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Three-valued logic

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390:; the addition of a third value in ternary logic leads to a total of 3 = 27 distinct operators on a single input value. (This may be made clear by considering all possible truth tables for an arbitrary unary operator. Given 2 possible values TF of the single Boolean input, there are four different patterns of output TT, TF, FT, FF resulting from the following unary operators acting on each value: always T, Identity, NOT, always F. Given three possible values of a ternary variable, each times three possible results of a unary operation, there are 27 different output patterns: TTT, TTU, TTF, TUT, TUU, TUF, TFT, TFU, TFF, UTT, UTU, UTF, UUT, UUU, UUF, UFT, UFU, UFF, FTT, FTU, FTF, FUT, FUU, FUF, FFT, FFU, and FFF.) Similarly, where Boolean logic has 2 = 16 distinct binary operators (operators with 2 inputs) possible, ternary logic has 3 = 19,683 such operators. Where the nontrival Boolean operators can be named ( 3001:
each on a subset of the natural numbers (as occurs e.g. after completing the definitions of any two partial recursive predicates classically). Let t, f, u mean 'decidable by the algorithms (i.e. by use of only such information about Q(x) and R(x) as can be obtained by the algorithms) to be true', 'decidable by the algorithms to be false', 'undecidable by the algorithms whether true or false'. (iv) Assume a fixed state of knowledge about Q(x) and R(x) (as occurs e.g. after pursuing algorithms for each of them up to a given stage). Let t, f, u mean 'known to be true', 'known to be false', 'unknown whether true or false'.
219:. He never published it. In fact, he did not even number the three pages of notes where he defined his three-valued operators. Peirce soundly rejected the idea all propositions must be either true or false; boundary-propositions, he writes, are "at the limit between P and not P." However, as confident as he was that "Triadic Logic is universally true," he also jotted down that "All this is mighty close to nonsense." Only in 1966, when Max Fisch and Atwell Turquette began publishing what they rediscovered in his unpublished manuscripts, did Peirce's triadic ideas become widely known. 5305: 245:
observational data that a statement as to the position of a motor car can never be falsified or verified, then there may be some point to not regarding the statement as true or false, but regarding it as "middle." It is only because, in macrocosmic experience, everything that we regard as an empirically meaningful statement seems to be at least potentially verifiable or falsifiable that we prefer the convention according to which we say that every such statement is either true or false, but in many cases we don't know which.
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However, it is not the case that 'middle' means "neither verified nor falsified at the present time." As we have seen, 'verified' and 'falsified' are epistemic predicates--that is to say, they are relative to the evidence at a particular time--whereas 'middle,' like 'true' and 'false' is not relative
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truth value for Kleene logic is True.) However, the lack of valid formulas does not mean that it lacks valid arguments and/or inference rules. An argument is semantically valid in Kleene logic if, whenever (for any interpretation/model) all of its premises are True, the conclusion must also be True.
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The strong 3-valued logic can be applied to completely defined predicates Q(x) and R(x), from which composite predicates are formed using ̅, V, &, ->, ≡ in the usual 2-valued meanings, thus, (iii) Suppose that there are fixed algorithms which decide the truth or falsity of Q(x) and of R(x),
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But there is a second possible way to conceive of many-valued logics: that while a proposition, in itself, can have only two values, true or false, that is to say two responses, yes or no, it may happen that a given individual does not know the response, at least at a given moment; therefore, for
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state can be thought of as neither true nor false in Kleene logic, or thought of as both true and false in Priest logic. The difference lies in the definition of tautologies. Where Kleene logic's only designated truth value is T, Priest logic's designated truth values are both T and U. In Kleene
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For example, if we have verified (by using a speedometer) that the velocity of a motor car is such and such, it might be impossible in such a world to verify or falsify certain statements concerning its position at that moment. If we know by reference to a physical law together with certain
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or inequality), with six trivial operators considering 0 or 1 inputs only, it is unreasonable to attempt to name all but a small fraction of the possible ternary operators. Just as in bivalent logic, where not all operators are given names and subsets of
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Broadly speaking, the primary motivation for research of three valued logic is to represent the truth value of a statement that cannot be represented as true or false. Łukasiewicz initially developed three valued logic for the
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Kleene logic has no tautologies (valid formulas) because whenever all of the atomic components of a well-formed formula are assigned the value Unknown, the formula itself must also have the value Unknown. (And the only
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is credited with first introducing additional logical truth degrees in his 1921 theory of elementary propositions. The conceptual form and basic ideas of three-valued logic were initially published by
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the individual there is a third attitude possible toward a proposition. This third attitude does not correspond to a distinct third value of yes or of no, but simply to a doubt between yes or no
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where the third truth value NF (not false) has the semantics of a proposition that can be intuitionistically proven to not be false, but does not have an intuitionistic proof of correctness.
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using a three-valued logic, "it is possible that..." L is read "it is true that..." or "it is necessary that..." Finally I is read "it is unknown that..." or "it is contingent that..."
1967: 1106: 2355:, or by explicit truth tables for its operations. In particular, conjunction and disjunction are the same as for Kleene's and Łukasiewicz's logic, while the negation is different. 1391:
The Łukasiewicz Ł3 has the same tables for AND, OR, and NOT as the Kleene logic given above, but differs in its definition of implication in that "unknown implies unknown" is
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truth values instead of one; these are: True and Both (the analogue of Unknown), so that LP does have tautologies but it has fewer valid inference rules).
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RM3 is a non-cartesian symmetric monoidal closed category; the product, which is left-adjoint to the implication, lacks valid projections, and has
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in the lattice of intermediate logics. In this sense it may be viewed as the "second strongest" intermediate logic after classical logic.
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Cobreros, Pablo; Égré, Paul; Ripley, David; Rooij, Robert van (2 January 2014). "Foreword: Three-valued logics and their applications".
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Mundici, D. The C*-Algebras of Three-Valued Logic. Logic Colloquium ’88, Proceedings of the Colloquium held in Padova 61–77 (1989).
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at any moment in time is not available. However, certain logical operations can yield an unambiguous result, even if they involve an
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are tautologies in Ł3 and also in classical logic. Not all tautologies of classical logic lift to Ł3 "as is". For example, the
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As with bivalent logic, truth values in ternary logic may be represented numerically using various representations of the
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used a third value to represent when "a given individual does not know the response, at least at a given moment."
