
2849:, ... } and formula-formation rules (rules about how to make more symbol strings from previous strings by use of e.g. substitution and
2837:
In some systems there are no truth tables, but rather just formal axioms (e.g. strings of symbols from a set { ~, →, (, ), variables p
392:
they have designed using synthesis techniques and then apply various reduction and minimization techniques to simplify their designs.
10581:
applied to propositions had to wait until the early 19th century. In an (adverse) reaction to the 2000 year tradition of Aristotle's
10675:
Whitehead and Russell add an introduction to their 1927 re-publication of PM adding, in part, a favorable treatment of the "stroke".
4490:: The connectives are considered to be unary (one-variable, e.g. NOT) and binary (i.e. two-variable AND, OR, IMPLIES). For example:
11089:
cf Reichenbach p. 68 for a more involved discussion: "If the inference is valid and the premises are true, the inference is called
11049:
and is not a formal symbol with the following meaning: "by symbol ' s ' is to have the same meaning as the formula '(c & d)' ".
8686:. Without knowledge of what is going on "inside" the formula-"box" from the outside it would appear that the output is no longer a
951:
The "theory-extension" connective EQUALS (alternately, IDENTITY, or the sign " = " as distinguished from the "logical connective"
12758:
4508:
would appear. When the NOT is over a formula with more than one symbol, then the parentheses are mandatory, e.g. ~(a ∨ b).
4325:
valuations for ∨, &, and ~. One set attributed to Huntington (1904) (Suppes:204) uses eight of the laws defined below.
11557:
3384:
6708:
This numbering comes about because as one moves down the table from row to row only one variable at a time changes its value.
4516:
OR distributes over AND and AND distributes over OR. NOT does not distribute over AND or OR. See below about De Morgan's law:
3283:
Example: (c & d) ∨ (p & ~(c & ~d)), but (q1 & ~q2) ≡ d. Now wherever variable "d" occurs, substitute (q
12916:
11364:
10643:
he studied Frege's work and suggested a (famous and notorious) emendation with respect to it (1904) around the problem of an
6957:
However, this formula be reduced both in the number of terms (from 4 to 3) and in the total count of its literals (12 to 6).
403:
should behave given the addition of variables "b" and "a" and "carry_in" "ci", and the results "carry_out" "co" and "sum" Σ:
11704:
11398:, McGraw-Hill Book Company, New York. No ISBN. Library of Congress Catalog Card Number 65-17394. McCluskey was a student of
9715:
the last value of the data remains "trapped" at output "q". As long as c=0, d can change value without causing q to change.
12771:
12094:
178:
Example: "That purple dog is running", "This cow is blue", "Switch M31 is closed", "This cap is off", "Tomorrow is Friday".
395:
Synthesis: Engineers in particular synthesize propositional formulas (that eventually end up as circuits of symbols) from
11523:, Cambridge University Press, no ISBN. In the years between the first edition of 1912 and the 2nd edition of 1927, H. M.
9746:
The state diagram is similar in shape to the flip-flop's state diagram, but with different labelling on the transitions.
8655:, by definition). So their conjunction (AND) is a falsehood. But when taken in its assembled form, the sentence a TRUTH.
5335:" IF (a AND (IF b THEN NOT-a) THEN NOT-a" where " a " represents "its sunny" and " b " represents "the frog is croaking":
6614:
are not shown in the Hasse, Veitch and Karnaugh diagrams; these are shown in the Karnaugh map of the following section.)
3583:
1739:
the fully reduced formula the AND-OR-SELECT operator. The CASE (or SWITCH) operator is an extension of the same idea to
832:
12776:
12766:
12503:
12356:
11709:
3889:
675:, etc. A propositional variable is intended to represent an atomic proposition (assertion), such as "It is Saturday" =
11700:
12912:
11502:
11482:
11451:
11431:
11382:
11344:
11327:
11307:
11270:
10967:
10606:
315:
12254:
7804:
q = ( (~p & d & c ) ∨ (p & d & c) ∨ (p & d & ~c) ∨ (p & ~d & ~c) )
6949:( (~p & d & c ) ∨ (p & d & c) ∨ (p & d & ~c) ∨ (p & ~d & ~c) ) = q
3016:) specifies the third row in the truth table, and the other three rows then come from an application of definition (
13009:
12753:
11578:
7757:
Steps in the reduction using a Karnaugh map. The final result is the OR (logical "sum") of the three reduced terms.
5373:"If pigs have wings, some winged animals are good to eat. Some winged animals are good to eat, so pigs have wings."
6065:
Commutivity and Identity (( 1 & ~c) = (~c & 1) = ~c, and (( 1 & b) ≡ (b & 1) ≡ b: ( ~c ∨ b )
3749:
13331:
12314:
12007:
10867:(PM) p. 91 eschews "the" because they require a clear-cut "object of sensation"; they stipulate the use of "this"
4532:
NOT, when distributed over OR or AND, does something peculiar (again, these can be verified with a truth-table):
11748:
10617:
to write up his ideas on logic, and to publish them as MAL in 1847" (Grattin-Guinness and Bornet 1997:xxviii).
7778:
until all abutting squares are accounted for, at which point the propositional formula is said to be minimized.
4952:
is a formula, there is exactly one symbol left after this expression, this symbol is a closing parenthesis, and
3669:
161:
Simple propositions are declarative in nature, that is, they make assertions about the condition or nature of a
13270:
12972:
12735:
12730:
12555:
11976:
11660:
10953:
While the notion of logical product is not so peculiar (e.g. 0*0=0, 0*1=0, 1*0=0, 1*1=1), the notion of (1+1=1
5925:
775:
Arbitrary propositional formulas are built from propositional variables and other propositional formulas using
368:, philosophers, rhetoricians and mathematicians reduce arguments to formulas and then study them (usually with
4498:
However, a truth-table demonstration shows that the form without the extra parentheses is perfectly adequate.
3489:
13265:
13048:
12965:
12678:
12609:
12486:
11728:
10651:). Russell's work led to a collaboration with Whitehead that, in the year 1912, produced the first volume of
6629:
4548:
Absorption, in particular the first one, causes the "laws" of logic to differ from the "laws" of arithmetic:
4440:
check 9 ( -parenthesis and 9 ) -parenthesis: ( ( ( (a) & (a → b) ) ) ≡ ( ( (a) & (~(a) ∨ b) ) )
679:(here the symbol = means " ... is assigned the variable named ...") or "I only go to the movies on Monday" =
3827:
13356:
13190:
13016:
12702:
12336:
11935:
10916:
7771:
6641:
5870:
4505:
3858:
132:" is not a value, but denotes a value. In some contexts, maintaining the distinction may be of importance.
28:
5799:, and written with a vertical bar | or vertical arrow ↑. The completeness of this connective was noted in
13068:
13063:
12673:
12412:
12341:
11670:
11571:
10666:
demonstrate that only one connective, the "stroke" | is sufficient to express all propositional formulas.
7770:
Minterms of adjacent (abutting) 1-squares (T-squares) can be reduced with respect to the number of their
5654:
shown along the bottom. The more common method is to use the definition of the NAND from the truth table.
1726:
In recognition of this problem, the sign → of formal implication in the propositional calculus is called
910:
407:
Example: in row 5, ( (b+a) + ci ) = ( (1+0) + 1 ) = the number "2". written as a binary number this is 10
384:, before we can conclude that a robot is an artificial intelligence the robot must pass the Turing test."
10805:
E. J. McCluskey and H. Shorr develop a method for simplifying propositional (switching) circuits (1962).
12997:
12587:
11981:
11949:
11640:
11458:
10686:
5662:
4504:: While ~(a) where a is a single variable is perfectly clear, ~a is adequate and is the usual way this
2827:
5758:
5694:
954:
13287:
13236:
13133:
12631:
12592:
12069:
11714:
11102:
As well as the first three, Hamilton pp.19-22 discusses logics built from only | (NAND), and ↓ (NOR).
5726:
3438:
2812:
for a new symbol in terms of the symbols on the left, the use of the IDENTITY sign = is appropriate:
980:
The following are the connectives common to rhetoric, philosophy and mathematics together with their
243:
In particular, simple sentences that employ notions of "all", "some", "a few", "one of", etc. called
115:
11743:
13336:
13128:
13058:
12597:
12449:
12432:
12155:
11635:
8663:
4957:
1670:
The following three propositions are equivalent (as indicated by the logical equivalence sign ≡ ):
1664:
806:
739:", and an ability to match the templates against the object of sensation (if indeed there is one).
8694:
To understand the behavior of formulas with feedback requires the more sophisticated analysis of
290:
that states a Knowledge editor's personal feelings or presents an original argument about a topic.
13346:
12960:
12937:
12898:
12784:
12725:
12371:
12291:
12135:
12079:
11692:
10775:
builds a multiplier using relays (1937–1938). He has to hand-wind his own relay coils to do this.
10543:
9231:
6674:
6598:
6594:
6014:(c, b, a) = d represents ( (c → b) ∨ (~c → a) ) ≡ ( (c & b) ∨ (~c & a) ) = d
4779:
377:
6670:. Each Karnaugh-map square and its corresponding truth-table evaluation represents one minterm.
3795:
13250:
12977:
12955:
12922:
12815:
12661:
12646:
12619:
12570:
12454:
12389:
12214:
12180:
12175:
12049:
11880:
11857:
11509:
10640:
10547:
8687:
7742:= (~p&d&c) ∨ (~p&d&c) ∨ (p&d&~c ) ∨ (p&d&c )
6933:
6011:
4743:
3709:
2878:
2795:
The first table of this section stars *** the entry logical equivalence to note the fact that "
1402:
651:
346:
293:
59:
4434:& has seniority both sides: ( ( ( (a) & (a → b) ) ) ≡ ( ( (a) & (~a ∨ b) ) )
198:
of propositions" It breaks a simple sentence down into two parts (i) its subject (the object (
35:. If the values of all variables in a propositional formula are given, it determines a unique
13351:
13180:
13033:
12825:
12543:
12279:
12185:
12044:
12029:
11910:
11351:
10864:
10699:(1937) invents the binary adder using mechanical relays. He builds this on his kitchen table.
10625:
8634:
Given the following examples-as-definitions, what does one make of the subsequent reasoning:
4920:
3626:
3523:
3467:
870:
786:
721:
6941:
Example: ((c & d) ∨ (p & ~(c & (~d)))) = q in conjunctive normal form is:
3543:
890:
13153:
13115:
12992:
12796:
12636:
12560:
12538:
12366:
12324:
12223:
12190:
12054:
11842:
11753:
10648:
6666:
Karnaugh squares; 4 variables produces 16 truth-table rows and 16 squares and therefore 16
5993:
5973:
5847:
5827:
4749:
4520:
Distributive law for OR: ( c ∨ ( a & b) ) ≡ ( (c ∨ a) & (c ∨ b) )
3563:
3426:
3134:
1727:
8638:(1) "This sentence is simple." (2) "This sentence is complex, and it is conjoined by AND."
6601:. Any propositional formula can be reduced to its conjunctive or disjunctive normal form.
6062:
Distribute "(1) &" over ((~c) ∨ b): ( ((1) & (~c)) ∨ ((1) & b )) )
4523:
Distributive law for AND: ( c & ( a ∨ b) ) ≡ ( (c & a) ∨ (c & b) )
8:
13341:
13282:
13173:
13158:
13138:
13095:
12982:
12932:
12858:
12803:
12740:
12533:
12528:
12476:
12244:
12233:
11905:
11805:
11733:
11724:
11720:
11655:
11650:
11489:
11280:
4785:
The inductive definition of infix formulas in the previous section can be converted to a
3141:(i.e. sufficient to form and to evaluate any well-formed formula created in the system).
3133:
specify these valuation axioms at the outset in the form of certain formulas such as the
2882:
from the wffs of his system L to the range (output) { T, F }, given that each variable p
2861:
2796:
1743:
possible, but mutually exclusive outcomes. Electrical engineers call the CASE operator a
1650:
The IF ... THEN ... ELSE ... connective appears as the simplest form of CASE operator of
1156:
717:
365:
228:
203:
55:
32:
20:
10601:
had critically analyzed the syllogistic logic with a sympathy toward Locke's semiotics.
13311:
13080:
13043:
13028:
13021:
13004:
12808:
12790:
12656:
12582:
12565:
12518:
12331:
12240:
12074:
12059:
12019:
11971:
11956:
11944:
11900:
11875:
11645:
11594:
11258:
10610:
8711:
8695:
7862:
Distributive law ( x & (y ∨ z) ) = ( (x & y) ∨ (x & z) ) :
6712:
is derived from this notion. This notion can be extended to three and four-dimensional
3246:(a → b), other variable-symbols such as "SW2" and "CON1" might be used, i.e. formally:
1655:
776:
716:—derived from experience and thereby susceptible to confirmation by third parties (the
244:
191:
12264:
1372:
13306:
13246:
13053:
12863:
12853:
12745:
12626:
12461:
12437:
12218:
12202:
12107:
12084:
11961:
11930:
11895:
11790:
11625:
11498:
11478:
11447:
11427:
11378:
11360:
11340:
11323:
11303:
11266:
11135:
11013:-- is required by the definition that Kleene gives the CASE operator (Kleene 1952229)
10963:
9002:
8819:
6640:
In electrical engineering, a variable x or its negation ~(x) can be referred to as a
5365:
Other circumstances may be preventing the frog from croaking: perhaps a crane ate it.
3225:
The definitions above for OR, IMPLICATION, XOR, and logical equivalence are actually
1696:( (c & b) ∨ (~c & a) ) ≡ " ( 'Counter is zero' AND 'go to instruction
748:
709:
252:"All blue pigs have wings but some pigs have no wings, hence some pigs are not blue".
232:
170:
107:
9058:"flipped" condition (state q=1). This behavior, now time-dependent, is shown by the
948:
Constant 0-ary connectives ⊤ and ⊥ (alternately, constants { T, F }, { 1, 0 } etc. )
13260:
13255:
13148:
13105:
12927:
12888:
12883:
12868:
12694:
12651:
12548:
12346:
12296:
11870:
11832:
11515:
11406:
11314:
10931:
10789:
10785:
10659:
10636:
10531:
8707:
4790:
3378:
1660:
1651:
353:
71:
5325:
valid is to submit it to verification with a truth table or by use of the "laws":
5305:
its variables", i.e. the formula is a tautology. Quite possibly a formula will be
4480:
Associative law for OR: (( a ∨ b ) ∨ c ) ≡ ( a ∨ (b ∨ c) )
3622:
This inductive definition can be easily extended to cover additional connectives.
165:
object of sensation e.g. "This cow is blue", "There's a coyote!" ("That coyote IS
13241:
13231:
13185:
13168:
13123:
13085:
12987:
12907:
12714:
12641:
12614:
12602:
12508:
12422:
12396:
12351:
12319:
12120:
11922:
11865:
11815:
11780:
11738:
10799:
10795:
10598:
10539:
9046:
8703:
4775:
4467:
4463:
4437:~ has seniority: ( ( ( (a) & (a → b) ) ) ≡ ( ( (a) & (~(a) ∨ b) ) )
720:
of meaning). Empiricits hold that, in general, to arrive at the truth-value of a
400:
6059:
Law of excluded middle (((~c) ∨ c ) = 1 ): ( (1) & ((~c) ∨ b ) )
13226:
13205:
13163:
13143:
13038:
12893:
12491:
12481:
12471:
12466:
12400:
12274:
12150:
12039:
12034:
12012:
11613:
11438:
11122:
10696:
10602:
8699:
7898:
Law of identity ( x ∨ 0 ) = x leading to the reduced form of the formula:
7753:
6721:
6609:
6056:
Distribute "~c V" over (c & b): ( ((~c) ∨ c ) & ((~c) ∨ b )
5796:
4786:
4771:
2856:
For example, Hamilton uses two symbols = and ≠ when he defines the notion of a
1689:' ) AND ( IF 'It is NOT the case that counter is zero' THEN 'go to instruction
1685:( (c → b) & (~c → a) ) ≡ ( ( IF 'counter is zero' THEN 'go to instruction
656:
389:
11310:. This text is used in a "lower division two-quarter course" at UC San Diego.