2583: 4312: 4005: 281: 3746: 1190:{\displaystyle A\rightarrow B\ {\overset {\underset {\mathrm {def} }{}}{=}}\ {\mbox{OR}}(\ {\mbox{NOT}}(A),\ B)} 5268: 4970: 4733: 4728: 4553: 3974: 3658: 254: 57: 46: 5263: 5046: 4963: 4676: 4607: 4484: 3726: 2498: 277:, each digit has one of 3 values: −1, 0, or +1; these values may also be simplified to −, 0, +, respectively; 229: 2133: 5188: 5014: 4700: 4334: 3933: 3276: 5066: 5061: 4671: 4410: 4339: 3668: 3569: 3437: 2503: 2473:
field content. SQL uses a common fragment of the Kleene K3 logic, restricted to AND, OR, and NOT tables.
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M is read as "it is not false that..." or in the (unsuccessful) Tarski–Łukasiewicz attempt to axiomatize
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In fact, using Łukasiewicz's implication and negation, the other usual connectives may be derived as:
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have been introduced more recently, motivated by circuit problems rather than philosophical issues:
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It is also possible to derive a few other useful unary operators (first derived by Tarski in 1921):
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Rybaříková, Zuzana (1 May 2021). "Łukasiewicz, determinism, and the four-valued system of logic".
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An Introduction to Many-Valued and Fuzzy Logic: Semantics, Algebras, and Derivation Systems
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Handbook of the History of Logic Volume 8. The Many Valued and Nonmonotonic Turn in Logic
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operators are used, there may be functionally complete sets of ternary-valued operators.
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is True, meaning that only a proposition having this value everywhere is considered a
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as well. In this example, because either bivalent state could be underlying the
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using the truth values {false, unknown, true}, and extends conventional Boolean
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de Finetti, Bruno (1 January 1995). "The logic of probability (translated)".
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defined above, it is possible to state tautologies that are their analogues:
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Triadic Logic is universally true. But Dyadic Logic is not aboslutely false
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to represent the truth value of statements about the undetermined future.
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which, by adjointness, is equivalent to the projection from the product:
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This logic is also known as a weak form of Kleene's three-valued logic.
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A defining characteristic of RM3 is the lack of the axiom of Weakening:
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It may be defined either by appending one of the two equivalent axioms
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Paraconsistent logic § An ideal three-valued paraconsistent logic
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Heyting (1930). "Die formalen Regeln der intuitionistischen Logik".
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hollisarchives.lib.harvard.edu/repositories/24/digital_objects/63983
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hollisarchives.lib.harvard.edu/repositories/24/digital_objects/63983
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The truth table for the material implication of R-mingle 3 (RM3) is
24: 5275: 5073: 4521: 4226: 3820: 3052: 2536:– an experimental Russian computer which was based on ternary logic 3094:. London, England: Penguin Books. Entry for 'three-valued logic'. 2147: 4871: 3663: 3505: 3020:. Reading, Mass.: Addison-Wesley Publishing Company. p. 190. 2469:
implements ternary logic as a means of handling comparisons with
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which differs from that for Łukasiewicz logic (described below).
1373:(LP) has the same truth tables as Kleene logic, but it has two 240:
used it to represent values that cannot physically be decided:
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Many-valued logic § Bochvar's internal three-valued logic
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that are "undecidable by algorithms whether true or false"
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not(a) = (a + 1) mod (n), where (n) is the value of a logic
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Material implication for Łukasiewicz logic truth table is
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Material implication for Kleene logic can be defined as:
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Putnam, Hilary (1 October 1957). "Three-valued logic".
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as the monoid identity. This logic is equivalent to an
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are not tautologies in Ł3. However, using the operator
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The Penguin Dictionary of Mathematics. Fourth Edition
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state, and either state also yields the same result,
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in an axiomatic algebraic form, and also extended to
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This article mainly illustrates a system of ternary
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Multiple valued logic: concepts and representations
49:. Unsourced material may be challenged and removed. 3171:Miller, D. Michael; Thornton, Mitchell A. (2008). 1189: 5321: 3197:Multiple-Valued Logic Synthesis and Optimization 947: 874: 801: 676: 603: 530: 2134:Many-valued logic § Gödel logics Gk and G∞ 1003:logic, the knowledge of whether any particular 3258:. University of California Press. Dover 1998: 3170: 301:(trinary digit) having a value of: 0, 1, or 2; 3577: 3284: 3256:Philosophic Foundations of Quantum Mechanics 3055:, the Scientific Research Society: 490–494. 2829:"Three-Valued Logic and Future Contingents" 2742: 2712: 430: 260: 3769: 3584: 3570: 3291: 3277: 2931: 2925: 2904: 2898: 2795: 2793: 2791: 269:. A few of the more common examples are: 2650: 2632: 2622: 109:Learn how and when to remove this message 3215: 3203:, Kluwer Academic Publishers, pp. 89-114 169:logics (such as classical sentential or 3298: 3199:, in Hassoun S. and Sasao T., editors, 3155: 2802:Journal of Applied Non-Classical Logics 2788: 449:'s "strong logic of indeterminacy" and 16:System including an indeterminate value 5322: 3591: 3142:" in Dov M. Gabbay, John Woods (eds.) 3087: 3018:The Art of Computer Programming Vol. 2 2993: 2987: 2962: 2956: 2865: 2859: 2751:. Houghton Library, Harvard University 2721:. Houghton Library, Harvard University 1706:They have the following truth tables: 3565: 3272: 3030: 3012: 2868:"The Problem of Future Contingencies" 2826: 2413: 2234: 2118:which also obeys the contrapositive. 1995: 1495: 1418: 1290: 1213: 928: 855: 782: 657: 584: 511: 3140:Many-valued Logic and its Philosophy 2820: 2689: 2604: 2378: 2284: 2045: 1545: 1468: 1380: 1340: 1263: 950: 877: 804: 679: 606: 533: 360:, ternary values are represented by 47:adding citations to reliable sources 18: 2833:The Philosophical Quarterly (1950-) 2426: 2168:(F, false; NF, not false; T, true) 195:. These were then re-formulated by 13: 3209: 2142:, also referred as Smetanov logic 1136: 1133: 1130: 730:(−1, false; 0, unknown; +1, true) 14: 5346: 2702:from the original on Dec 6, 2023. 2594:from the original on May 3, 2023. 445:showing the logic operations for 153:systems in which there are three 5303: 3201:Logic Synthesis and Verification 2776:www.digitalpeirce.fee.unicamp.br 2769: 2743:Peirce, Charles S. (1839–1914). 2713:Peirce, Charles S. (1839–1914). 2584:"Trilean (Stanford JavaNLP API)" 2483: 2382: 2365: 2154:in 1930 as a model for studying 1968:extended contradiction principle 1397:Handbook of the History of Logic 459:(F, false; U, unknown; T, true) 437:Kleene algebra (with involution) 253:used a third value to represent 206: 23: 3189: 3164: 3149: 3132: 3121: 3108: 3081: 3070:from the original on 2019-10-30 3024: 3006: 2996:Introduction to metamathematics 2611:American Journal of Mathematics 2449: 2220: 2164: 1981: 1708: 1404: 1199: 924:MIN(MAX(A, B), NEG(MIN(A, B))) 726: 455: 282:redundant binary representation 34:needs additional citations for 3222:. Cambridge University Press. 2763: 2736: 2706: 2683: 2659: 2634:2027/uiuo.ark:/13960/t9j450f7q 2598: 2576: 1184: 1172: 1166: 1153: 1113: 1019:operand. For example, because 1: 5264:History of mathematical logic 3250:10.1016/s0049-237x(08)70262-3 2994:Kleene, Stephen Cole (1952). 2570: 2499:Binary logic (disambiguation) 2222: 2171: 2138:The logic of here and there ( 1983: 1710: 1406: 1201: 733: 462: 230:problem of future contingents 222: 5189:Primitive recursive function 3128:"Beyond Propositional Logic" 2814:10.1080/11663081.2014.909631 2465:The database query language 2116:"ideal" paraconsistent logic 1974: 1063:results in all three cases. 7: 3438:Ontology (computer science) 2504:Boolean algebra (structure) 2476: 2121: 998:In these truth tables, the 10: 5351: 4253:Schröder–Bernstein theorem 3980:Monadic predicate calculus 3639:Foundations of mathematics 3331:Intuitionistic type theory 3254:Reichenbach, Hans (1944). 