10577:
Although a propositional calculus originated with Aristotle, the notion of an
5649:
148:"parenthesis rule" with respect to sequences of simple propositions (see more
13325:
13200:
12878:
12385:
12170:
12160:
12130:
12115:
11785:
11469:
11399:
10781:
10632:
9059:
9016:
6717:
3130:
756:
372:) for correctness (soundness). For example: Is the following argument sound?
207:
199:
119:
11126:
10802:(1956) address the theory of sequential (i.e. switching-circuit) "machines".
4423:
Example: " a & a → b ≡ a & ~a ∨ b " rewritten (rigorously) is
337:(meaning) of the symbols. The meanings are to be found outside the algebra.
185:
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12947:
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10690:
10614:
10571:
6915:
6725:
6624:
5295:
4483:
Associative law for AND: (( a & b ) & c ) ≡ ( a & (b & c) )
4329:
3359:
Use the notion of "schema" to substitute b for a in 2: ( (a & ~a) ≡ 0 )
3226:
3155:
2850:
1386:
752:
194:
goes a step further than the propositional calculus to an "analysis of the
106:", but, more precisely, a propositional formula is not a proposition but a
9023:
9015:
and expire when the delay(s) expire. The drawings on the right are called
7794:
Put the formula in conjunctive normal form with the formula to be reduced:
13210:
13090:
12269:
12259:
12206:
11890:
11810:
11795:
11675:
11620:
11232:
10772:
7880:
Commutative law and law of contradiction (x & ~x) = (~x & x) = 0:
6620:
1744:
1700:) OR ( 'It is NOT the case that 'counter is zero' AND 'go to instruction
981:
396:
381:
369:
265:
99:
36:
9040:
A truth table reveals the rows where inconsistencies occur between p = q
6909:
4559:
12140:
11995:
11966:
11772:
10927:
10917:
http://www.marxists.org/reference/subject/philosophy/works/us/quine.htm
10908:
10904:
10663:
10586:
7833:
Associative law (x ∨ (y ∨ z)) = ( (x ∨ y) ∨ z )
4420:
Example: " d & c ∨ w " rewritten is ( (d & c) ∨ w )
760:
701:
975:
13292:
13195:
12248:
12165:
12125:
12089:
12025:
11837:
11827:
11800:
11563:
11390:
10669:
10594:
10582:
10554:
Example: Here O is an expression about an object's BEING or QUALITY:
10535:
8683:
6713:
6709:
5358:"Saying it's sunny, but if the frog is croaking then it's not sunny,
5301:
4940:. Starting after the second symbol, match the shortest subexpression
3425:. The set of formulas over a given set of propositional variables is
3365:(see below for how to distribute "a ∨" over (b & ~b), etc.)
334:
145:
11041:
Reichenbach p. 20-22 and follows the conventions of PM. The symbol =
9240:
the result will be unknown at the outset but thereafter predicable.
5309:
but not valid. Another way of saying this is: "Being well-formed is
3640:
denote the set of all strings from an alphabet including symbols in
13277:
13075:
12523:
12228:
11822:
11495:
From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931
11131:
10826:; they consider it a form of the law of excluded middle misapplied.
10792:(1953) develop map-methods for simplifying propositional functions.
10644:
6667:
4569:
0 ); in other systems, it may be derived in the truth table below:
4431:→ has seniority: ( ( a & (a → b) ) ≡ ( a & ~a ∨ b ) )
11475:
Introduction to Logic and to the Methodology of Deductive Sciences
8669:
3319:: (i) the formula to be replaced must be within a tautology, i.e.
262:
identity" to emphasize this extension. See more about this below.
102:, a propositional formula is often more briefly referred to as a "
12873:
11665:
11524:
11457:
On his page 204 in a footnote he references his set of axioms to
10991:
10903:(built-in, born-with) knowledge. "Radical reductionists" such as
8659:
6044:
Begin with the reduced form: ( (c & b) ∨ (~c & a) )
4428:≡ has seniority: ( ( a & a → b ) ≡ ( a & ~a ∨ b ) )
6010:} ) forms a complete set. In the following the IF...THEN...ELSE
3362:
Use 2 to replace 0 with (b & ~b): ( a ∨ (b & ~b) )
1659:
outcome only one of two alternatives "a" or "b" (hence the name
214:
Example: "This blue pig has wings" becomes two sentences in the
11552:
10778:
Textbooks about "switching circuits" appear in the early 1950s.
700:
The truth values are only two: { TRUTH "T", FALSITY "F" }. An
686:
330:
11357:
George Boole: Selected Manuscripts on Logic and its Philosophy
10960:
Error Detecting Codes, Self-Checking Circuits and Applications
2826:. For more about the philosophy of the notion of IDENTITY see
12417:
11763:
11608:
11528:
11461:, "Sets of Independent Postulates for the Algebra of Logic",
7908:
q = ( (d & c) ∨ (p & d) ∨ (p & ~c) )
4742:
Complement for OR: (a ∨ ~a) = 1 or (a ∨ ~a) = T,
3625:
The inductive definition can also be rephrased in terms of a
1394:
659:), symbolic expressions are often denoted by variables named
10620:
About his contribution Grattin-Guinness and Bornet comment:
1730:
to distinguish it from the everyday, intuitive implication.
1645:
9049:
or just eliminated as inconsistent and hence "impossible".
8837:"qd" and "p" as shown in red; two stable states resulting:
5970:
This connective together with { 0, 1 }, ( or { F, T } or {
730:!" Is this statement a TRUTH? Truly I said it. And maybe I
287:
personal reflection, personal essay, or argumentative essay
11154:
and the two parts into which the number line is cut, i.e.
10693:(1919) describe a "trigger relay" made from a vacuum tube.
6047:
Substitute "1" for a: ( (c & b) ∨ (~c & 1) )
5864:(representing falsity) can be expressed using the stroke:
5795:
The binary connective corresponding to NAND is called the
4748:
Complement for AND: (a & ~a) = 0 or (a & ~a) = F,
4502:
Omitting parentheses with regards to a single-variable NOT
411:, where "co"=1 and Σ=0 as shown in the right-most columns.
399:. For example, one might write down a truth table for how
11071:
state machine (e.g. a Turing machine) to do the counting.
10705:
5135:
4956:
itself is a formula. This idea can be used to generate a
4474:
Commutative law for OR: ( a ∨ b ) ≡ ( b ∨ a )
3418:{\displaystyle \lnot ,\land ,\lor ,\to ,\leftrightarrow }
186:
Relationship between propositional and predicate formulas
11052:
7603:
7524:
7446:
7367:
7288:
7210:
7132:
7054:
6053:
Law of commutation for V: ( (~c) ∨ (c & b) )
6050:
Identity (~c & 1) = ~c: ( (c & b) ∨ (~c) )
5296:
Well-formed formulas versus valid formulas in inferences
2894:
in a wff is assigned an arbitrary truth value { T, F }.
755:; those with a continuous range of behaviors are called
10534:(1912:74) lists three laws of thought that derive from
4736:
Nullity for OR: (a ∨ 1) = 1 or (a ∨ T) = T
4730:
Identity for OR: (a ∨ 0) = a or (a ∨ F) = a
3377:
The classical presentation of propositional logic (see
3327:
Example: Use this set of formula schemas/equivalences:
359:
11497:, Harvard University Press, Cambridge, Massachusetts.
10835:
Rosenbloom and Kleene 1952:73-74 ranks all 11 symbols.
9751:
7917:
4477:
Commutative law for AND: ( a & b ) ≡ ( b & a )
3936:
and closed under all the formula building operations.
3356:
Use 1 to replace "a" with (a ∨ 0): (a ∨ 0)
266:
An algebra of propositions, the propositional calculus
11335:, (Pergamon Press 1963), 1966, (Dover edition 2007),
11009:
Indeed, exhaustive selection between alternatives --
6910:
Reduction by use of the map method (Veitch, Karnaugh)
5996:
5976:
5928:
5873:
5850:
5830:
5761:
5729:
5697:
5665:
4923:
4560:
Laws of evaluation: Identity, nullity, and complement
4335:
3892:
3861:
3830:
3798:
3752:
3712:
3672:
3586:
3566:
3546:
3526:
3492:
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3387:
957:
913:
893:
873:
835:
809:
789:
11485:(pbk.). This book is in print and readily available.
11454:(pbk.). This book is in print and readily available.
7748:
6922:
4739:
Nullity for AND: (a & 0) = 0 or (a & F) = F
4733:
Identity for AND: (a & 1) = a or (a & T) = a
3433:
Each propositional variable in the set is a formula,
942:
Other binary connectives, such as NAND, NOR, and XOR
696:
Truth values in rhetoric, philosophy and mathematics
5370:Example 2 (from Reichenbach via Bertrand Russell):
5300:The notion of valid argument is usually applied to
4782:, eliminating the need for parentheses altogether.
4539:
De Morgan's law for AND: ¬(a ^ b) ≡ (¬a ∨ ¬b)
4457:
976:
Connectives of rhetoric, philosophy and mathematics
169:, behind the rocks."). Thus the simple "primitive"
122:
under discussion, just like an expression such as "
54:A propositional formula is constructed from simple
11208:procedure for obtaining word statements" (p. 185).
6002:
5982:
5954:
5913:
5856:
5836:
5779:
5747:
5715:
5683:
4932:
4552:Absorption (idempotency) for OR: (a ∨ a) ≡ a
4536:De Morgan's law for OR: ¬(a ∨ b) ≡ (¬a ^ ¬b)
3909:
3878:
3847:
3816:
3784:
3727:
3698:
3611:{\displaystyle \land ,\lor ,\to ,\leftrightarrow }
3610:
3572:
3552:
3532:
3512:
3476:
3456:
3417:
3271:
2872:in his "formal statement calculus" L. A valuation
963:
931:
899:
879:
860:{\displaystyle \land ,\lor ,\to ,\leftrightarrow }
859:
818:
795:
11519:1927 2nd edition, paperback edition to *53 1962,
11463:Transactions of the American Mathematical Society
4555:Absorption (idempotency) for AND: (a & a) ≡ a
3910:{\displaystyle {\mathcal {E}}_{\leftrightarrow }}
3429:to be the smallest set of expressions such that:
3233:(demonstrations, examples) for a general formula
13323:
11396:Introduction to the Theory of Switching Circuits
10546:: "Nothing can both be and not be", and (3) The
3633:denote a set of propositional variables and let
3207:LOGICAL EQUIVALENCE: ( (a → b) & (b → a) ) =
649:The simplest type of propositional formula is a
149:
140:For the purposes of the propositional calculus,
11477:, Dover Publications, Inc., Mineola, New York.
11446:, Dover Publications, Inc., Mineola, New York.
11426:, Dover Publications, Inc., Mineola, New York,
4755:
3217:
1674:( IF 'counter is zero' THEN 'go to instruction
945:The ternary connective IF ... THEN ... ELSE ...
376:"Given that consciousness is sufficient for an
74:such as NOT, AND, OR, or IMPLIES; for example:
39:. A propositional formula may also be called a
11287:. Amsterdam: North-Holland Publishing Company.
11265:. Mineola, New York: Dover Publications, Inc.
10288:state 1 with (d =0 & c=0 ), 1 is trapped
5644:
4765:
3917:corresponding to the other binary connectives.
3261:of the definition schema (~SW2 ∨ CON1) =
704:puts all propositions into two broad classes:
11579:
11339:, Dover Publications, Inc. Minola, New York,
10647:that he discovered in Frege's treatment ( cf
10441:state 1 with (d =1 & c=0 ), 1 is trapped
10135:state 0 with ( d=1 & r=0 ), 0 is trapped
9979:state 0 with ( s=0 & r=0 ), 0 is trapped
8629:
4488:Omitting parentheses in strings of AND and OR
11377:, Cambridge University Press, Cambridge UK,
11134:. He gives as example the definition of the
8574:
7815:Idempotency (absorption) [ A ∨ A) = A:
7684:
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5150:
5147:
5144:
5141:
5138:
4977:
3785:{\displaystyle {\mathcal {E}}_{\land }(y,z)}
991:
770:
687:Truth-value assignments, formula evaluations
10591:Essay concerning human understanding (1690)
9709:
7682:
6635:
6604:
3242:Example: In the definition (~a ∨ b) =
3179:definition of a new variable: (c & d) =
11771:
11586:
11572:
11493:1967, 3rd printing with emendations 1976,
11257:
11058:
10997:
9811:
9230:The next simplest case is the "set-reset"
4727:Commutation of equality: (a = b) ≡ (b = a)
3699:{\displaystyle {\mathcal {E}}_{\lnot }(z)}
2790:
1389:(see below). Engineers also use the words
1367:
644:
58:, such as "five is greater than three" or
11412:Computation: Finite and Infinite Machines
10526:
9809:
9807:
9805:
9803:
9801:
9799:
9797:
9794:
9791:
9789:
9787:
9785:
9782:
9779:
9777:
9775:
9772:
9770:
9768:
9765:
9763:
9761:
9759:
9757:
9755:
9753:
8572:
7806:= ( #3 ∨ #7 ∨ #6 ∨ #4 )
5955:{\displaystyle \bot \equiv (\top |\top )}
3503:
3499:
1646:CASE connective: IF ... THEN ... ELSE ...
380:and only conscious entities can pass the
316:Learn how and when to remove this message
10597:(theory of the use of symbols). By 1826
10563:Law of excluded middle: (O ∨ ~(O))
9703:state 1 with s & r simultaneously 1
9022:
9001:
8818:
7752:
6608:
5824:In particular, the zero-ary connectives
5648:
5313:for a formula to be valid but it is not
3925:is defined to be the smallest subset of
3513:{\displaystyle (\alpha \,\Box \,\beta )}
3200:XOR: (~a & b) ∨ (a & ~b) =
3144:
1371:
8728:
6084:
5965:
5384:
4978:
4574:
3961:
3372:
1752:
239:( B(p) AND W(p) ) evaluates to { T, F }
13324:
11593:
11300:A Short Course in Discrete Mathematics
11279:
11190:, is defined in terms of the totality
9245:
9067:
8842:
8682:It helps to think of the formula as a
7924:
6962:
6728:(these are virtually the same thing).
3848:{\displaystyle {\mathcal {E}}_{\lor }}
3037:
11567:
11539:Logic Design with Integrated Circuits
11320:A Mathematical Introduction to Logic.
11112:writing down every one is infeasible.
10560:Law of contradiction: ~(O & ~(O))
8670:Propositional formula with "feedback"
5914:{\displaystyle \top \equiv (a|(a|a))}
5338:( ( (a) & ( (b) → ~(a) ) ≡ ~(b) )
5317:." The only way to find out if it is
4543:
3879:{\displaystyle {\mathcal {E}}_{\to }}
1136:
10913:The Emergence of Logical Empriricism
6737:
5790:
4511:
2931:
2896:
1092:b IS NECESSARY AND SUFFICIENT FOR a
992:
360:Usefulness of propositional formulas
269:
202:or plural) of discourse) and (ii) a
9225:
9052:
7918:Verify reduction with a truth table
7824:( #3 ∨ ∨ ∨ #4 )
7050:Formula in conjunctive normal form
6593:. Some common normal forms include
4527:
3939:
3229:(or "schemata"), that is, they are
932:{\displaystyle (\alpha \to \beta )}
779:. Examples of connectives include:
13:
11424:Mathematical Logic: A First Course
11302:, Dover Publications, Mineola NY,
11263:The Elements of Mathematical Logic
11170:is defined in terms of the notion
10550:: "Everything must be or not be."