3034:(November–December 2001). 2458: 2419:not(a) = (a + 1) mod 3, or 2369: 2131: 2125: 1384: 1007:state secretly represents 434: 5299: 5286:Philosophy of mathematics 5235:Automated theorem proving 5217: 5112: 4944: 4837: 4689: 4406: 4382: 4360:Von Neumann–Bernays–Gödel 4305: 4199: 4103: 4001: 3992: 3919: 3854: 3760: 3682: 3599: 3528: 3479: 3451: 3428: 3410: 3382: 3344: 3306: 3216:Bergmann, Merrie (2008). 2524:Homogeneity (linguistics) 2445:Dubrova and Muzio algebra 2270: 2256: 2253: 2237: 2207: 2199: 2191: 2167: 2150:G3 logic), introduced by 2031: 2017: 2014: 1998: 1836: 1828: 1820: 1791: 1783: 1775: 1746: 1738: 1730: 1531: 1517: 1514: 1498: 1454: 1440: 1437: 1421: 1326: 1312: 1309: 1293: 1249: 1235: 1232: 1216: 1197:, and its truth table is 978: 964: 931: 905: 891: 858: 832: 818: 785: 765: 757: 749: 729: 707: 693: 660: 634: 620: 587: 561: 547: 514: 494: 486: 478: 458: 378: 306:skew binary number system 197:Grigore Constantin Moisil 173:) which provide only for 2872:The Philosophical Review 2866:Taylor, Richard (1957). 2248: 2245: 2242: 2186: 2183: 2009: 2006: 2003: 1901:law of non-contradiction 1857:In Łukasiewicz's Ł3 the 1810: 1805: 1765: 1760: 1720: 1715: 1509: 1506: 1503: 1432: 1429: 1426: 1304: 1301: 1298: 1227: 1224: 1221: 1070:values, are assigned to 1066:If numeric values, e.g. 942: 939: 936: 869: 866: 863: 796: 793: 790: 744: 741: 671: 668: 665: 598: 595: 592: 525: 522: 519: 473: 470: 431:Kleene and Priest logics 375:to a trivalent context. 261:Representation of values 217:many-valued logic system 203:-valued logics in 1945. 145:, sometimes abbreviated 4936:Self-verifying theories 4757:Tarski's axiomatization 3708:Tarski's undefinability 3703:incompleteness theorems 3336:Constructive set theory 3195:Dubrova, Elena (2002). 2358:HT logic is the unique 453:'s "logic of paradox". 5310:Mathematics portal 4921:Proof of impossibility 4569:propositional variable 3879:Propositional calculus 3138:Grzegorz Malinowski, " 3116:Standard Ternary Logic 3088:Nelson, David (2008). 2605:Post, Emil L. (1921). 2590:. Stanford NLP Group. 2545:Ternary numeral system 2454: 2391:This section is empty. 1943:law of excluded fourth 1887:law of excluded middle 1491:(A, B), MIN(1, 1−A+B) 1191: 289:ternary numeral system 267:ternary numeral system 247: 213:Charles Sanders Peirce 5179:Kolmogorov complexity 5132:Computably enumerable 5032:Model complete theory 4824:Principia Mathematica 3884:Propositional formula 3713:Banach–Tarski paradox 3321:Constructive analysis 2965:Philosophical Studies 2934:Philosophical Studies 2919:10.1515/sem-2019-0115 2827:Prior, A. N. (1953). 2132:Further information: 2126:Further information: 1385:Further information: 1192: 425:functionally complete 418:), and 4 variants of 242: 193:Clarence Irving Lewis 5127:Church–Turing thesis 5114:Computability theory 4323:continuum hypothesis 3841:Square of opposition 3699:Gödel's completeness 3374:Fuzzy set operations 3369:Fuzzy finite element 3316:Intuitionistic logic 3061:10.1511/2001.40.3268 2433:modulars arithmetics 2353:intuitionistic logic 2158:, is a three-valued 2156:intuitionistic logic 1107: 149:) is any of several 58:"Three-valued logic" 43:improve this article 5281:Mathematical object 5172:P versus NP problem 5137:Computable function 4931:Reverse mathematics 4857:Logical consequence 4734:primitive recursive 4729:elementary function 4502:Free/bound variable 4355:Tarski–Grothendieck 3874:Logical connectives 3804:Logical equivalence 3654:Logical consequence 3551:Non-monotonic logic 3300:Non-classical logic 2588:Stanford University 2565:The World of Null-A 2540:Strawson entailment 2231: 2180: 1992: 1492: 1415: 1287: 1286:(A, B), MAX(−A, B) 1210: 925: 852: 779: 738: 654: 581: 508: 467: 447:Stephen Cole Kleene 369:propositional logic 251:Stephen Cole Kleene 5079:Transfer principle 5042:Semantics of logic 5027:Categorical theory 5003:Non-standard model 4517:Logical connective 3644:Information theory 3593:Mathematical logic 3546:Intermediate logic 3326:Heyting arithmetic 3114:Douglas W. Jones, 3044:American Scientist 2977:10.1007/BF02304905 2946:10.1007/BF00996317 2671:plato.stanford.edu 2414:Ternary Post logic 2225: 2174: 2160:intermediate logic 2128:Intermediate logic 1986: 1486: 1409: 1281: 1209:(A, B), OR(¬A, B) 1204: 1187: 1164: 1151: 1140: 923: 850: 777: 736: 652: 579: 506: 465: 441:Below is a set of 127:three-valued logic 5335:Ternary computers 5330:Many-valued logic 5317: 5316: 5249:Abstract category 5052:Theories of truth 4862:Rule of inference 4852:Natural deduction 4833: 4832: 4378: 4377: 4083:Cartesian product 3988: 3987: 3894:Many-valued logic 3869:Boolean functions 3752:Russell's paradox 3727:diagonal argument 3624:First-order logic 3559: 3558: 3541:Inquisitive logic 3536:Dynamic semantics 3489:Three-state logic 3443:Ontology language 3229:978-0-521-88128-9 3182:978-1-59829-190-2 2690:Lane, R. (2001). 