9737:& ( ~( c & ~( d ) ) ) ) =
9726:& ( ~( c & ~( d ) ) ) ) =
7765:
5997:
5977:
5946:
5938:
5929:
5874:
5851:
5831:
5739:
5707:
5675:
4948:that has balanced parentheses. If
4927:
4336:Connective seniority (symbol rank)
3896:
3865:
3834:
3756:
3716:
3682:
3676:
3445:
3388:
810:
783:The unary negation connective. If
333:(symbol-formation) rather than in
14:
13368:
11545:
11204:is not really possible to have a
10876:(italics added) Reichenbach p.80.
7749:Create the formula's Karnaugh map
6923:Produce the formula's truth table
5684:{\displaystyle \{\land ,\lnot \}}
3580:is one of the binary connectives
3302:)) ∨ (p & ~(c & ~(q
2815:((s → b) & (b → s)) = (s ↔ b)
829:The classical binary connectives
13305:
11551:
10899:Empiricits eschew the notion of
6738:decimal equivalent of (c, b, a)
5780:{\displaystyle \{\land ,\lor \}}
5716:{\displaystyle \{\lor ,\lnot \}}
4458:Commutative and associative laws
964:{\displaystyle \leftrightarrow }
655:. Propositions that are simple (
274:
11285:Introduction to metamathematics
11238:
11220:
11211:
11197:
11115:
11105:
11096:
11083:
11074:
11064:
11035:
11025:
11016:
11003:
10982:
10829:
10816:
10680:Computation and switching logic
10518:state 1 with ( d=1 & c=1 ):
10056:state 0 with ( d=0 & c=1 ):
9656:state 1 with ( s=1 & r=0 )
9563:state 1 with ( s=0 & r=0 )
9424:state 0 with ( s=0 & r=1 )
9377:state 0 with ( s=0 & r=0 )
9062:to the right of the once-flip.
8679:result: oscillation or memory.
6630:Quine–McCluskey algorithm
6584:
6068:( ~c ∨ b ) is defined as
5748:{\displaystyle \{\to ,\lnot \}}
5343:This is well-formed, but is it
4969:This method locates as "1" the
4964:Example of parenthesis counting
3824:. There are similar operations
3629:operation (Enderton 2002). Let
3457:{\displaystyle (\lnot \alpha )}
3272:Substitution versus replacement
1713:because the second sentence is
135:
10973:
10947:
10937:
10921:
10893:
10879:
10870:
10858:
10849:
10542:: "Whatever is, is.", (2) The
8717:
7790:have no special significance:
6914:Veitch improved the notion of
5949:
5942:
5935:
5908:
5905:
5898:
5891:
5887:
5880:
5733:
5362:that the frog isn't croaking."
4924:
3902:
3871:
3811:
3799:
3779:
3767:
3722:
3713:
3693:
3687:
3605:
3599:
3507:
3493:
3451:
3442:
3412:
3406:
3162:
958:
926:
920:
914:
854:
848:
1:
13266:History of mathematical logic
11251:
10609:over a priority dispute with
8623:
8621:
8619:
8617:
8615:
8613:
8611:
8609:
8604:
8602:
8600:
8598:
8596:
8594:
8592:
8590:
8588:
8586:
8584:
8582:
8580:
8578:
8576:
7739:
7737:
7735:
7733:
7731:
7729:
7727:
7725:
7723:
7721:
7719:
7717:
7715:
7713:
7711:
7709:
7707:
7702:
7700:
7698:
7696:
7694:
7692:
7690:
7688:
7686:
7678:
7599:
7520:
7442:
7363:
7284:
7282:
7206:
7204:
7128:
7126:
3257:CON1, so we would have as an
3193:IMPLICATION: (~a ∨ b) =
1063:b IF AND ONLY IF a; b IFF a
819:{\displaystyle \lnot \alpha }
152:about well-formed formulas).
13191:Primitive recursive function
11465:, Vol. 5 91904) pp. 288-309.
11359:, Birkhäuser Verlag, Basil,
11235:'s student and close friend.
11121:This definition is given by
10842:
10809:
10444:
10367:
10291:
10214:
10138:
10061:
9982:
9905:
9817:
9816:
9659:
9612:
9566:
9519:
9473:
9427:
9380:
9333:
9281:
9244:
9195:
9168:
9142:
9115:
9087:
9066:
8968:
8942:
8916:
8890:
8862:
8841:
8793:
8770:
8746:
8727:
8606:
8500:
8429:
8358:
8287:
8216:
8145:
8074:
8003:
7923:
7741:
7704:
7675:
7596:
7518:
7439:
7360:
6961:
6498:
6415:
6332:
6249:
6152:
5598:
5555:
5512:
5469:
5421:
5420:
5383:
4756:Double negative (involution)
4686:
4649:
4606:
4261:
4201:
4141:
4081:
4011:
3111:
3096:
3081:
3066:
3049:
3036:
3024:
3012:
2987:
2969:
2683:
2579:
2475:
2371:
2267:
2163:
2059:
1955:
1835:
1751:
1326:
1288:
1250:
1212:
1174:
1135:
1103:
1074:
1046:
1018:
1004:
349:or the sentential calculus.
7:
11473:1941 (1995 Dover edition),
11442:1957 (1999 Dover edition),
10962:, North-Holland, New York,
9276:
9274:
9272:
9270:
9268:
9266:
9264:
9260:
9258:
9255:
9253:
9251:
9082:
9080:
9078:
9075:
9073:
9071:
9069:
8857:
8855:
8853:
8851:
8848:
8844:
8741:
8739:
8737:
8735:
8732:
6903:(~a & ~b & ~c)
6767:(~c & ~b & ~a)
6695:cba = (c=1, b=0, a=1) = 101
6660:
6149:
6147:
6145:
6142:
6140:
6138:
6136:
6134:
6132:
6127:
6125:
6123:
6121:
6119:
6117:
6115:
6113:
6111:
6108:
6106:
6104:
6102:
6100:
6098:
6096:
6094:
6090:
6088:
6086:
5645:Reduced sets of connectives
5415:
5404:
5387:
4980:
4766:Well-formed formulas (wffs)
4603:
4591:
3995:
3982:
3980:
3963:
3381:2002) uses the connectives
3044:
3018:
2981:
2922:
1830:
1828:
1826:
1824:
1822:
1820:
1818:
1816:
1814:
1811:
1809:
1807:
1805:
1803:
1801:
1799:
1795:
1793:
1791:
1789:
1785:
1783:
1781:
1779:
1777:
1774:
1772:
1770:
1766:
1764:
1762:
1758:
1756:
1754:
1011:
1007:
1002:
743:Truth values in engineering
708:—true no matter what (e.g.
256:
10:
13373:
12255:Schröder–Bernstein theorem
11982:Monadic predicate calculus
11641:Foundations of mathematics
10915:, Garland Publishing Inc.
10639:. First as the student of
9733:( ( c & d ) ∨ (
9722:( ( c & d ) ∨ (
9262:
9249:
9247:
8846:
8730:
8658:This is an example of the
8630:Impredicative propositions
7999:
7996:
7993:
7990:
7987:
7984:
7981:
7978:
7975:
7972:
7969:
7966:
7963:
7960:
7957:
7954:
7951:
7948:
7945:
7942:
7939:
7043:
7040:
7037:
7034:
7031:
7028:
7025:
7022:
7019:
7016:
7013:
7010:
7007:
7004:
7001:
6998:
6995:
6992:
6989:
6986:
6983:
6980:
6977:
6886:(c & ~b & ~a)
6784:(~c & ~b & a)
6129:
6092:
5412:
5410:
5408:
5406:
5402:
5400:
5398:
5396:
5394:
5392:
4600:
4595:
4593:
4589:
4587:
4584:
4582:
4410:(s, arithmetic successor).
4008:
4006:
4004:
4002:
4000:
3998:
3991:
3989:
3987:
3985:
3978:
3976:
3974:
3972:
3969:
3967:
3817:{\displaystyle (y\land z)}
3046:
3039:
1797:
1768:
1760:
1678:' ELSE 'go to instruction
994:
13301:
13288:Philosophy of mathematics
13237:Automated theorem proving
13219:
13114:
12946:
12839:
12691:
12408:
12384:
12362:Von Neumann–Bernays–Gödel
12307:
12201:
12105:
12003:
11994:
11921:
11856:
11762:
11684:
11601:
11322:Harcourt/Academic Press.
11182:. Thus the definition of
10445:
10368:
10292:
10215:
10139:
10062:
9983:
9906:
9813:
9660:
9613:
9567:
9520:
9474:
9428:
9381:
9334:
9282:
9278:
9196:
9169:
9143:
9116:
9088:
9084:
8997:
8969:
8943:
8917:
8891:
8863:
8859:
8794:
8771:
8747:
8743:
8501:
8430:
8359:
8288:
8217:
8146:
8075:
8008:( ~p & ~d & ~c )
8004:
7058:( ~p & ~d & ~c )
6890:
6873:
6869:(c & ~b & a)
6856:
6839:
6835:(c & b & ~a)
6822:
6818:(~c & b & ~a)
6805:
6801:(~c & b & a)
6788:
6771:
6754:
6499:
6416:
6333:
6250:
6153:
6027:(c, c, a) ≡ (c ∨ a)
5844:(representing truth) and
5599:
5556:
5513:
5470:
5390:
4687:
4650:
4607:
4576:
4462:Both AND and OR obey the
4262:
4202:
4142:
4082:
4012:
3965:
3921:The set of formulas over
3728:{\displaystyle (\lnot z)}
3112:
3097:
3082:
3067:
3050:
2684:
2580:
2476:
2372:
2268:
2164:
2060:
1956:
1836:
1611:
1579:
1547:
1515:
1483:
1457:
1454:
1435:
1423:
1420:
1410:
1327:
1289:
1251:
1213:
1175:
1104:
1075:
1047:
1019:
777:propositional connectives
771:Propositional connectives
11375:Logic for Mathematicians
11355:and Gérard Bornet 1997,
9710:Clocked flip-flop memory
8965:qd & p inconsistent
8939:qd & p inconsistent
8664:impredicative definition
8292:( p & ~d & ~c )
8150:( ~p & d & ~c )
7936:
7933:
7930:
7371:( p & ~d & ~c )
7214:( ~p & d & ~c )
6974:
6971:
6968:
6636:Literal, term and alterm
6605:Reduction to normal form
6038:to be (~c ∨ b) ):
5417:
5130:
5127:
5124:
5121:
5118:
5115:
5112:
5109:
5106:
5103:
5100:
5097:
5094:
5091:
5088:
5085:
5082:
5079:
5076:
5073:
5070:
5067:
5064:
5061:
5058:
5055:
5052:
5049:
5046:
5043:
5040:
5037:
5034:
5031:
5028:
5025:
5022:
5019:
5016:
5013:
5010:
5007:
5004:
5001:
4998:
4995:
4992:
4989:
4986:
4983:
4958:recursive descent parser
4795:
4597:
3993:
3041:
1832:
1787:
1715:not connected in meaning
1397:'s notion (a*a = a) and
1015:
1013:
1009:
1000:
998:
996:
867:. Thus, for example, if
41:propositional expression
12938:Self-verifying theories
12759:Tarski's axiomatization
11710:Tarski's undefinability
11705:incompleteness theorems
11178:is defined in terms of
11000:, pp. 30 and 54ff.
10544:law of noncontradiction
10364:q & p inconsistent
10211:q & p inconsistent
9609:q & p inconsistent
9516:q & p inconsistent
9470:q & p inconsistent
9165:q & p inconsistent
8813:q & p inconsistent
8790:q & p inconsistent
8434:( p & d & ~c )
8363:( p & ~d & c )
8221:( ~p & d & c )
8079:( ~p & ~d & c)
7871:( ∨ ∨ )
7842:( ∨ ∨ )
7528:( p & d & ~c )
7450:( p & ~d & c )
7292:( ~p & d & c )
7136:( ~p & ~d & c)
6675:disjunctive normal form
6599:disjunctive normal form
6595:conjunctive normal form
6030:(c, b, c) ≡ (c & b)
4933:{\displaystyle (\lnot }
4780:reverse Polish notation
4580:
4578:
3533:{\displaystyle \alpha }
3477:{\displaystyle \alpha }
3344:
2791:IDENTITY and evaluation
1667:programming language).
1368:Engineering connectives
880:{\displaystyle \alpha }
796:{\displaystyle \alpha }
645:Propositional variables
378:artificial intelligence
70:, using connectives or
60:propositional variables
27:is a type of syntactic
13332:Propositional calculus
13312:Mathematics portal
12923:Proof of impossibility
12571:propositional variable
11881:Propositional calculus
11510:Alfred North Whitehead
10704:Example: Given binary
10641:Alfred North Whitehead
10557:Law of Identity: O = O
10548:law of excluded middle
10527:Historical development
9029:
9020:
8827:Oscillation with delay
8823:
8505:( p & d & c )
7889:( ∨ ∨ )
7758:
7676:( p & d & c )
7607:( p & d & c )
6934:propositional function
6852:(c & b & a)
6615:
6004:
5984:
5956:
5915:
5858:
5838:
5781:
5749:
5717:
5685:
5655:
4934:
4813:propositional variable
4744:law of excluded middle
3911:
3880:
3849:
3818:
3786:
3729:
3700:
3612:
3574:
3554:
3553:{\displaystyle \beta }
3534:
3520:is a formula whenever
3514:
3478:
3464:is a formula whenever
3458:
3419:
3330:( (a ∨ 0) ≡ a ).
1431:half-adder (no carry)
1377:
1032:b IS SUFFICIENT FOR a
965:
933:
901:
900:{\displaystyle \beta }
881:
861:
820:
797:
652:propositional variable
388:Engineers analyze the
356:for AND, OR and NOT).
347:propositional calculus
296:by rewriting it in an
216:propositional calculus
13181:Kolmogorov complexity
13134:Computably enumerable
13034:Model complete theory
12826:Principia Mathematica
11886:Propositional formula
11715:Banach–Tarski paradox
11558:Propositional formula
11521:Principia Mathematica
11444:Introduction to Logic
11352:Ivor Grattan-Guinness
10865:Principia Mathematica
10653:Principia Mathematica
10626:universe of discourse
10520:q=1 is following d=1
10058:q=0 is following d=0
9026:
9005:
8822:
7756:
7597:(p & d & ~c)
7440:(~p & d & c)
7361:(~p & d & c)
6699:= 1*2 + 0*2 + 1*2 = 5
6623:can be unwieldy, but
6612:
6005:
6003:{\displaystyle \top }
5985:
5983:{\displaystyle \bot }
5957:
5916:
5859:
5857:{\displaystyle \bot }
5839:
5837:{\displaystyle \top }
5801:Principia Mathematica
5782:
5750:
5718:
5686:
5652:
4935:
4404:(arithmetic multiply)
4350:(LOGICAL EQUIVALENCE)
3945:truth-values for its
3912:
3881:
3850:
3819:
3787:
3730:
3701:
3613:
3575:
3573:{\displaystyle \Box }
3555:
3535:
3515:
3479:
3459:
3420:
3333:( (a & ~a) ≡ 0 ).
3218:Axiom and definition
3145:More complex formulas
2979:The two definitions (
2946:) = F if and only if
2824:Principia Mathematica
1375:
1060:a IS NECESSARY FOR b
966:
934:
902:
882:
862:
821:
798:
722:synthetic proposition
25:propositional formula
13129:Church–Turing thesis
13116:Computability theory
12325:continuum hypothesis
11843:Square of opposition
11701:Gödel's completeness
11560:at Wikimedia Commons
11229:The Kleene Symposium
10724:and carry-out (c_out
10720:), their summation Σ
10628:and "0" was nothing.
9730:, but now let p = q:
8662:that result from an
5994:
5974:
5966:IF ... THEN ... ELSE
5926:
5871:
5848:
5828:
5759:
5727:
5695:
5663:
4971:principal connective
4921:
4750:law of contradiction
3890:
3859:
3828:
3796:
3750:
3710:
3670:
3584:
3564:
3544:
3524:
3490:
3468:
3439:
3385:
3373:Inductive definition
3321:logically equivalent
3186:OR: ~(~a & ~b) =
3135:law of contradiction
2862:well-formed formulas
1728:material implication
1405:' notion (a+a = a).
1157:logically equivalent
955:
911:
907:are formulas, so is
891:
871:
833:
807:
787:
13357:Logical expressions
13283:Mathematical object
13174:P versus NP problem
13139:Computable function
12933:Reverse mathematics
12859:Logical consequence
12736:primitive recursive
12731:elementary function
12504:Free/bound variable
12357:Tarski–Grothendieck
11876:Logical connectives
11806:Logical equivalence
11656:Logical consequence
11490:Jean van Heijenoort
11296:Williamson, S. Gill
11150:of the number line
10716:and carry-in ( c_in
9219:state 1 with s = 1
9192:state 1 with s = 0
8712:Macintosh computers
8696:sequential circuits
6024:(c, b, 1) ≡ (c → b)
5817:p ∨ q ≡ ~p|~q
5805:logical equivalence
4386:(THERE EXISTS AN x)
3427:inductively defined
2797:Logical equivalence
1035:b PRECISELY WHEN a
803:is a formula, then
718:verification theory
366:deductive reasoning
245:logical quantifiers
229:domain of discourse
21:propositional logic
13081:Transfer principle
13044:Semantics of logic
13029:Categorical theory
13005:Non-standard model
12519:Logical connective
11646:Information theory
11595:Mathematical logic
10611:Augustus De Morgan
9030:
9021:
8824:
7759:
6692:= c*2 + b*2 + a*2:
6616:
6000:
5980:
5952:
5911:
5854:
5834:
5820:p & q ≡ ~(p|q)
5777:
5745:
5713:
5681:
5656:
5351:then the argument
4930:
4544:Laws of absorption
3907:
3876:
3845:
3814:
3782:
3725:
3696:
3608:
3570:
3550:
3530:
3510:
3474:
3454:
3415:
3336:( (~a ∨ b) =
3022:). In particular (
1656:computation theory
1378:
961:
929:
897:
877:
857:
816:
793:
298:encyclopedic style
285:is written like a
192:predicate calculus
49:sentential formula
13319:
13318:
13251:Abstract category
13054:Theories of truth
12864:Rule of inference
12854:Natural deduction
12835:
12834:
12380:
12379:
12085:Cartesian product
11990:
11989:
11896:Many-valued logic
11871:Boolean functions
11754:Russell's paradox
11729:diagonal argument
11626:First-order logic
11556:Media related to
11535:William E. Wickes
11527:1921 and M. Jean
11365:978-0-8176-5456-6
11292:Bender, Edward A.
11136:least upper bound
10649:Russell's paradox
10524:
10523:
9707:
9706:
9223:
9222:
8995:
8994:
8817:
8816:
8708:register machines
8627:
8626:
7746:
7745:
6932:Technically, the
6907:
6906:
6582:
6581:
5791:The stroke (NAND)
5642:
5641:
5293:
5292:
4724:
4723:
4512:Distributive laws
4322:
4321:
3560:are formulas and
3353:start with "a": a
3127:
3126:
2977:
2976:
2930:
2929:
2788:
2787:
1643:
1642:
1365:
1364:
1162:f IS A tautology
642:
641:
354:distributive laws
326:
325:
318:
108:formal expression
72:logical operators
13364:
13310:
13309:
13261:History of logic
13256:Category of sets
13149:Decision problem
12928:Ordinal analysis
12869:Sequent calculus
12767:Boolean algebras
12707:
12706:
12681:
12652:logical/constant
12406:
12405:
12392:
12315:Zermelo–Fraenkel
12066:Set operations:
12001:
12000:
11938:
11769:
11768:
11749:Löwenheim–Skolem
11636:Formal semantics
11588:
11581:
11574:
11565:
11564:
11555:
11536:
11518:
11516:Bertrand Russell
11512:
11492:
11472:
11459:E. V. Huntington
11441:
11421:
11409:
11407:Marvin L. Minsky
11393:
11372:
11354:
11334:
11333:Goodstein, R. L.
11317:
11297:
11293:
11288:
11276:
11259:Rosenbloom, Paul
11245:
11242:
11236:
11224:
11218:
11215:
11209:
11201:
11195:
11186:, an element of
11119:
11113:
11109:
11103:
11100:
11094:
11087:
11081:
11078:
11072:
11068:
11062:
11056:
11050:
11039:
11033:
11029:
11023:
11020:
11014:
11011:mutual exclusion
11007:
11001:
10995:
10989:
10986:
10980:
10977:
10971:
10951:
10945:
10941:
10935:
10932:sigmoid function
10925:
10919:
10897:
10891:
10883:
10877:
10874:
10868:
10862:
10856:
10853:
10836:
10833:
10827:
10820:
10660:Henry M. Sheffer
10637:Bertrand Russell
10607:William Hamilton
10532:Bertrand Russell
9749:
9748:
9243:
9242:
9226:Flip-flop memory
9065:
9064:
9053:Once-flip memory
9047:transient states
8840:
8839:
8726:
8725:
8704:counter machines
8647:( NOT(s) AND j )
7922:
7921:
7047:Active minterms
6960:
6959:
6735:
6734:
6082:
6081:
6009:
6007:
6006:
6001:
5989:
5987:
5986:
5981:
5961:
5959:
5958:
5953:
5945:
5920:
5918:
5917:
5912:
5901:
5890:
5863:
5861:
5860:
5855:
5843:
5841:
5840:
5835:
5786:
5784:
5783:
5778:
5754:
5752:
5751:
5746:
5722:
5720:
5719:
5714:
5690:
5688:
5687:
5682:
5382:
5381:
4976:
4975:
4939:
4937:
4936:
4931:
4907:
4904:
4901:
4897:
4894:
4891:
4887:
4884:
4881:
4877:
4874:
4871:
4867:
4864:
4861:
4857:
4854:
4851:
4847:
4844:
4841:
4837:
4834:
4831:
4827:
4824:
4821:
4817:
4814:
4811:
4808:
4805:
4802:
4799:
4791:Backus-Naur form
4572:
4571:
4528:De Morgan's laws
4398:(arithmetic sum)
3959:
3958:
3940:Parsing formulas
3916:
3914:
3913:
3908:
3906:
3905:
3900:
3899:
3885:
3883:
3882:
3877:
3875:
3874:
3869:
3868:
3854:
3852:
3851:
3846:
3844:
3843:
3838:
3837:
3823:
3821:
3820:
3815:
3791:
3789:
3788:
3783:
3766:
3765:
3760:
3759:
3746:, the operation
3734:
3732:
3731:
3726:
3705:
3703:
3702:
3697:
3686:
3685:
3680:
3679:
3666:, the operation
3617:
3615:
3614:
3609:
3579:
3577:
3576:
3571:
3559:
3557:
3556:
3551:
3539:
3537:
3536:
3531:
3519:
3517:
3516:
3511:
3483:
3481:
3480:
3475:
3463:
3461:
3460:
3455:
3424:
3422:
3421:
3416:
3035:
3034:
3010:)". Definition (
2971:
2932:
2924:
2897:
1750:
1749:
1661:switch statement
1652:recursion theory
1421:logical product
1408:
1407:
1165:NEITHER a NOR b
990:
989:
970:
968:
967:
962:
938:
936:
935:
930:
906:
904:
903:
898:
886:
884:
883:
878:
866:
864:
863:
858:
825:
823:
822:
817:
802:
800:
799:
794:
738:
728:
415:
414:
321:
314:
310:
307:
301:
278:
277:
270:
131:
13372:
13371:
13367:
13366:
13365:
13363:
13362:
13361:
13337:Boolean algebra
13322:
13321:
13320:
13315:
13304:
13297:
13242:Category theory
13232:Algebraic logic
13215:
13186:Lambda calculus
13124:Church encoding
13110:
13086:Truth predicate
12942:
12908:Complete theory
12831:
12700:
12696:
12692:
12687:
12679:
12399: and
12395:
12390:
12376:
12352:New Foundations
12320:axiom of choice
12303:
12265:Gödel numbering
12205: and
12197:
12101:
11986:
11936:
11917:
11866:Boolean algebra
11852:
11816:Equiconsistency
11781:Classical logic
11758:
11739:Halting problem
11727: and
11703: and
11691: and
11690:
11685:Theorems (
11680:
11597:
11592:
11548:
11534:
11514:
11508:
11488:
11468:
11437:
11417:
11405:
11388:
11370:
11350:
11337:Boolean Algebra
11332:
11315:Enderton, H. B.
11313:
11295:
11291:
11281:Kleene, Stephen
11273:
11254:
11249:
11248:
11243:
11239:
11225:
11221:
11216:
11212:
11202:
11198:
11120:
11116:
11110:
11106:
11101:
11097:
11088:
11084:
11079:
11075:
11069:
11065:
11059:Rosenbloom 1950
11057:
11053:
11044:
11040:
11036:
11030:
11026:
11021:
11017:
11008:
11004:
10998:Rosenbloom 1950
10996:
10992:
10987:
10983:
10978:
10974:
10952:
10948:
10942:
10938:
10926:
10922:
10898:
10894:
10884:
10880:
10875:
10871:
10863:
10859:
10855:Hamilton 1978:1
10854:
10850:
10845:
10840:
10839:
10834:
10830:
10821:
10817:
10812:
10800:Edward F. Moore
10796:George H. Mealy
10784:1952 and 1955,
10764:
10760:
10756:
10752:
10746:
10742:
10738:
10734:
10727:
10723:
10719:
10715:
10711:
10599:Richard Whately
10540:law of identity
10529:
10519:
10057:
9712:
9228:
9055:
9043:
9036:
9000:
8720:
8700:Turing machines
8672:
8632:
7920:
7768:
7766:Reduce minterms
7751:
6925:
6912:
6722:Veitch diagrams
6702:
6698:
6691:
6663:
6638:
6607:
6587:
5995:
5992:
5991:
5975:
5972:
5971:
5968:
5941:
5927:
5924:
5923:
5897:
5886:
5872:
5869:
5868:
5849:
5846:
5845:
5829:
5826:
5825:
5793:
5760:
5757:
5756:
5728:
5725:
5724:
5696:
5693:
5692:
5664:
5661:
5660:
5647:
5298:
4922:
4919:
4918:
4910:
4909:
4905:
4902:
4899:
4895:
4892:
4889:
4885:
4882:
4879:
4875:
4872:
4869:
4865:
4862:
4859:
4855:
4852:
4849:
4845:
4842:
4839:
4835:
4832:
4829:
4825:
4822:
4819:
4815:
4812:
4809:
4806:
4803:
4800:
4797:
4776:Polish notation
4768:
4758:
4568:
4562:
4546:
4530:
4514:
4468:associative law
4464:commutative law
4460:
4338:
3942:
3930:
3901:
3895:
3894:
3893:
3891:
3888:
3887:
3870:
3864:
3863:
3862:
3860:
3857:
3856:
3839:
3833:
3832:
3831:
3829:
3826:
3825:
3797:
3794:
3793:
3761:
3755:
3754:
3753:
3751:
3748:
3747:
3711:
3708:
3707:
3681:
3675:
3674:
3673:
3671:
3668:
3667:
3662:Given a string
3656:
3649:
3638:
3585:
3582:
3581:
3565:
3562:
3561:
3545:
3542:
3541:
3525:
3522:
3521:
3491:
3488:
3487:
3469:
3466:
3465:
3440:
3437:
3436:
3386:
3383:
3382:
3375:
3368:
3339:
3309:
3305:
3301:
3297:
3290:
3286:
3274:
3264:
3256:
3252:
3245:
3223:
3210:
3203:
3196:
3189:
3182:
3171:
3165:
3147:
2893:
2889:
2885:
2848:
2844:
2840:
2793:
1648:
1508:~(b ∨ a)
1391:logical product
1370:
978:
956:
953:
952:
912:
909:
908:
892:
889:
888:
872:
869:
868:
834:
831:
830:
808:
805:
804:
788:
785:
784:
773:
736:
726:
689:
647:
410:
401:binary addition
362:
322:
311:
305:
302:
294:help improve it
291:
279:
275:
268:
259:
196:inner structure
188:
174:too ambiguous.