2555:Three-state logic 2519:Four-valued logic 2491:Philosophy portal 2411: 2410: 2351:to the axioms of 2302: 2301: 2298: 2297: 2219: 2218: 2215: 2214: 2063: 2062: 2059: 2058: 1848: 1847: 1844: 1843: 1799: 1798: 1754: 1753: 1563: 1562: 1559: 1558: 1482: 1481: 1387:Łukasiewicz logic 1381:Łukasiewicz logic 1358: 1357: 1354: 1353: 1277: 1276: 1180: 1163: 1158: 1150: 1145: 1141: 1128: 1127: 1121: 996: 995: 992: 991: 919: 918: 846: 845: 773: 772: 725: 724: 721: 720: 648: 647: 575: 574: 502: 501: 151:many-valued logic 119: 118: 111: 93: 5342: 5308: 5307: 5259:History of logic 5254:Category of sets 5147:Decision problem 4926:Ordinal analysis 4867:Sequent calculus 4765:Boolean algebras 4705: 4704: 4679: 4650:logical/constant 4404: 4403: 4390: 4313:Zermelo–Fraenkel 4064:Set operations: 3999: 3998: 3936: 3767: 3766: 3747:Löwenheim–Skolem 3634:Formal semantics 3586: 3579: 3572: 3563: 3562: 3494:Tri-state buffer 3293: 3286: 3279: 3270: 3269: 3240: 3238: 3236: 3204: 3193: 3187: 3186: 3168: 3162: 3161: 3153: 3147: 3146:, Elsevier, 2009 3136: 3130: 3125: 3119: 3118:, Feb. 11, 2013. 3112: 3106: 3105: 3085: 3079: 3078: 3076: 3075: 3069: 3040: 3028: 3022: 3021: 3014:Knuth, Donald E. 3010: 3004: 3003: 2991: 2985: 2984: 2982:to the evidence. 2960: 2954: 2953: 2929: 2923: 2922: 2913:(240): 129–143. 2902: 2896: 2895: 2863: 2857: 2856: 2824: 2818: 2817: 2797: 2786: 2785: 2783: 2782: 2767: 2761: 2760: 2758: 2756: 2740: 2734: 2733: 2728: 2726: 2710: 2704: 2703: 2687: 2681: 2680: 2678: 2677: 2663: 2657: 2656: 2654: 2636: 2626: 2602: 2596: 2595: 2580: 2559:tri-state buffer 2549:Balanced ternary 2509:Boolean function 2493: 2488: 2487: 2486: 2427:Modular algebras 2406: 2403: 2393:You can help by 2386: 2379: 2350: 2332:or equivalently 2331: 2232: 2224: 2221: 2181: 2173: 2165: 2113: 2104: 2083: 1993: 1985: 1982: 1965: 1940: 1920: 1914: 1898: 1884: 1874: 1859:designated value 1816: 1808: 1803: 1802: 1771: 1763: 1758: 1757: 1726: 1718: 1713: 1712: 1709: 1702: 1678: 1660: 1637: 1609: 1589: 1493: 1485: 1416: 1408: 1405: 1371:Logic of Paradox 1288: 1280: 1211: 1203: 1200: 1196: 1194: 1193: 1188: 1178: 1165: 1161: 1156: 1152: 1148: 1143: 1142: 1139: 1123: 1119: 1068:balanced ternary 926: 922: 853: 849: 780: 776: 739: 735: 727: 655: 651: 582: 578: 509: 505: 468: 464: 456: 358:ternary computer 275:balanced ternary 234:Bruno de Finetti 114: 107: 103: 100: 94: 92: 51: 27: 19: 5350: 5349: 5345: 5344: 5343: 5341: 5340: 5339: 5320: 5319: 5318: 5313: 5302: 5295: 5240:Category theory 5230:Algebraic logic 5213: 5184:Lambda calculus 5122:Church encoding 5108: 5084:Truth predicate 4940: 4906:Complete theory 4829: 4698: 4694: 4690: 4685: 4677: 4397: and  4393: 4388: 4374: 4350:New Foundations 4318:axiom of choice 4301: 4263:Gödel numbering 4203: and  4195: 4099: 3984: 3934: 3915: 3864:Boolean algebra 3850: 3814:Equiconsistency 3779:Classical logic 3756: 3737:Halting problem 3725: and  3701: and  3689: and  3688: 3683:Theorems ( 3678: 3595: 3590: 3560: 3555: 3524: 3475: 3447: 3424: 3406: 3397:Relevance logic 3392:Structural rule 3378: 3354:Degree of truth 3340: 3302: 3297: 3234: 3232: 3230: 3212: 3210:Further reading 3207: 3194: 3190: 3183: 3169: 3165: 3154: 3150: 3137: 3133: 3126: 3122: 3113: 3109: 3102: 3086: 3082: 3073: 3071: 3067: 3038: 3029: 3025: 3011: 3007: 2992: 2988: 2961: 2957: 2930: 2926: 2903: 2899: 2884:10.2307/2182851 2864: 2860: 2845:10.2307/2217099 2839:(13): 317–326. 2825: 2821: 2798: 2789: 2780: 2778: 2772:"Triadic Logic" 2768: 2764: 2754: 2752: 2741: 2737: 2724: 2722: 2711: 2707: 2692:"Triadic Logic" 2688: 2684: 2675: 2673: 2665: 2664: 2660: 2624:10.2307/2370324 2603: 2599: 2582: 2581: 2577: 2573: 2514:Digital circuit 2489: 2484: 2482: 2479: 2463: 2457: 2452: 2442:Pradhan algebra 2429: 2416: 2407: 2401: 2398: 2374: 2368: 2333: 2305: 2229: 2178: 2136: 2130: 2124: 2109: 2091: 2069: 1990: 1977: 1948: 1925: 1916: 1904: 1890: 1876: 1866: 1865:. For example, 1811: 1806: 1766: 1761: 1721: 1716: 1681: 1663: 1645: 1612: 1592: 1569: 1490: 1413: 1389: 1383: 1285: 1208: 1159: 1146: 1129: 1122: 1108: 1105: 1104: 439: 433: 388:unary operators 381: 362:ternary signals 263: 225: 209: 189:Jan Łukasiewicz 115: 104: 98: 95: 52: 50: 40: 28: 17: 12: 11: 5: 5348: 5338: 5337: 5332: 5315: 5314: 5300: 5297: 5296: 5294: 5293: 5288: 5283: 5278: 5273: 5272: 5271: 5261: 5256: 5251: 5242: 5237: 5232: 5227: 5225:Abstract logic 5221: 5219: 5215: 5214: 5212: 5211: 5206: 5204:Turing machine 5201: 5196: 5191: 5186: 5181: 5176: 5175: 5174: 5169: 5164: 5159: 5154: 5144: 5142:Computable set 5139: 5134: 5129: 5124: 5118: 5116: 5110: 5109: 5107: 5106: 5101: 5096: 5091: 5086: 5081: 5076: 5071: 5070: 5069: 5064: 5059: 5049: 5044: 