138:
123:
17:
12:
11:
5:
13370:
13360:
13359:
13354:
13349:
13347:Syntax (logic)
13344:
13339:
13334:
13317:
13316:
13302:
13299:
13298:
13296:
13295:
13290:
13285:
13280:
13275:
13274:
13273:
13263:
13258:
13253:
13244:
13239:
13234:
13229:
13227:Abstract logic
13223:
13221:
13217:
13216:
13214:
13213:
13208:
13206:Turing machine
13203:
13198:
13193:
13188:
13183:
13178:
13177:
13176:
13171:
13166:
13161:
13156:
13146:
13144:Computable set
13141:
13136:
13131:
13126:
13120:
13118:
13112:
13111:
13109:
13108:
13103:
13098:
13093:
13088:
13083:
13078:
13073:
13072:
13071:
13066:
13061:
13051:
13046:
13041:
13039:Satisfiability
13036:
13031:
13026:
13025:
13024:
13014:
13013:
13012:
13002:
13001:
13000:
12995:
12990:
12985:
12980:
12970:
12969:
12968:
12963:
12956:Interpretation
12952:
12950:
12944:
12943:
12941:
12940:
12935:
12930:
12925:
12920:
12910:
12905:
12904:
12903:
12902:
12901:
12891:
12886:
12876:
12871:
12866:
12861:
12856:
12851:
12845:
12843:
12837:
12836:
12833:
12832:
12830:
12829:
12821:
12820:
12819:
12818:
12813:
12812:
12811:
12806:
12801:
12781:
12780:
12779:
12777:minimal axioms
12774:
12763:
12762:
12761:
12750:
12749:
12748:
12743:
12738:
12733:
12728:
12723:
12710:
12708:
12689:
12688:
12686:
12685:
12684:
12683:
12671:
12666:
12665:
12664:
12659:
12654:
12649:
12639:
12634:
12629:
12624:
12623:
12622:
12617:
12607:
12606:
12605:
12600:
12595:
12590:
12580:
12575:
12574:
12573:
12568:
12563:
12553:
12552:
12551:
12546:
12541:
12536:
12531:
12526:
12516:
12511:
12506:
12501:
12500:
12499:
12494:
12489:
12484:
12474:
12469:
12467:Formation rule
12464:
12459:
12458:
12457:
12452:
12442:
12441:
12440:
12430:
12425:
12420:
12415:
12409:
12403:
12386:Formal systems
12382:
12381:
12378:
12377:
12375:
12374:
12369:
12364:
12359:
12354:
12349:
12344:
12339:
12334:
12329:
12328:
12327:
12322:
12311:
12309:
12305:
12304:
12302:
12301:
12300:
12299:
12289:
12284:
12283:
12282:
12275:Large cardinal
12272:
12267:
12262:
12257:
12252:
12238:
12237:
12236:
12231:
12226:
12211:
12209:
12199:
12198:
12196:
12195:
12194:
12193:
12188:
12183:
12173:
12168:
12163:
12158:
12153:
12148:
12143:
12138:
12133:
12128:
12123:
12118:
12112:
12110:
12103:
12102:
12100:
12099:
12098:
12097:
12092:
12087:
12082:
12077:
12072:
12064:
12063:
12062:
12057:
12047:
12042:
12040:Extensionality
12037:
12035:Ordinal number
12032:
12022:
12017:
12016:
12015:
12004:
11998:
11992:
11991:
11988:
11987:
11985:
11984:
11979:
11974:
11969:
11964:
11959:
11954:
11953:
11952:
11942:
11941:
11940:
11927:
11925:
11919:
11918:
11916:
11915:
11914:
11913:
11908:
11903:
11893:
11888:
11883:
11878:
11873:
11868:
11862:
11860:
11854:
11853:
11851:
11850:
11845:
11840:
11835:
11830:
11825:
11820:
11819:
11818:
11808:
11803:
11798:
11793:
11788:
11783:
11777:
11775:
11766:
11760:
11759:
11757:
11756:
11751:
11746:
11741:
11736:
11731:
11719:Cantor's
11717:
11712:
11707:
11697:
11695:
11682:
11681:
11679:
11678:
11673:
11668:
11663:
11658:
11653:
11648:
11643:
11638:
11633:
11628:
11623:
11618:
11617:
11616:
11605:
11603:
11599:
11598:
11591:
11590:
11583:
11576:
11568:
11562:
11561:
11547:
11546:External links
11544:
11543:
11542:
11532:
11506:
11486:
11466:
11455:
11439:Patrick Suppes
11435:
11419:Joel W. Robbin
11415:
11403:
11386:
11371:A. G. Hamilton
11368:
11348:
11330:
11311:
11289:
11277:
11271:
11253:
11250:
11247:
11246:
11237:
11219:
11210:
11196:
11123:Stephen Kleene
11114:
11104:
11095:
11082:
11073:
11063:
11051:
11042:
11034:
11024:
11015:
11002:
10990:
10981:
10972:
10946:
10936:
10920:
10892:
10878:
10869:
10857:
10847:
10846:
10844:
10841:
10838:
10837:
10828:
10814:
10813:
10811:
10808:
10807:
10806:
10803:
10793:
10779:
10776:
10769:
10768:
10767:
10766:
10762:
10758:
10757:) ∨ c_in
10754:
10750:
10747:
10744:
10740:
10736:
10732:
10725:
10721:
10717:
10713:
10709:
10701:
10700:
10697:George Stibitz
10694:
10687:William Eccles
10677:
10676:
10673:
10667:
10630:
10629:
10603:George Bentham
10593:used the word
10567:
10566:
10565:
10564:
10561:
10558:
10528:
10525:
10522:
10521:
10516:
10513:
10511:
10509:
10507:
10505:
10503:
10500:
10498:
10495:
10492:
10489:
10487:
10485:
10482:
10479:
10476:
10474:
10471:
10469:
10466:
10463:
10460:
10458:
10456:
10453:
10450:
10447:
10443:
10442:
10439:
10436:
10434:
10432:
10430:
10428:
10426:
10423:
10421:
10418:
10415:
10412:
10410:
10408:
10405:
10402:
10399:
10397:
10394:
10392:
10389:
10386:
10383:
10381:
10379:
10376:
10373:
10370:
10366:
10365:
10362:
10360:
10358:
10356:
10354:
10352:
10350:
10347:
10345:
10342:
10339:
10336:
10334:
10332:
10329:
10326:
10323:
10321:
10318:
10316:
10313:
10310:
10307:
10305:
10303:
10300:
10297:
10294:
10290:
10289:
10286:
10283:
10281:
10279:
10277:
10275:
10273:
10270:
10268:
10265:
10262:
10259:
10257:
10255:
10252:
10249:
10246:
10244:
10241:
10239:
10236:
10233:
10230:
10228:
10226:
10223:
10220:
10217:
10213:
10212:
10209:
10207:
10205:
10203:
10201:
10199:
10197:
10194:
10192:
10189:
10186:
10183:
10181:
10179:
10176:
10173:
10170:
10168:
10165:
10163:
10160:
10157:
10154:
10152:
10150:
10147:
10144:
10141:
10137:
10136:
10133:
10130:
10128:
10126:
10124:
10122:
10120:
10117:
10115:
10112:
10109:
10106:
10104:
10102:
10099:
10096:
10093:
10091:
10088:
10086:
10083:
10080:
10077:
10075:
10073:
10070:
10067:
10064:
10060:
10059:
10054:
10051:
10049:
10047:
10045:
10043:
10041:
10038:
10036:
10033:
10030:
10027:
10025:
10023:
10020:
10017:
10014:
10012:
10009:
10007:
10004:
10001:
9998:
9996:
9994:
9991:
9988:
9985:
9981:
9980:
9977:
9974:
9972:
9970:
9968:
9966:
9964:
9961:
9959:
9956:
9953:
9950:
9948:
9946:
9943:
9940:
9937:
9935:
9932:
9930:
9927:
9924:
9921:
9919:
9917:
9914:
9911:
9908:
9904:
9903:
9900:
9897:
9894:
9891:
9888:
9885:
9882:
9879:
9876:
9873:
9870:
9867:
9864:
9861:
9858:
9855:
9852:
9849:
9846:
9843:
9840:
9837:
9834:
9831:
9828:
9825:
9822:
9819:
9815:
9814:
9812:
9810:
9808:
9806:
9804:
9802:
9800:
9798:
9796:
9793:
9790:
9788:
9786:
9784:
9781:
9778:
9776:
9774:
9771:
9769:
9767:
9764:
9762:
9760:
9758:
9756:
9754:
9752:
9744:
9743:
9742:
9741:
9731:
9711:
9708:
9705:
9704:
9701:
9698:
9696:
9694:
9692:
9689:
9687:
9684:
9681:
9678:
9676:
9673:
9670:
9668:
9665:
9662:
9658:
9657:
9654:
9651:
9649:
9647:
9645:
9642:
9640:
9637:
9634:
9631:
9629:
9626:
9623:
9621:
9618:
9615:
9611:
9610:
9607:
9605:
9603:
9601:
9599:
9596:
9594:
9591:
9588:
9585:
9583:
9580:
9577:
9575:
9572:
9569:
9565:
9564:
9561:
9558:
9556:
9554:
9552:
9549:
9547:
9544:
9541:
9538:
9536:
9533:
9530:
9528:
9525:
9522:
9518:
9517:
9514:
9512:
9510:
9508:
9506:
9503:
9501:
9498:
9495:
9492:
9490:
9487:
9484:
9482:
9479:
9476:
9472:
9471:
9468:
9466:
9464:
9462:
9460:
9457:
9455:
9452:
9449:
9446:
9444:
9441:
9438:
9436:
9433:
9430:
9426:
9425:
9422:
9419:
9417:
9415:
9413:
9410:
9408:
9405:
9402:
9399:
9397:
9394:
9391:
9389:
9386:
9383:
9379:
9378:
9375:
9372:
9370:
9368:
9366:
9363:
9361:
9358:
9355:
9352:
9350:
9347:
9344:
9342:
9339:
9336:
9332:
9331:
9329:
9326:
9323:
9320:
9317:
9314:
9311:
9308:
9305:
9302:
9299:
9296:
9293:
9290:
9287:
9284:
9280:
9279:
9277:
9275:
9273:
9271:
9269:
9267:
9265:
9263:
9261:
9259:
9257:
9254:
9252:
9250:
9248:
9246:
9227:
9224:
9221:
9220:
9217:
9214:
9212:
9209:
9206:
9203:
9201:
9198:
9194:
9193:
9190:
9187:
9185:
9182:
9179:
9176:
9174:
9171:
9167:
9166:
9163:
9161:
9159:
9156:
9153:
9150:
9148:
9145:
9141:
9140:
9137:
9134:
9132:
9129:
9126:
9123:
9121:
9118:
9114:
9113:
9111:
9108:
9105:
9102:
9099:
9096:
9093:
9090:
9086:
9085:
9083:
9081:
9079:
9077:
9074:
9072:
9070:
9068:
9054:
9051:
9041:
9034:
9017:state diagrams
8999:
8996:
8993:
8992:
8989:
8986:
8984:
8981:
8979:
8976:
8974:
8971:
8967:
8966:
8963:
8960:
8958:
8955:
8953:
8950:
8948:
8945:
8941:
8940:
8937:
8934:
8932:
8929:
8927:
8924:
8922:
8919:
8915:
8914:
8911:
8908:
8906:
8903:
8901:
8898:
8896:
8893:
8889:
8888:
8886:
8883:
8880:
8877:
8874:
8871:
8868:
8865:
8861:
8860:
8858:
8856:
8854:
8852:
8850:
8847:
8845:
8843:
8815:
8814:
8811:
8808:
8806:
8803:
8801:
8798:
8796:
8792:
8791:
8788:
8785:
8783:
8780:
8778:
8775:
8773:
8769:
8768:
8766:
8763:
8760:
8757:
8754:
8751:
8749:
8745:
8744:
8742:
8740:
8738:
8736:
8734:
8731:
8729:
8719:
8716:
8671:
8668:
8649:
8648:
8640:
8639:
8631:
8628:
8625:
8624:
8622:
8620:
8618:
8616:
8614:
8612:
8610:
8608:
8605:
8603:
8601:
8599:
8597:
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8589:
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8581:
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8525:
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8517:
8515:
8512:
8509:
8506:
8503:
8499:
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8496:
8494:
8491:
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8486:
8483:
8480:
8478:
8475:
8473:
8470:
8467:
8464:
8462:
8459:
8457:
8454:
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8448:
8446:
8444:
8441:
8438:
8435:
8432:
8428:
8427:
8425:
8423:
8420:
8418:
8415:
8412:
8409:
8407:
8404:
8402:
8399:
8396:
8393:
8391:
8388:
8386:
8383:
8380:
8377:
8375:
8373:
8370:
8367:
8364:
8361:
8357:
8356:
8354:
8352:
8349:
8347:
8344:
8341:
8338:
8336:
8333:
8331:
8328:
8325:
8322:
8320:
8317:
8315:
8312:
8309:
8306:
8304:
8302:
8299:
8296:
8293:
8290:
8286:
8285:
8283:
8281:
8278:
8276:
8273:
8270:
8267:
8265:
8262:
8260:
8257:
8254:
8251:
8249:
8246:
8244:
8241:
8238:
8235:
8233:
8231:
8228:
8225:
8222:
8219:
8215:
8214:
8212:
8210:
8207:
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8199:
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8180:
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8139:
8136:
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8128:
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8120:
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8115:
8112:
8109:
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8077:
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7989:
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7968:
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7894:
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7890:
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7877:
7876:
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7864:
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7856:
7855:
7854:
7843:
7835:
7834:
7830:
7829:
7828:
7827:
7826:
7825:
7817:
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7812:
7811:
7810:
7809:
7808:
7807:
7796:
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7708:
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7693:
7691:
7689:
7687:
7685:
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7640:
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7627:
7624:
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7608:
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7515:
7513:
7511:
7509:
7507:
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7364:
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7333:
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7328:
7325:
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7317:
7315:
7312:
7309:
7306:
7304:
7302:
7299:
7296:
7293:
7290:
7286:
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7275:
7273:
7271:
7268:
7266:
7263:
7260:
7257:
7255:
7253:
7250:
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7244:
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7208:
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7130:
7129:
7127:
7125:
7123:
7121:
7119:
7117:
7115:
7112:
7110:
7107:
7104:
7101:
7099:
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7094:
7091:
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7083:
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7078:
7075:
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7068:
7065:
7062:
7059:
7056:
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7048:
7045:
7042:
7039:
7036:
7033:
7030:
7027:
7024:
7021:
7018:
7015:
7012:
7009:
7006:
7003:
7000:
6997:
6994:
6991:
6988:
6985:
6982:
6979:
6976:
6973:
6970:
6967:
6964:
6955:
6954:
6953:
6952:
6951:
6950:
6939:
6938:
6924:
6921:
6911:
6908:
6905:
6904:
6901:
6898:
6895:
6892:
6888:
6887:
6884:
6881:
6878:
6875:
6871:
6870:
6867:
6864:
6861:
6858:
6854:
6853:
6850:
6847:
6844:
6841:
6837:
6836:
6833:
6830:
6827:
6824:
6820:
6819:
6816:
6813:
6810:
6807:
6803:
6802:
6799:
6796:
6793:
6790:
6786:
6785:
6782:
6779:
6776:
6773:
6769:
6768:
6765:
6762:
6759:
6756:
6752:
6751:
6748:
6745:
6742:
6739:
6718:Hasse diagrams
6706:
6705:
6704:
6703:
6700:
6696:
6693:
6689:
6662:
6659:
6658:
6657:
6656:
6655:
6652:
6637:
6634:
6606:
6603:
6586:
6583:
6580:
6579:
6577:
6575:
6572:
6569:
6567:
6564:
6562:
6559:
6557:
6554:
6552:
6550:
6547:
6544:
6542:
6539:
6537:
6534:
6532:
6529:
6527:
6524:
6521:
6518:
6516:
6514:
6512:
6510:
6507:
6504:
6501:
6497:
6496:
6494:
6492:
6489:
6486:
6484:
6481:
6479:
6476:
6474:
6471:
6469:
6467:
6464:
6461:
6459:
6456:
6454:
6451:
6449:
6446:
6444:
6441:
6438:
6435:
6433:
6431:
6429:
6427:
6424:
6421:
6418:
6414:
6413:
6411:
6409:
6406:
6403:
6401:
6398:
6396:
6393:
6391:
6388:
6386:
6384:
6381:
6378:
6376:
6373:
6371:
6368:
6366:
6363:
6361:
6358:
6355:
6352:
6350:
6348:
6346:
6344:
6341:
6338:
6335:
6331:
6330:
6328:
6326:
6323:
6320:
6318:
6315:
6313:
6310:
6308:
6305:
6303:
6301:
6298:
6295:
6293:
6290:
6288:
6285:
6283:
6280:
6278:
6275:
6272:
6269:
6267:
6265:
6263:
6261:
6258:
6255:
6252:
6248:
6247:
6244:
6241:
6238:
6235:
6232:
6229:
6226:
6223:
6220:
6217:
6214:
6211:
6208:
6205:
6202:
6199:
6196:
6193:
6190:
6187:
6184:
6181:
6178:
6175:
6172:
6169:
6166:
6164:
6161:
6158:
6155:
6151:
6150:
6148:
6146:
6144:
6141:
6139:
6137:
6135:
6133:
6131:
6128:
6126:
6124:
6122:
6120:
6118:
6116:
6114:
6112:
6110:
6107:
6105:
6103:
6101:
6099:
6097:
6095:
6093:
6091:
6089:
6087:
6085:
6076:
6075:
6074:
6073:
6066:
6063:
6060:
6057:
6054:
6051:
6048:
6045:
6032:
6031:
6028:
6025:
6022:
6021:(c, 0, 1) ≡ ~c
6019:
5999:
5979:
5967:
5964:
5963:
5962:
5951:
5948:
5944:
5940:
5937:
5934:
5931:
5921:
5910:
5907:
5904:
5900:
5896:
5893:
5889:
5885:
5882:
5879:
5876:
5853:
5833:
5822:
5821:
5818:
5815:
5812:
5797:Sheffer stroke
5792:
5789:
5776:
5773:
5770:
5767:
5764:
5744:
5741:
5738:
5735:
5732:
5712:
5709:
5706:
5703:
5700:
5680:
5677:
5674:
5671:
5668:
5646:
5643:
5640:
5639:
5637:
5634:
5631:
5629:
5626:
5623:
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5618:
5615:
5612:
5610:
5608:
5606:
5604:
5601:
5597:
5596:
5594:
5591:
5588:
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5511:
5510:
5508:
5505:
5502:
5500:
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5489:
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5477:
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5472:
5468:
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5464:
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5443:
5440:
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5409:
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5403:
5401:
5399:
5397:
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5391:
5389:
5386:
5380:
5379:
5378:
5377:
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5368:
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5341:
5340:
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5336:
5297:
5294:
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5284:
5281:
5278:
5275:
5272:
5269:
5266:
5263:
5260:
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5236:
5233:
5230:
5227:
5224:
5221:
5218:
5215:
5212:
5209:
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5188:
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5133:
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5120:
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5042:
5039:
5036:
5033:
5030:
5027:
5024:
5021:
5018:
5015:
5012:
5009:
5006:
5003:
5000:
4997:
4994:
4991:
4988:
4985:
4982:
4979:
4960:for formulas.