5039: 5037:Satisfiability 5034: 5029: 5024: 5023: 5022: 5012: 5011: 5010: 5000: 4999: 4998: 4993: 4988: 4983: 4978: 4968: 4967: 4966: 4961: 4954:Interpretation 4950: 4948: 4942: 4941: 4939: 4938: 4933: 4928: 4923: 4918: 4908: 4903: 4902: 4901: 4900: 4899: 4889: 4884: 4874: 4869: 4864: 4859: 4854: 4849: 4843: 4841: 4835: 4834: 4831: 4830: 4828: 4827: 4819: 4818: 4817: 4816: 4811: 4810: 4809: 4804: 4799: 4779: 4778: 4777: 4775:minimal axioms 4772: 4761: 4760: 4759: 4748: 4747: 4746: 4741: 4736: 4731: 4726: 4721: 4708: 4706: 4687: 4686: 4684: 4683: 4682: 4681: 4669: 4664: 4663: 4662: 4657: 4652: 4647: 4637: 4632: 4627: 4622: 4621: 4620: 4615: 4605: 4604: 4603: 4598: 4593: 4588: 4578: 4573: 4572: 4571: 4566: 4561: 4551: 4550: 4549: 4544: 4539: 4534: 4529: 4524: 4514: 4509: 4504: 4499: 4498: 4497: 4492: 4487: 4482: 4472: 4467: 4465:Formation rule 4462: 4457: 4456: 4455: 4450: 4440: 4439: 4438: 4428: 4423: 4418: 4413: 4407: 4401: 4384:Formal systems 4380: 4379: 4376: 4375: 4373: 4372: 4367: 4362: 4357: 4352: 4347: 4342: 4337: 4332: 4327: 4326: 4325: 4320: 4309: 4307: 4303: 4302: 4300: 4299: 4298: 4297: 4287: 4282: 4281: 4280: 4273:Large cardinal 4270: 4265: 4260: 4255: 4250: 4236: 4235: 4234: 4229: 4224: 4209: 4207: 4197: 4196: 4194: 4193: 4192: 4191: 4186: 4181: 4171: 4166: 4161: 4156: 4151: 4146: 4141: 4136: 4131: 4126: 4121: 4116: 4110: 4108: 4101: 4100: 4098: 4097: 4096: 4095: 4090: 4085: 4080: 4075: 4070: 4062: 4061: 4060: 4055: 4045: 4040: 4038:Extensionality 4035: 4033:Ordinal number 4030: 4020: 4015: 4014: 4013: 4002: 3996: 3990: 3989: 3986: 3985: 3983: 3982: 3977: 3972: 3967: 3962: 3957: 3952: 3951: 3950: 3940: 3939: 3938: 3925: 3923: 3917: 3916: 3914: 3913: 3912: 3911: 3906: 3901: 3891: 3886: 3881: 3876: 3871: 3866: 3860: 3858: 3852: 3851: 3849: 3848: 3843: 3838: 3833: 3828: 3823: 3818: 3817: 3816: 3806: 3801: 3796: 3791: 3786: 3781: 3775: 3773: 3764: 3758: 3757: 3755: 3754: 3749: 3744: 3739: 3734: 3729: 3717:Cantor's  3715: 3710: 3705: 3695: 3693: 3680: 3679: 3677: 3676: 3671: 3666: 3661: 3656: 3651: 3646: 3641: 3636: 3631: 3626: 3621: 3616: 3615: 3614: 3603: 3601: 3597: 3596: 3589: 3588: 3581: 3574: 3566: 3557: 3556: 3554: 3553: 3548: 3543: 3538: 3532: 3530: 3526: 3525: 3523: 3522: 3521: 3520: 3510: 3509: 3508: 3498: 3497: 3496: 3485: 3483: 3477: 3476: 3474: 3473: 3468: 3463: 3457: 3455: 3449: 3448: 3446: 3445: 3440: 3434: 3432: 3426: 3425: 3423: 3422: 3416: 3414: 3412:Paraconsistent 3408: 3407: 3405: 3404: 3399: 3394: 3388: 3386: 3380: 3379: 3377: 3376: 3371: 3366: 3361: 3356: 3350: 3348: 3342: 3341: 3339: 3338: 3333: 3328: 3323: 3318: 3312: 3310: 3308:Intuitionistic 3304: 3303: 3296: 3295: 3288: 3281: 3273: 3267: 3266: 3252: 3242: 3241:, chapters 5-9 3228: 3211: 3208: 3206: 3205: 3188: 3181: 3163: 3148: 3131: 3120: 3107: 3100: 3080: 3023: 3005: 2986: 2955: 2940:(1): 181–190. 2924: 2897: 2858: 2819: 2787: 2770:Lane, Robert. 2762: 2735: 2705: 2682: 2658: 2617:(3): 163–185. 2597: 2574: 2572: 2569: 2568: 2567: 2562: 2552: 2542: 2537: 2531: 2526: 2521: 2516: 2511: 2506: 2501: 2495: 2494: 2478: 2475: 2459:Main article: 2456: 2453: 2451: 2448: 2447: 2446: 2443: 2440: 2428: 2425: 2424: 2423: 2420: 2415: 2412: 2409: 2408: 2389: 2387: 2370:Main article: 2367: 2364: 2300: 2299: 2296: 2295: 2292: 2289: 2286: 2282: 2281: 2278: 2275: 2272: 2268: 2267: 2264: 2261: 2258: 2255: 2251: 2250: 2247: 2244: 2240: 2239: 2236: 2227: 2217: 2216: 2213: 2212: 2209: 2205: 2204: 2201: 2197: 2196: 2193: 2189: 2188: 2185: 2176: 2170: 2169: 2123: 2120: 2106: 2105: 2085: 2084: 2061: 2060: 2057: 2056: 2053: 2050: 2047: 2043: 2042: 2039: 2036: 2033: 2029: 2028: 2025: 2022: 2019: 2016: 2012: 2011: 2008: 2005: 2001: 2000: 1997: 1988: 1976: 1973: 1972: 1971: 1946: 1846: 1845: 1842: 1841: 1838: 1834: 1833: 1830: 1826: 1825: 1822: 1818: 1817: 1809: 1800: 1797: 1796: 1793: 1789: 1788: 1785: 1781: 1780: 1777: 1773: 1772: 1764: 1755: 1752: 1751: 1748: 1744: 1743: 1740: 1736: 1735: 1732: 1728: 1727: 1719: 1704: 1703: 1679: 1661: 1639: 1638: 1610: 1590: 1561: 1560: 1557: 1556: 1553: 1550: 1547: 1543: 1542: 1539: 1536: 1533: 1529: 1528: 1525: 1522: 1519: 1516: 1512: 1511: 1508: 1505: 1501: 1500: 1497: 1488: 1483: 1480: 1479: 1476: 1473: 1470: 1466: 1465: 1462: 1459: 1456: 1452: 1451: 1448: 1445: 1442: 1439: 1435: 1434: 1431: 1428: 1424: 1423: 1420: 1411: 1382: 1379: 1356: 1355: 1352: 1351: 1348: 1345: 1342: 1338: 1337: 1334: 1331: 1328: 1324: 1323: 1320: 1317: 1314: 1311: 1307: 1306: 1303: 1300: 1296: 1295: 1292: 1283: 1278: 1275: 1274: 1271: 1268: 1265: 1261: 1260: 1257: 1254: 1251: 1247: 1246: 1243: 1240: 1237: 1234: 1230: 1229: 1226: 1223: 1219: 1218: 1215: 1206: 1186: 1183: 1177: 1174: 1171: 1168: 1155: 1138: 1135: 1132: 1126: 1118: 1115: 1112: 994: 993: 990: 989: 986: 983: 980: 976: 975: 972: 969: 966: 962: 961: 958: 955: 952: 949: 945: 944: 941: 938: 934: 933: 930: 920: 917: 916: 913: 910: 907: 903: 902: 899: 896: 893: 889: 888: 885: 882: 879: 876: 872: 871: 868: 865: 861: 860: 857: 847: 844: 843: 840: 837: 834: 830: 829: 826: 823: 820: 816: 815: 812: 809: 806: 803: 799: 798: 795: 792: 788: 787: 784: 774: 771: 770: 767: 763: 762: 759: 755: 754: 751: 747: 746: 743: 732: 731: 723: 722: 719: 718: 715: 712: 709: 705: 704: 701: 698: 695: 691: 690: 687: 684: 681: 678: 674: 673: 670: 667: 663: 662: 659: 649: 646: 645: 642: 639: 636: 632: 631: 628: 625: 622: 618: 617: 614: 611: 608: 605: 601: 600: 597: 594: 590: 589: 586: 576: 573: 572: 569: 566: 563: 559: 558: 555: 552: 549: 545: 544: 541: 538: 535: 532: 528: 527: 524: 521: 517: 516: 513: 503: 500: 499: 496: 492: 491: 488: 484: 483: 480: 476: 475: 472: 461: 460: 432: 429: 380: 377: 354: 353: 342: 309: 302: 285: 278: 262: 259: 224: 221: 208: 205: 185:Emil Leon Post 117: 116: 31: 29: 22: 15: 9: 6: 4: 3: 2: 5347: 5336: 5333: 5331: 5328: 5327: 5325: 5312: 5311: 5306: 5298: 5292: 5289: 5287: 5284: 5282: 5279: 5277: 5274: 5270: 5267: 5266: 5265: 5262: 5260: 5257: 5255: 5252: 5250: 5246: 5243: 5241: 5238: 5236: 5233: 5231: 5228: 5226: 5223: 5222: 5220: 5216: 5210: 5207: 5205: 5202: 5200: 5199:Recursive set 5197: 5195: 5192: 5190: 5187: 5185: 5182: 5180: 5177: 5173: 5170: 5168: 5165: 5163: 5160: 5158: 5155: 5153: 5150: 5149: 5148: 5145: 5143: 5140: 5138: 5135: 5133: 5130: 5128: 5125: 5123: 5120: 5119: 5117: 5115: 5111: 5105: 5102: 5100: 5097: 5095: 5092: 5090: 5087: 5085: 5082: 5080: 5077: 5075: 5072: 5068: 5065: 5063: 5060: 5058: 5055: 5054: 5053: 5050: 5048: 5045: 5043: 5040: 5038: 5035: 5033: 5030: 5028: 5025: 5021: 5018: 5017: 5016: 5013: 5009: 5008:of arithmetic 5006: 5005: 5004: 5001: 4997: 4994: 4992: 4989: 4987: 4984: 4982: 4979: 4977: 4974: 4973: 4972: 4969: 4965: 4962: 4960: 4957: 4956: 4955: 4952: 4951: 4949: 4947: 4943: 4937: 4934: 4932: 4929: 4927: 4924: 4922: 4919: 4916: 4915:from ZFC 4912: 4909: 4907: 4904: 4898: 4895: 4894: 4893: 4890: 4888: 4885: 4883: 4880: 4879: 4878: 4875: 4873: 4870: 4868: 4865: 4863: 4860: 4858: 4855: 4853: 4850: 4848: 4845: 4844: 4842: 4840: 4836: 4826: 4825: 4821: 4820: 4815: 4814:non-Euclidean 4812: 4808: 4805: 4803: 4800: 4798: 4797: 4793: 4792: 4790: 4787: 4786: 4784: 4780: 4776: 4773: 4771: 4768: 4767: 4766: 4762: 4758: 4755: 4754: 4753: 4749: 4745: 4742: 4740: 4737: 4735: 4732: 4730: 4727: 4725: 4722: 4720: 4717: 4716: 4714: 4710: 4709: 4707: 4702: 4696: 4691:Example  4688: 4680: 4675: 4674: 4673: 4670: 4668: 4665: 4661: 4658: 4656: 4653: 4651: 4648: 4646: 4643: 4642: 4641: 4638: 4636: 4633: 4631: 4628: 4626: 4623: 4619: 4616: 4614: 4611: 4610: 4609: 4606: 4602: 4599: 4597: 4594: 4592: 4589: 4587: 4584: 4583: 4582: 4579: 4577: 4574: 4570: 4567: 4565: 4562: 4560: 4557: 4556: 4555: 4552: 4548: 4545: 4543: 4540: 4538: 4535: 4533: 4530: 4528: 4525: 4523: 4520: 4519: 4518: 4515: 4513: 4510: 4508: 4505: 4503: 4500: 4496: 4493: 4491: 4488: 4486: 4483: 4481: 4478: 4477: 4476: 4473: 4471: 4468: 4466: 4463: 4461: 4458: 4454: 4451: 4449: 4448:by definition 4446: 4445: 4444: 4441: 4437: 4434: 4433: 4432: 4429: 4427: 4424: 4422: 4419: 4417: 4414: 4412: 4409: 4408: 4405: 4402: 4400: 4396: 4391: 4385: 4381: 4371: 4368: 4366: 4363: 4361: 4358: 4356: 4353: 4351: 4348: 4346: 4343: 4341: 4338: 4336: 4335:Kripke–Platek 4333: 4331: 4328: 4324: 4321: 4319: 4316: 4315: 4314: 4311: 4310: 4308: 4304: 4296: 4293: 4292: 4291: 4288: 4286: 4283: 4279: 4276: 4275: 4274: 4271: 4269: 4266: 4264: 4261: 4259: 4256: 4254: 4251: 4248: 4244: 4240: 4237: 4233: 4230: 4228: 4225: 4223: 4220: 4219: 4218: 4214: 4211: 4210: 4208: 4206: 4202: 4198: 4190: 4187: 4185: 4182: 4180: 4179:constructible 4177: 4176: 4175: 4172: 4170: 4167: 4165: 4162: 4160: 4157: 4155: 4152: 4150: 4147: 4145: 4142: 4140: 4137: 4135: 4132: 4130: 4127: 4125: 4122: 4120: 4117: 4115: 4112: 4111: 4109: 4107: 4102: 4094: 4091: 4089: 4086: 4084: 4081: 4079: 4076: 4074: 4071: 4069: 4066: 4065: 4063: 4059: 4056: 4054: 4051: 4050: 4049: 4046: 4044: 4041: 4039: 4036: 4034: 4031: 4029: 4025: 4021: 4019: 4016: 4012: 4009: 4008: 4007: 4004: 4003: 4000: 3997: 3995: 3991: 3981: 3978: 3976: 3973: 3971: 3968: 3966: 3963: 3961: 3958: 3956: 3953: 3949: 3946: 3945: 3944: 3941: 3937: 3932: 3931: 3930: 3927: 3926: 3924: 3922: 3918: 3910: 3907: 3905: 3902: 3900: 3897: 3896: 3895: 3892: 3890: 3887: 3885: 3882: 3880: 3877: 3875: 3872: 3870: 3867: 3865: 3862: 3861: 3859: 3857: 3856:Propositional 3853: 3847: 3844: 3842: 3839: 3837: 3834: 3832: 3829: 3827: 3824: 3822: 3819: 3815: 3812: 3811: 3810: 3807: 3805: 3802: 3800: 3797: 3795: 3792: 3790: 3787: 3785: 3784:Logical truth 3782: 3780: 3777: 3776: 3774: 3772: 3768: 3765: 3763: 3759: 3753: 3750: 3748: 3745: 3743: 3740: 3738: 3735: 3733: 3730: 3728: 3724: 3720: 3716: 3714: 3711: 3709: 3706: 