4929:
4926:
4796:
4787:formal grammar
4772:infix notation
4767:
4764:
4763:
4762:
4757:
4754:
4753:
4752:
4746:
4740:
4737:
4734:
4731:
4728:
4722:
4721:
4719:
4716:
4713:
4711:
4709:
4706:
4704:
4701:
4698:
4695:
4693:
4691:
4689:
4685:
4684:
4682:
4679:
4676:
4674:
4672:
4669:
4667:
4664:
4661:
4658:
4656:
4654:
4652:
4648:
4647:
4644:
4641:
4638:
4635:
4632:
4629:
4626:
4623:
4620:
4617:
4614:
4611:
4609:
4605:
4604:
4602:
4599:
4596:
4594:
4592:
4590:
4588:
4586:
4583:
4581:
4579:
4577:
4575:
4566:
4561:
4558:
4557:
4556:
4553:
4545:
4542:
4541:
4540:
4537:
4529:
4526:
4525:
4524:
4521:
4513:
4510:
4496:
4495:
4485:
4484:
4481:
4478:
4475:
4459:
4456:
4455:
4454:
4453:
4452:
4445:
4444:
4443:
4442:
4441:
4438:
4435:
4432:
4429:
4421:
4414:
4413:
4412:
4411:
4408:
4405:
4402:
4399:
4396:
4393:
4390:
4387:
4384:
4381:
4378:
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4372:
4369:
4366:
4363:
4360:
4357:
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4351:
4348:
4337:
4334:
4320:
4319:
4317:
4315:
4313:
4310:
4308:
4305:
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4300:
4297:
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4043:
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4022:
4019:
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4014:
4010:
4009:
4007:
4005:
4003:
4001:
3999:
3997:
3994:
3992:
3990:
3988:
3986:
3984:
3981:
3979:
3977:
3975:
3973:
3971:
3968:
3966:
3964:
3962:
3957:
3956:
3941:
3938:
3928:
3919:
3918:
3904:
3898:
3873:
3867:
3842:
3836:
3813:
3810:
3807:
3804:
3801:
3781:
3778:
3775:
3772:
3769:
3764:
3758:
3738:Given strings
3736:
3724:
3721:
3718:
3715:
3695:
3692:
3689:
3684:
3678:
3654:
3647:
3636:
3620:
3619:
3607:
3604:
3601:
3598:
3595:
3592:
3589:
3569:
3549:
3529:
3509:
3506:
3502:
3498:
3495:
3485:
3473:
3453:
3450:
3447:
3444:
3434:
3414:
3411:
3408:
3405:
3402:
3399:
3396:
3393:
3390:
3374:
3371:
3370:
3369:
3367:
3366:
3363:
3360:
3357:
3354:
3350:
3348:
3347:
3346:
3343:
3341:
3337:
3334:
3331:
3314:
3313:
3312:
3311:
3307:
3303:
3299:
3295:
3288:
3284:
3273:
3270:
3269:
3268:
3267:
3266:
3262:
3254:
3250:
3243:
3222:
3216:
3215:
3214:
3213:
3212:
3208:
3205:
3201:
3198:
3194:
3191:
3187:
3184:
3180:
3169:
3164:
3161:
3146:
3143:
3131:formal systems
3125:
3124:
3122:
3119:
3116:
3113:
3110:
3109:
3107:
3104:
3101:
3098:
3095:
3094:
3092:
3089:
3086:
3083:
3080:
3079:
3077:
3074:
3071:
3068:
3065:
3064:
3061:
3058:
3055:
3052:
3048:
3047:
3045:
3043:
3040:
3038:
2975:
2974:
2965:
2963:
2928:
2927:
2918:
2916:
2891:
2887:
2883:
2846:
2842:
2838:
2819:
2818:
2817:
2816:
2792:
2789:
2786:
2785:
2782:
2780:
2778:
2775:
2772:
2770:
2767:
2765:
2762:
2760:
2757:
2755:
2752:
2749:
2746:
2744:
2742:
2740:
2737:
2735:
2733:
2730:
2727:
2725:
2722:
2720:
2717:
2715:
2712:
2710:
2707:
2704:
2701:
2699:
2697:
2695:
2692:
2689:
2686:
2682:
2681:
2678:
2676:
2674:
2671:
2668:
2666:
2663:
2661:
2658:
2656:
2653:
2651:
2648:
2645:
2642:
2640:
2638:
2636:
2633:
2631:
2629:
2626:
2623:
2621:
2618:
2616:
2613:
2611:
2608:
2606:
2603:
2600:
2597:
2595:
2593:
2591:
2588:
2585:
2582:
2578:
2577:
2574:
2572:
2570:
2567:
2564:
2562:
2559:
2557:
2554:
2552:
2549:
2547:
2544:
2541:
2538:
2536:
2534:
2532:
2529:
2527:
2525:
2522:
2519:
2517:
2514:
2512:
2509:
2507:
2504:
2502:
2499:
2496:
2493:
2491:
2489:
2487:
2484:
2481:
2478:
2474:
2473:
2470:
2468:
2466:
2463:
2460:
2458:
2455:
2453:
2450:
2448:
2445:
2443:
2440:
2437:
2434:
2432:
2430:
2428:
2425:
2423:
2421:
2418:
2415:
2413:
2410:
2408:
2405:
2403:
2400:
2398:
2395:
2392:
2389:
2387:
2385:
2383:
2380:
2377:
2374:
2370:
2369:
2366:
2364:
2362:
2359:
2356:
2354:
2351:
2349:
2346:
2344:
2341:
2339:
2336:
2333:
2330:
2328:
2326:
2324:
2321:
2319:
2317:
2314:
2311:
2309:
2306:
2304:
2301:
2299:
2296:
2294:
2291:
2288:
2285:
2283:
2281:
2279:
2276:
2273:
2270:
2266:
2265:
2262:
2260:
2258:
2255:
2252:
2250:
2247:
2245:
2242:
2240:
2237:
2235:
2232:
2229:
2226:
2224:
2222:
2220:
2217:
2215:
2213:
2210:
2207:
2205:
2202:
2200:
2197:
2195:
2192:
2190:
2187:
2184:
2181:
2179:
2177:
2175:
2172:
2169:
2166:
2162:
2161:
2158:
2156:
2154:
2151:
2148:
2146:
2143:
2141:
2138:
2136:
2133:
2131:
2128:
2125:
2122:
2120:
2118:
2116:
2113:
2111:
2109:
2106:
2103:
2101:
2098:
2096:
2093:
2091:
2088:
2086:
2083:
2080:
2077:
2075:
2073:
2071:
2068:
2065:
2062:
2058:
2057:
2054:
2052:
2050:
2047:
2044:
2042:
2039:
2037:
2034:
2032:
2029:
2027:
2024:
2021:
2018:
2016:
2014:
2012:
2009:
2007:
2005:
2002:
1999:
1997:
1994:
1992:
1989:
1987:
1984:
1982:
1979:
1976:
1973:
1971:
1969:
1967:
1964:
1961:
1958:
1954:
1953:
1950:
1947:
1944:
1941:
1938:
1935:
1932:
1929:
1926:
1923:
1920:
1917:
1914:
1911:
1908:
1905:
1902:
1900:
1897:
1894:
1891:
1888:
1885:
1882:
1879:
1876:
1873:
1870:
1867:
1864:
1861:
1858:
1855:
1852:
1849:
1847:
1844:
1841:
1838:
1834:
1833:
1831:
1829:
1827:
1825:
1823:
1821:
1819:
1817:
1815:
1813:
1810:
1808:
1806:
1804:
1802:
1800:
1798:
1796:
1794:
1792:
1790:
1788:
1786:
1784:
1782:
1780:
1778:
1776:
1773:
1771:
1769:
1767:
1765:
1763:
1761:
1759:
1757:
1755:
1753:
1724:
1723:
1717:to the first.
1706:
1705:
1694:
1683:
1647:
1644:
1641:
1640:
1637:
1634:
1631:
1628:
1625:
1622:
1619:
1616:
1613:
1609:
1608:
1605:
1602:
1599:
1596:
1593:
1590:
1587:
1584:
1581:
1577:
1576:
1573:
1570:
1567:
1564:
1561:
1558:
1555:
1552:
1549:
1545:
1544:
1541:
1538:
1535:
1532:
1529:
1526:
1523:
1520:
1517:
1513:
1512:
1509:
1506:
1503:
1502:(b ∨ a)
1500:
1497:
1494:
1491:
1488:
1485:
1481:
1480:
1477:
1474:
1471:
1468:
1465:
1462:
1459:
1456:
1452:
1451:
1448:
1446:
1444:
1442:
1440:
1438:
1436:
1433:
1432:
1429:
1427:
1425:
1422:
1419:
1417:
1415:
1413:
1411:
1369:
1366:
1363:
1362:
1359:
1356:
1353:
1350:
1347:
1344:
1341:
1338:
1335:
1332:
1329:
1325:
1324:
1321:
1318:
1315:
1312:
1309:
1306:
1303:
1300:
1297:
1294:
1291:
1287:
1286:
1283:
1280:
1277:
1274:
1271:
1268:
1265:
1262:
1259:
1256:
1253:
1249:
1248:
1245:
1242:
1239:
1236:
1233:
1230:
1227:
1224:
1221:
1218:
1215:
1211:
1210:
1207:
1204:
1201:
1200:(f = formula)
1198:
1195:
1192:
1191:(b ∨ a)
1189:
1188:(b ∧ a)
1186:
1183:
1180:
1177:
1173:
1172:
1169:
1166:
1163:
1160:
1153:
1150:
1147:
1144:
1141:
1138:
1134:
1133:
1131:
1129:
1127:
1125:
1124:biconditional
1122:
1119:
1116:
1113:
1110:
1107:
1105:
1102:
1101:
1099:
1097:
1095:
1093:
1090:
1087:
1084:
1082:
1080:
1078:
1076:
1073:
1072:
1070:
1068:
1066:
1064:
1061:
1058:
1056:
1054:
1052:
1050:
1048:
1045:
1044:
1042:
1040:
1038:
1036:
1033:
1030:
1028:
1026:
1024:
1022:
1020:
1017:
1016:
1014:
1012:
1010:
1008:
1006:
1003:
1001:
999:
997:
995:
993:
977:
974:
973:
972:
960:
949:
946:
943:
940:
928:
925:
922:
919:
916:
896:
876:
856:
853:
850:
847:
844:
841:
838:
827:
815:
812:
792:
772:
769:
688:
685:
646:
643:
640:
639:
636:
633:
630:
628:
625:
622:
619:
615:
614:
611:
608:
605:
603:
600:
597:
594:
590:
589:
586:
583:
580:
578:
575:
572:
569:
565:
564:
561:
558:
555:
553:
550:
547:
544:
540:
539:
536:
533:
530:
528:
525:
522:
519:
515:
514:
511:
508:
505:
503:
500:
497:
494:
490:
489:
486:
483:
480:
478:
475:
472:
469:
465:
464:
461:
458:
455:
453:
450:
447:
444:
440:
439:
436:
433:
430:
428:
425:
422:
419:
413:
412:
408:
390:logic circuits
386:
385:
361:
358:
324:
323:
282:
280:
273:
267:
264:
258:
255:
254:
253:
241:
240:
233:Boolean values
225:
224:
223:
222:
187:
184:
180:
179:
159:
158:
137:
134:
96:
95:
15:
9:
6:
4:
3:
2:
13369:
13358:
13355:
13353:
13350:
13348:
13345:
13343:
13340:
13338:
13335:
13333:
13330:
13329:
13327:
13314:
13313:
13308:
13300:
13294:
13291:
13289:
13286:
13284:
13281:
13279:
13276:
13272:
13269:
13268:
13267:
13264:
13262:
13259:
13257:
13254:
13252:
13248:
13245:
13243:
13240:
13238:
13235:
13233:
13230:
13228:
13225:
13224:
13222:
13218:
13212:
13209:
13207:
13204:
13202:
13201:Recursive set
13199:
13197:
13194:
13192:
13189:
13187:
13184:
13182:
13179:
13175:
13172:
13170:
13167:
13165:
13162:
13160:
13157:
13155:
13152:
13151:
13150:
13147:
13145:
13142:
13140:
13137:
13135:
13132:
13130:
13127:
13125:
13122:
13121:
13119:
13117:
13113:
13107:
13104:
13102:
13099:
13097:
13094:
13092:
13089:
13087:
13084:
13082:
13079:
13077:
13074:
13070:
13067:
13065:
13062:
13060:
13057:
13056:
13055:
13052:
13050:
13047:
13045:
13042:
13040:
13037:
13035:
13032:
13030:
13027:
13023:
13020:
13019:
13018:
13015:
13011:
13010:of arithmetic
13008:
13007:
13006:
13003:
12999:
12996:
12994:
12991:
12989:
12986:
12984:
12981:
12979:
12976:
12975:
12974:
12971:
12967:
12964:
12962:
12959:
12958:
12957:
12954:
12953:
12951:
12949:
12945:
12939:
12936:
12934:
12931:
12929:
12926:
12924:
12921:
12918:
12917:from ZFC
12914:
12911:
12909:
12906:
12900:
12897:
12896:
12895:
12892:
12890:
12887:
12885:
12882:
12881:
12880:
12877:
12875:
12872:
12870:
12867:
12865:
12862:
12860:
12857:
12855:
12852:
12850:
12847:
12846:
12844:
12842:
12838:
12828:
12827:
12823:
12822:
12817:
12816:non-Euclidean
12814:
12810:
12807:
12805:
12802:
12800:
12799:
12795:
12794:
12792:
12789:
12788:
12786:
12782:
12778:
12775:
12773:
12770:
12769:
12768:
12764:
12760:
12757:
12756:
12755:
12751:
12747:
12744:
12742:
12739:
12737:
12734:
12732:
12729:
12727:
12724:
12722:
12719:
12718:
12716:
12712:
12711:
12709:
12704:
12698:
12693:Example
12690:
12682:
12677:
12676:
12675:
12672:
12670:
12667:
12663:
12660:
12658:
12655:
12653:
12650:
12648:
12645:
12644:
12643:
12640:
12638:
12635:
12633:
12630:
12628:
12625:
12621:
12618:
12616:
12613:
12612:
12611:
12608:
12604:
12601:
12599:
12596:
12594:
12591:
12589:
12586:
12585:
12584:
12581:
12579:
12576:
12572:
12569:
12567:
12564:
12562:
12559:
12558:
12557:
12554:
12550:
12547:
12545:
12542:
12540:
12537:
12535:
12532:
12530:
12527:
12525:
12522:
12521:
12520:
12517:
12515:
12512:
12510:
12507:
12505:
12502:
12498:
12495:
12493:
12490:
12488:
12485:
12483:
12480:
12479:
12478:
12475:
12473:
12470:
12468:
12465:
12463:
12460:
12456:
12453:
12451:
12450:by definition
12448:
12447:
12446:
12443:
12439:
12436:
12435:
12434:
12431:
12429:
12426:
12424:
12421:
12419:
12416:
12414:
12411:
12410:
12407:
12404:
12402:
12398:
12393:
12387:
12383:
12373:
12370:
12368:
12365:
12363:
12360:
12358:
12355:
12353:
12350:
12348:
12345:
12343:
12340:
12338:
12337:Kripke–Platek
12335:
12333:
12330:
12326:
12323:
12321:
12318:
12317:
12316:
12313:
12312:
12310:
12306:
12298:
12295:
12294:
12293:
12290:
12288:
12285:
12281:
12278:
12277:
12276:
12273:
12271:
12268:
12266:
12263:
12261:
12258:
12256:
12253:
12250:
12246:
12242:
12239:
12235:
12232:
12230:
12227:
12225:
12222:
12221:
12220:
12216:
12213:
12212:
12210:
12208:
12204:
12200:
12192:
12189:
12187:
12184:
12182:
12181:constructible
12179:
12178:
12177:
12174:
12172:
12169:
12167:
12164:
12162:
12159:
12157:
12154:
12152:
12149:
12147:
12144:
12142:
12139:
12137:
12134:
12132:
12129:
12127:
12124:
12122:
12119:
12117:
12114:
12113:
12111:
12109:
12104:
12096:
12093:
12091:
12088:
12086:
12083:
12081:
12078:
12076:
12073:
12071:
12068:
12067:
12065:
12061:
12058:
12056:
12053:
12052:
12051:
12048:
12046:
12043:
12041:
12038:
12036:
12033:
12031:
12027:
12023:
12021:
12018:
12014:
12011:
12010:
12009:
12006:
12005:
12002:
11999:
11997:
11993:
11983:
11980:
11978:
11975:
11973:
11970:
11968:
11965:
11963:
11960:
11958:
11955:
11951:
11948:
11947:
11946:
11943:
11939:
11934:
11933:
11932:
11929:
11928:
11926:
11924:
11920:
11912:
11909:
11907:
11904:
11902:
11899:
11898:
11897:
11894:
11892:
11889:
11887:
11884:
11882:
11879:
11877:
11874:
11872:
11869:
11867:
11864:
11863:
11861:
11859:
11858:Propositional
11855:
11849:
11846:
11844:
11841:
11839:
11836:
11834:
11831:
11829:
11826:
11824:
11821:
11817:
11814:
11813:
11812:
11809:
11807:
11804:
11802:
11799:
11797:
11794:
11792:
11789:
11787:
11786:Logical truth
11784:
11782:
11779:
11778:
11776:
11774:
11770:
11767:
11765:
11761:
11755:
11752:
11750:
11747:
11745:
11742:
11740:
11737:
11735:
11732:
11730:
11726:
11722:
11718:
11716:
11713:
11711:
11708:
11706:
11702:
11699:
11698:
11696:
11694:
11688:
11683:
11677:
11674:
11672:
11669:
11667:
11664:
11662:
11659:
11657:
11654:
11652:
11649:
11647:
11644:
11642:
11639:
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11503:0-674-32449-8
11500:
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11491:
11487:
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11483:0-486-28462-X
11480:
11476:
11471:
11470:Alfred Tarski
11467:
11464:
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11456:
11453:
11452:0-486-40687-3
11449:
11445:
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11436:
11433:
11432:0-486-45018-X
11429:
11425:
11420:
11416:
11413:
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11404:
11401:
11400:Willard Quine
11397:
11392:
11387:
11384:
11383:0-521-21838-1
11380:
11376:
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11345:0-486-45894-6
11342:
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11325:
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11308:0-486-43946-1
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11067:
11061:, p. 32.
11060:
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10968:0-444-00259-6
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10824:intuitionists
10819:
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10797:
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10787:
10783:
10782:Willard Quine
10780:
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10633:Gottlob Frege
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9139:state 0, s=0
9138:
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9060:state diagram
9050:
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6916:Venn diagrams
6902:
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6879:
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6726:Karnaugh maps
6723:
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6625:Karnaugh maps
6622:
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4373:
4370:
4367:
4364:
4361:
4358:
4356:(IMPLICATION)
4355:
4352:
4349:
4346:
4345:
4344:
4343:
4342:
4333:
4331:
4330:axiom schemas
4326:
4318:
4316:
4314:
4311:
4309:
4306:
4303:
4301:
4298:
4296:
4293:
4291:
4288:
4286:
4283:
4280:
4277:
4275:
4272:
4270:
4268:
4265:
4258:
4256:
4254:
4251:
4249:
4246:
4243:
4241:
4238:
4236:
4233:
4231:
4228:
4226:
4223:
4220:
4217:
4215:
4212:
4210:
4208:
4205:
4198:
4196:
4194:
4191:
4189:
4186:
4183:
4181:
4178:
4176:
4173:
4171:
4168:
4166:
4163:
4160:
4157:
4155:
4152:
4150:
4148:
4145:
4138:
4136:
4134:
4131:
4129:
4126:
4123:
4121:
4118:
4116:
4113:
4111:
4108:
4106:
4103:
4100:
4097:
4095:
4092:
4090:
4088:
4085:
4077:
4074:
4071:
4068:
4065:
4062:
4059:
4056:
4053:
4050:
4047:
4044:
4041:
4038:
4035:
4032:
4029:
4026:
4023:
4020:
4018:
4015:
3960:
3953:
3952:
3951:
3948:
3937:
3935:
3931:
3924:
3840:
3808:
3805:
3802:
3776:
3773:
3770:
3762:
3745:
3741:
3737:
3719:
3690:
3665:
3661:
3660:
3659:
3657:
3650:
3643:
3639:
3632:
3628:
3623:
3602:
3596:
3593:
3590:
3587:
3567:
3547:
3527:
3504:
3500:
3496:
3486:
3471:
3448:
3435:
3432:
3431:
3430:
3428:
3409:
3403:
3400:
3397:
3394:
3391:
3380:
3364:
3361:
3358:
3355:
3352:
3351:
3349:
3345:( ~(~a) ≡ a )
3342:
3335:
3332:
3329:
3328:
3326:
3325:
3324:
3322:
3318:
3293:
3292:
3282:
3281:
3280:
3278:
3260:
3248:
3247:
3241:
3240:
3239:
3236:
3232:
3228:
3221:
3206:
3199:
3192:
3190:(a ∨ b)
3185:
3178:
3177:
3176:
3175:
3174:
3160:
3157:
3156:Karnaugh maps
3151:
3142:
3140:
3136:
3132:
3123:
3120:
3117:
3114:
3108:
3105:
3102:
3099:
3093:
3090:
3087:
3084:
3078:
3075:
3072:
3069:
3062:
3059:
3056:
3053:
3033:
3031:
3027:
3026:
3021:
3020:
3015:
3014:
3009:
3005:
3002:
2998:
2994:
2990:
2989:
2984:
2983:
2973:
2966:
2964:
2961:
2957:
2953:
2949:
2945:
2941:
2937:
2934:
2933:
2926:
2919:
2917:
2914:
2910:
2906:
2902:
2899:
2898:
2895:
2881:
2880:
2875:
2871:
2867:
2863:
2859:
2854:
2852:
2835:
2831:
2829:
2828:Leibniz's law
2825:
2814:
2813:
2811:
2807:
2806:
2805:
2802:
2798:
2783:
2781:
2779:
2776:
2773:
2771:
2768:
2766:
2763:
2761:
2758:
2756:
2753:
2750:
2747:
2745:
2743:
2741:
2738:
2736:
2734:
2731:
2728:
2726:
2723:
2721:
2718:
2716:
2713:
2711:
2708:
2705:
2702:
2700:
2698:
2696:
2693:
2690:
2687:
2679:
2677:
2675:
2672:
2669:
2667:
2664:
2662:
2659:
2657:
2654:
2652:
2649:
2646:
2643:
2641:
2639:
2637:
2634:
2632:
2630:
2627:
2624:
2622:
2619:
2617:
2614:
2612:
2609:
2607:
2604:
2601:
2598:
2596:
2594:
2592:
2589:
2586:
2583:
2575:
2573:
2571:
2568:
2565:
2563:
2560:
2558:
2555:
2553:
2550:
2548:
2545:
2542:
2539:
2537:
2535:
2533:
2530:
2528:
2526:
2523:
2520:
2518:
2515:
2513:
2510:
2508:
2505:
2503:
2500:
2497:
2494:
2492:
2490:
2488:
2485:
2482:
2479:
2471:
2469:
2467:
2464:
2461:
2459:
2456:
2454:
2451:
2449:
2446:
2444:
2441:
2438:
2435:
2433:
2431:
2429:
2426:
2424:
2422:
2419:
2416:
2414:
2411:
2409:
2406:
2404:
2401:
2399:
2396:
2393:
2390:
2388:
2386:
2384:
2381:
2378:
2375:
2367:
2365:
2363:
2360:
2357:
2355:
2352:
2350:
2347:
2345:
2342:
2340:
2337:
2334:
2331:
2329:
2327:
2325:
2322:
2320:
2318:
2315:
2312:
2310:
2307:
2305:
2302:
2300:
2297:
2295:
2292:
2289:
2286:
2284:
2282:
2280:
2277:
2274:
2271:
2263:
2261:
2259:
2256:
2253:
2251:
2248:
2246:
2243:
2241:
2238:
2236:
2233:
2230:
2227:
2225:
2223:
2221:
2218:
2216:
2214:
2211:
2208:
2206:
2203:
2201:
2198:
2196:
2193:
2191:
2188:
2185:
2182:
2180:
2178:
2176:
2173:
2170:
2167:
2159:
2157:
2155:
2152:
2149:
2147:
2144:
2142:
2139:
2137:
2134:
2132:
2129:
2126:
2123:
2121:
2119:
2117:
2114:
2112:
2110:
2107:
2104:
2102:
2099:
2097:
2094:
2092:
2089:
2087:
2084:
2081:
2078:
2076:
2074:
2072:
2069:
2066:
2063:
2055:
2053:
2051:
2048:
2045:
2043:
2040:
2038:
2035:
2033:
2030:
2028:
2025:
2022:
2019:
2017:
2015:
2013:
2010:
2008:
2006:
2003:
2000:
1998:
1995:
1993:
1990:
1988:
1985:
1983:
1980:
1977:
1974:
1972:
1970:
1968:
1965:
1962:
1959:
1951:
1948:
1945:
1942:
1939:
1936:
1933:
1930:
1927:
1924:
1921:
1918:
1915:
1912:
1909:
1906:
1903:
1901:
1898:
1895:
1892:
1889:
1886:
1883:
1880:
1877:
1874:
1871:
1868:
1865:
1862:
1859:
1856:
1853:
1850:
1848:
1845:
1842:
1839:
1748:
1746:
1742:
1737:
1731:
1729:
1720:
1719:
1718:
1716:
1712:
1703:
1699:
1695:
1692:
1688:
1684:
1681:
1677:
1673:
1672:
1671:
1668:
1666:
1662:
1657:
1653:
1638:
1635:
1632:
1629:
1626:
1623:
1620:
1617:
1614:
1610:
1606:
1603:
1600:
1597:
1594:
1591:
1588:
1585:
1582:
1578:
1574:
1571:
1568:
1565:
1562:
1559:
1556:
1553:
1550:
1546:
1542:
1539:
1536:
1533:
1530:
1527:
1524:
1521:
1518:
1514:
1510:
1507:
1505:~(b & a)
1504:
1501:
1498:
1495:
1492:
1489:
1486:
1482:
1478:
1475:
1472:
1469:
1466:
1463:
1460:
1453:
1450:exclusive OR
1449:
1447:
1445:
1443:
1441:
1439:
1437:
1434:
1430:
1428:
1426:
1418:
1416:
1414:
1412:
1409:
1406:
1404:
1400:
1396:
1392:
1388:
1387:Karnaugh maps
1384:
1374:
1360:
1357:
1354:
1351:
1348:
1345:
1342:
1339:
1336:
1333:
1330:
1322:
1319:
1316:
1313:
1310:
1307:
1304:
1301:
1298:
1295:
1292:
1284:
1281:
1278:
1275:
1272:
1269:
1266:
1263:
1260:
1257:
1254:
1246:
1243:
1240:
1237:
1234:
1231:
1228:
1225:
1222:
1219:
1216:
1208:
1205:
1202:
1199:
1196:
1193:
1190:
1187:
1184:
1181:
1178:
1171:exclusive OR
1170:
1167:
1164:
1161:
1158:
1154:
1151:
1148:
1145:
1142:
1139:
1132:
1130:
1128:
1126:
1123:
1120:
1117:
1114:
1111:
1108:
1106:
1100:
1098:
1096:
1094:
1091:
1088:
1086:inclusive OR
1085:
1083:
1081:
1079:
1077:
1071:
1069:
1067:
1065:
1062:
1059:
1057:
1055:
1053:
1051:
1049:
1043:
1041:
1039:
1037:
1034:
1031:
1029:
1027:
1025:
1023:
1021:
988:
985:
983:
950:
947:
944:
941:
923:
917:
894:
874:
851:
845:
842:
839:
836:
828:
826:is a formula.
813:
790:
782:
781:
780:
778:
768:
764:
762:
758:
754:
750:
745:
744:
740:
733:
729:
723:
719:
715:
711:
707:
703:
698:
697:
693:
684:
682:
678:
674:
670:
666:
662:
658:
654:
653:
637:
634:
631:
629:
626:
623:
620:
617:
616:
612:
609:
606:
604:
601:
598:
595:
592:
591:
587:
584:
581:
579:
576:
573:
570:
567:
566:
562:
559:
556:
554:
551:
548:
545:
542:
541:
537:
534:
531:
529:
526:
523:
520:
517:
516:
512:
509:
506:
504:
501:
498:
495:
492:
491:
487:
484:
481:
479:
476:
473:
470:
467:
466:
462:
459:
456:
454:
451:
448:
445:
442:
441:
437:
434:
431:
429:
426:
423:
420:
417:
416:
406:
405:
404:
402:
398:
393:
391:
383:
379:
375:
374:
373:
371:
367:
364:Analysis: In
357:
355:
350:
348:
342:
338:
336:
332:
320:
317:
309:
299:
295:
289:
288:
283:This section
281:
272:
271:
263:
251:
250:
249:
246:
238:
237:
236:
234:
230:
220:
219:
217:
213:
212:
211:
209:
208:concatenation
205:
201:
197:
193:
183:
177:
176:
175:
172:
168:
164:
155:
154:
153:
151:
147:
143:
133:
130:
126:
121:
120:formal object
117:
113:
109:
105:
101:
93:
89:
85:
81:
77:
76:
75:
73:
69:
65:
61:
57:
52:
50:
46:
42:
38:
34:
30:
26:
22:
16:Logic formula
13352:Propositions
13303:
13101:Ultraproduct
12948:Model theory
12913:Independence
12849:Formal proof
12841:Proof theory
12824:
12797:
12754:real numbers
12726:second-order
12637:Substitution
12514:Metalanguage
12455:conservative
12428:Axiom schema
12372:Constructive
12342:Morse–Kelley
12308:Set theories
12287:Aleph number
12280:inaccessible
12186:Grothendieck
12070:intersection
11957:Higher-order
11945:Second-order
11891:Truth tables
11885:
11848:Venn diagram
11631:Formal proof
11538:
11520:
11494:
11474:
11462:
11443:
11423:
11422:1969, 1997,
11411:
11395:
11374:
11356:
11336:
11319:
11299:
11284:
11262:
11240:
11228:
11222:
11213:
11205:
11199:
11191:
11187:
11183:
11179:
11175:
11171:
11167:
11166:), l.u.b. =
11163:
11159:
11155:
11151:
11148:Dedekind cut
11143:
11139:
11117:
11107:
11098:
11090:
11085:
11076:
11066:
11054:
11047:metalanguage
11037:
11027:
11018:
11010:
11005:
10993:
10988:Robbin p. 3.
10984:
10975:
10959:
10954:
10949:
10939:
10923:
10912:
10900:
10895:
10887:
10881:
10872:
10860:
10851:
10831:
10818:
10786:E. W. Veitch
10691:F. W. Jordan
10679:
10678:
10652:
10631:
10619:
10615:George Boole
10590:
10578:
10576:
10572:Venn diagram
10568:
10530:
9902:Description
9745:
9738:
9734:
9727:
9723:
9713:
9236:
9229:
9056:
9039:
9031:
9012:
9009:total states
9008:
8835:
8831:ad infinitum
8830:
8826:
8825:
8721:
8693:
8681:
8677:
8673:
8657:
8652:
8650:
8641:
8633:
7907:
7851:
7848:
7845:
7803:
7788:
7780:
7776:
7769:
7760:
6956:
6940:
6931:
6926:
6913:
6730:
6707:
6679:
6672:
6664:
6639:
6621:truth tables
6617:
6591:normal forms
6590:
6588:
6585:Normal forms
6077:
6069:
6035:
6033:
5969:
5823:
5814:p → q ≡ p|~q
5804:
5800:
5794:
5657:
5359:
5352:
5348:
5344:
5322:
5321:well-formed
5318:
5314:
5310:
5306:
5299:
4970:
4968:
4963:
4962:
4953:
4949:
4945:
4941:
4917:begins with
4914:
4911:
4784:
4769:
4563:
4547:
4531:
4515:
4501:
4500:
4497:
4487:
4486:
4461:
4415:
4339:
4327:
4323:
3946:
3943:
3933:
3926:
3922:
3920:
3743:
3739:
3663:
3652:
3645:
3641:
3634:
3630:
3624:
3621:
3376:
3320:
3316:
3315:
3277:Substitution
3276:
3275:
3265:(SW2 → CON1)
3258:
3234:
3230:
3224:
3219:
3166:
3152:
3148:
3138:
3128:
3029:
3023:
3017:
3011:
3007:
3003:
3000:
2996:
2992:
2986:
2980:
2978:
2967:
2959:
2955:
2951:
2947:
2943:
2939:
2935:
2920:
2912:
2908:
2904:
2900:
2877:
2873:
2869:
2865:
2857:
2855:
2851:modus ponens
2836:
2832:
2823:
2820:
2809:
2800:
2794:
1740:
1735:
1732:
1725:
1714:
1711:non sequitur
1710:
1707:
1701:
1697:
1690:
1686:
1679:
1675:
1669:
1649:
1499:(b & a)
1424:logical sum
1398:
1390:
1382:
1379:
1152:b IMPLIES a
1121:implication
1118:disjunction
1115:conjunction
1089:IF b THEN a
1005:b only if a
986:
982:truth tables
979:
774:
765:
746:
742:
741:
731:
725:
713:
705:
699:
695:
694:
690:
680:
676:
672:
668:
664:
660:
650:
648:
397:truth tables
394:
387:
370:truth tables
363:
351:
343:
339:
327:
312:
303:
284:
260:
242:
226:
215:
195:
189:
181:
166:
162:
160:
142:propositions
141:
139:
136:Propositions
128:
124:
111:
103:
97:
91:
87:
83:
79:
67:
63:
56:propositions
53:
48:
44:
40:
24:
18:
13211:Type theory
13159:undecidable
13091:Truth value
12978:equivalence
12657:non-logical
12270:Enumeration
12260:Isomorphism
12207:cardinality
12191:Von Neumann
12156:Ultrafilter
12121:Uncountable
12055:equivalence
11972:Quantifiers
11962:Fixed-point
11931:First-order
11811:Consistency
11796:Proposition
11773:Traditional
11744:Lindström's
11734:Compactness
11676:Type theory
11621:Cardinality
11233:Alan Turing
11080:Robbin p. 7
10798:(1955) and
10790:M. Karnaugh
10773:Alan Turing
10662:(1921) and
9028:remains 0).
8718:Oscillation
5349:implication
5307:well-formed
4380:(FOR ALL x)
3932:containing
3317:Replacement
3294:(c & (q
3163:Definitions
2999:) does not
2858:valuation v
1745:multiplexer
1455:row number
1399:logical sum
1168:b stroke a
382:Turing test
248:statement:
221:p|W AND p|B
116:proposition
104:proposition
100:mathematics
86:) IMPLIES (
37:truth value
33:well formed
13342:Statements
13326:Categories
13022:elementary
12715:arithmetic
12583:Quantifier
12561:functional
12433:Expression
12151:Transitive
12095:identities
12080:complement
12013:hereditary
11996:Set theory
11252:References
11174:, whereas
11146:. Given a
11127:Kurt Gödel
11091:conclusive
11045:is in the
10928:Neural net
10909:David Hume
10905:John Locke
10788:1952, and
10739:) XOR c_in
10664:Jean Nicod
10613:"inspired
10587:John Locke
10583:syllogisms
10538:: (1) The
6714:hypercubes
6018:(c, b, a):
5315:sufficient
5302:inferences
4392:(IDENTITY)
3340:(a → b) ).
2954:) = T and
2810:definition
1458:variables
1203:(a NOR b)
1185:¬(a)
1182:¬(b)
1137:variables
761:comparator
749:robustness
702:empiricist
171:assertions
163:particular
13293:Supertask
13196:Recursion
13154:decidable
12988:saturated
12966:of models
12889:deductive
12884:axiomatic
12804:Hilbert's
12791:Euclidean
12772:canonical
12695:axiomatic
12627:Signature
12556:Predicate
12445:Extension
12367:Ackermann
12292:Operation
12171:Universal
12161:Recursive
12136:Singleton
12131:Inhabited
12116:Countable
12106:Types of
12090:power set
12060:partition
11977:Predicate
11923:Predicate
11838:Syllogism
11828:Soundness
11801:Inference
11791:Tautology
11693:paradoxes
11391:McCluskey
11367:(Boston).
11318:, 2002,
10888:valuation
10843:Citations
10810:Footnotes
10761:) = c_out
10670:Emil Post
10595:semiotics
10536:Aristotle
9719:Examples
9232:flip-flop
9013:transient
8714:, etc.).
8684:black box
8660:paradoxes
7928:Minterms
6966:Minterms
6710:Gray code
6648:Examples
5998:⊤
5978:⊥
5947:⊤
5939:⊤
5933:≡
5930:⊥
5878:≡
5875:⊤
5852:⊥
5832:⊤
5772:∨
5766:∧
5740:¬
5734:→
5708:¬
5702:∨
5676:¬
5670:∧
5311:necessary
4928:¬
4761:¬(¬a) ≡ a
4447:Example:
3903:↔
3872:→
3841:∨
3806:∧
3763:∧
3717:¬
3683:¬
3606:↔
3600:→
3594:∨
3588:∧
3568:◻
3548:β
3528:α
3505:β
3501:◻
3497:α
3472:α
3449:α
3446:¬
3413:↔
3407:→
3401:∨
3395:∧
3389:¬
3211:( a ≡ b )
1159:TO a ***
1112:negation
1109:negation
959:↔
924:β
921:→
918:α
895:β
875:α
855:↔
849:→
843:∨
837:∧
814:α
811:¬
791:α
714:synthetic
710:tautology
335:semantics
306:June 2021
204:predicate
146:recursive
31:which is
13278:Logicism
13271:timeline
13247:Concrete
13106:Validity
13076:T-schema
13069:Kripke's
13064:Tarski's
13059:semantic
13049:Strength
12998:submodel
12993:spectrum
12961:function
12809:Tarski's
12798:Elements
12785:geometry
12741:Robinson
12662:variable
12647:function
12620:spectrum
12610:Sentence
12566:variable
12509:Language
12462:Relation
12423:Automata
12413:Alphabet
12397:language
12251:-jection
12229:codomain
12215:Function
12176:Universe
12146:Infinite
12050:Relation
11833:Validity
11823:Argument
11721:theorem,
11298:, 2005,
11283:(1952).
11261:(1950).
11138:(l.u.b)
11132:analysis
11032:values."
10901:a priori
10645:antinomy
9848:∨
9298:∨
9101:∨
8991:state 0
8913:state 1
8688:function
7976:∨
7958:∨
7850:∨
7847:∨
7772:literals
6996:∨
6750:minterm
6685:Example
6668:minterms
6661:Minterms
6072:Q. E. D.
6012:relation
5811:~p ≡ p|p
3792:returns
3706:returns
3379:Enderton
3306:& ~q
3298:& ~q
3287:& ~q
3259:instance
3253:SW2, b =
3139:complete
2879:function
1922:∨
1484:b*2+a*2
1383:minterms
1209:various
1197:(b ↔ a)
1194:(b → a)
1146:b AND a
706:analytic
432:(b+a)+ci
257:Identity
200:singular
82:AND NOT
62:such as
45:sentence
13220:Related
13017:Diagram
12915: (
12894:Hilbert
12879:Systems
12874:Theorem
12752:of the
12697:systems
12477:Formula
12472:Grammar
12388: (
12332:General
12045:Forcing
12030:Element
11950:Monadic
11725:paradox
11666:Theorem
11602:General
11525:Sheffer
11434:(pbk.).
11125:. Both
10753:& b
10728:) are:
10579:algebra
9042:delayed
9035:delayed
7762:phase.
6716:called
6642:literal
6036:defined
5360:implies
4903:formula
4893:formula
4883:formula
4873:formula
4863:formula
4853:formula
4843:formula
4833:formula
4823:formula
4801:formula
4565:~(a)) =
4506:literal
4365:∨
3627:closure
3484:is, and
3227:schemas
3220:schemas
3204:(a ⊕ b)
3197:(a → b)
3042:v(A→B)
3030:assigns
2985:) and (
2864:(wffs)
2860:of any
2801:logical
1736:selects
1663:in the
1149:b OR a
753:digital
712:), and
292:Please
112:denotes
47:, or a
29:formula
12983:finite
12746:Skolem
12699:
12674:Theory
12642:Symbol
12632:String
12615:atomic
12492:ground
12487:closed
12482:atomic
12438:ground
12401:syntax
12297:binary
12224:domain
12141:Finite
11906:finite
11764:Logics
11723:
11671:Theory
11537:1968,
11501:
11481:
11450:
11430:
11410:1967,
11394:1965,
11389:E. J.
11381:
11373:1978,
11363:
11343:
11326:
11306:
11269:
11206:formal
10966:
9872:&
9857:&
9839:&
9307:&
9237:forces
8998:Memory
8653:simple
7985:&
7967:&
7949:&
7020:&
7005:&
6987:&
6207:&
6180:&
5723:, and
5460:->
5451:&
5442:->
5355:valid.
5136:count
5110:&
5089:&
5071:&
5029:&
5014:&
4996:&
4981:start
4888:) | (
4868:) | (
4848:) | (
4828:) | (
4818:| ( ¬
4622:&
4060:&
3886:, and
3235:format
3231:models
1940:&
1913:&
1869:&
1722:TRUTH.
1693:) " ≡
1403:Jevons
1206:(b|a)
1143:NOT a
1140:NOT b
757:analog
657:atomic
331:syntax
12973:Model
12721:Peano
12578:Proof
12418:Arity
12347:Naive
12234:image
12166:Fuzzy
12126:Empty
12075:union
12020:Class
11661:Model
11651:Lemma
11609:Axiom
11529:Nicod
11158:and (
10970:pbk.)
10735:XOR b
10731:( ( a
10712:and b
6154:rows
6130:taut
6070:c → b
5345:valid
4598:taut
4374:(NOT)
4362:(AND)
4359:&
3983:taut
3129:Some
3060:v(B)
3054:v(A)
2962:) = F
2876:is a
1496:~(a)
1493:~(b)
1473:NAND
1401:from
1395:Boole
1393:from
1155:b IS
735:and "
667:, or
167:there
150:below
110:that
13096:Type
12899:list
12703:list
12680:list
12669:Term
12603:rank
12497:open
12391:list
12203:Maps
12108:sets
11967:Free
11937:list
11687:list
11614:list
11513:and
11499:ISBN
11479:ISBN
11448:ISBN
11428:ISBN
11379:ISBN
11361:ISBN
11341:ISBN
11324:ISBN
11304:ISBN
11294:and
11267:ISBN
10964:ISBN
10944:"u".
10907:and
10743:)= Σ
10706:bits
10689:and
9818:row
9328:= q
9110:= q
8885:= q
8765:= q
7925:row
6963:row
6597:and
6500:6,7
6417:4,5
6334:2,3
6251:0,1
5413:arg
5319:both
4906:>
4900:<
4896:>
4890:<
4886:>
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4816:>
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4804:>
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4466:and
4368:(OR)
3742:and
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3001:mean
2907:) ≠
2868:and
1952:=d2
1899:=d1
1837:row
1682:') ≡
1654:and
1479:XOR
1476:NOR
1467:AND
1464:NOT
1461:NOT
1385:and
887:and
737:blue
727:blue
418:row
190:The
118:, a
66:and
43:, a
23:, a
12783:of
12765:of
12713:of
12245:Sur
12219:Map
12026:Ur-
12008:Set
11142:of
10749:( a
10589:'s
9899:=q
8864:qd
6724:or
6688:cba
5323:and
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4807:::=
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4778:or
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3310:)))
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2890:, p
2886:, p
2845:, p
2841:, p
1812:d2
1775:d1
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1470:OR
98:In
90:OR
19:In
13328::
13169:NP
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12787::
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12249:Bi
12241:In
11162:-
11043:Df
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10585:,
10574:.
10515:1
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10101:1
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10085:1
10082:0
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10072:0
10069:1
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10063:2
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10000:1
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9890:)
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9884:)
9881:d
9878:(
9875:~
9869:c
9866:(
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9860:~
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9845:)
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9836:c
9833:(
9830:(
9827:c
9824:d
9821:q
9795:u
9792:r
9783:v
9780:w
9773:q
9766:s
9700:1
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9686:0
9683:0
9680:1
9675:1
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9667:1
9664:1
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9633:1
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9625:1
9620:0
9617:1
9614:1
9598:1
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9521:1
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9500:0
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9098:s
9095:(
9092:s
9089:p
9076:q
9037:.
8988:0
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8978:0
8973:1
8970:1
8962:1
8957:0
8952:1
8947:0
8944:1
8936:0
8931:1
8926:0
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8918:0
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8870:(
8867:p
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