3704: 3700: 3697: 3696: 3694: 3692: 3686: 3681: 3675: 3672: 3670: 3667: 3665: 3662: 3660: 3657: 3655: 3652: 3650: 3647: 3645: 3642: 3640: 3637: 3635: 3632: 3630: 3627: 3625: 3622: 3620: 3617: 3613: 3610: 3609: 3608: 3605: 3604: 3602: 3598: 3594: 3587: 3582: 3580: 3575: 3573: 3568: 3567: 3564: 3552: 3549: 3547: 3544: 3542: 3539: 3537: 3534: 3533: 3531: 3527: 3519: 3516: 3515: 3514: 3511: 3507: 3504: 3503: 3502: 3499: 3495: 3492: 3491: 3490: 3487: 3486: 3484: 3482: 3481:Digital logic 3478: 3472: 3469: 3467: 3464: 3462: 3459: 3458: 3456: 3454: 3450: 3444: 3441: 3439: 3436: 3435: 3433: 3431: 3427: 3421: 3418: 3417: 3415: 3413: 3409: 3403: 3400: 3398: 3395: 3393: 3390: 3389: 3387: 3385: 3384:Substructural 3381: 3375: 3372: 3370: 3367: 3365: 3362: 3360: 3357: 3355: 3352: 3351: 3349: 3347: 3343: 3337: 3334: 3332: 3329: 3327: 3324: 3322: 3319: 3317: 3314: 3313: 3311: 3309: 3305: 3301: 3294: 3289: 3287: 3282: 3280: 3275: 3274: 3271: 3265: 3264:0-486-40459-5 3261: 3257: 3253: 3251: 3247: 3243: 3231: 3225: 3221: 3220: 3214: 3213: 3202: 3198: 3192: 3184: 3178: 3174: 3167: 3159: 3152: 3145: 3141: 3135: 3129: 3124: 3117: 3111: 3103: 3101:9780141920870 3097: 3093: 3092: 3084: 3066: 3062: 3058: 3054: 3050: 3046: 3045: 3037: 3033: 3027: 3019: 3015: 3009: 3002: 2997: 2990: 2983: 2978: 2974: 2970: 2966: 2959: 2952: 2947: 2943: 2939: 2935: 2928: 2920: 2916: 2912: 2908: 2901: 2893: 2889: 2885: 2881: 2877: 2873: 2869: 2862: 2854: 2850: 2846: 2842: 2838: 2834: 2830: 2823: 2815: 2811: 2808:(1–2): 1–11. 2807: 2803: 2796: 2794: 2792: 2777: 2773: 2766: 2750: 2746: 2739: 2732: 2720: 2716: 2709: 2701: 2697: 2693: 2686: 2672: 2668: 2662: 2653: 2648: 2644: 2640: 2635: 2630: 2625: 2620: 2616: 2612: 2608: 2601: 2593: 2589: 2585: 2579: 2575: 2566: 2563: 2560: 2556: 2553: 2550: 2546: 2543: 2541: 2538: 2535: 2532: 2530: 2527: 2525: 2522: 2520: 2517: 2515: 2512: 2510: 2507: 2505: 2502: 2500: 2497: 2496: 2492: 2481: 2474: 2472: 2468: 2462: 2444: 2441: 2438: 2437: 2436: 2434: 2421: 2418: 2417: 2405: 2396: 2392: 2388: 2385: 2381: 2380: 2377: 2373: 2366:Bochvar logic 2363: 2361: 2356: 2354: 2348: 2344: 2340: 2336: 2329: 2325: 2321: 2317: 2313: 2309: 2293: 2290: 2287: 2283: 2279: 2276: 2273: 2269: 2265: 2262: 2259: 2252: 2241: 2233: 2223: 2210: 2206: 2202: 2198: 2194: 2190: 2182: 2172: 2166: 2163: 2161: 2157: 2153: 2149: 2145: 2141: 2135: 2129: 2119: 2117: 2112: 2103: 2099: 2095: 2090: 2089: 2088: 2081: 2077: 2073: 2068: 2067: 2066: 2054: 2051: 2048: 2044: 2040: 2037: 2034: 2030: 2026: 2023: 2020: 2013: 2002: 1994: 1984: 1980: 1969: 1963: 1959: 1956: 1952: 1947: 1944: 1939: 1935: 1932: 1928: 1924: 1923: 1922: 1919: 1912: 1908: 1902: 1897: 1893: 1888: 1883: 1879: 1873: 1869: 1864: 1860: 1855: 1853: 1839: 1835: 1831: 1827: 1823: 1819: 1815: 1804: 1801: 1794: 1790: 1786: 1782: 1778: 1774: 1770: 1759: 1756: 1749: 1745: 1741: 1737: 1733: 1729: 1725: 1714: 1711: 1707: 1701: 1698: 1694: 1691: 1687: 1684: 1680: 1677: 1673: 1669: 1666: 1662: 1659: 1655: 1651: 1648: 1644: 1643: 1642: 1635: 1631: 1627: 1623: 1619: 1615: 1611: 1607: 1603: 1599: 1595: 1591: 1588: 1584: 1580: 1576: 1572: 1568: 1567: 1566: 1554: 1551: 1548: 1544: 1540: 1537: 1534: 1530: 1526: 1523: 1520: 1513: 1502: 1494: 1484: 1477: 1474: 1471: 1467: 1463: 1460: 1457: 1453: 1449: 1446: 1443: 1436: 1425: 1417: 1407: 1403: 1400: 1398: 1394: 1388: 1378: 1376: 1372: 1367: 1361: 1349: 1346: 1343: 1339: 1335: 1332: 1329: 1325: 1321: 1318: 1315: 1308: 1297: 1289: 1279: 1272: 1269: 1266: 1262: 1258: 1255: 1252: 1248: 1244: 1241: 1238: 1231: 1220: 1212: 1202: 1198: 1181: 1175: 1169: 1124: 1116: 1110: 1102: 1099: 1097: 1094:is less than 1093: 1089: 1086:is less than 1085: 1081: 1077: 1073: 1069: 1064: 1062: 1058: 1054: 1050: 1046: 1042: 1038: 1034: 1030: 1026: 1022: 1018: 1014: 1010: 1006: 1001: 987: 984: 981: 977: 973: 970: 967: 963: 959: 956: 953: 946: 935: 927: 921: 914: 911: 908: 904: 900: 897: 894: 890: 886: 883: 880: 873: 862: 854: 848: 841: 838: 835: 831: 827: 824: 821: 817: 813: 810: 807: 800: 789: 781: 775: 768: 764: 760: 756: 752: 748: 740: 734: 728: 716: 713: 710: 706: 702: 699: 696: 692: 688: 685: 682: 675: 664: 656: 650: 643: 640: 637: 633: 629: 626: 623: 619: 615: 612: 609: 602: 591: 583: 577: 570: 567: 564: 560: 556: 553: 550: 546: 542: 539: 536: 529: 518: 510: 504: 497: 493: 489: 485: 481: 477: 469: 463: 457: 454: 452: 451:Graham Priest 448: 444: 438: 428: 426: 421: 417: 413: 409: 405: 401: 397: 393: 389: 386:allows 2 = 4 385: 384:Boolean logic 376: 374: 370: 365: 363: 359: 351: 347: 343: 340: 336: 332: 331: 326: 322: 318: 314: 310: 307: 303: 300: 299: 294: 290: 286: 283: 279: 276: 272: 271: 270: 268: 258: 256: 252: 246: 241: 239: 238:Hilary Putnam 235: 231: 220: 218: 214: 211:Around 1910, 207:Pre-discovery 204: 202: 198: 194: 190: 186: 182: 180: 176: 172: 171:Boolean logic 168: 164: 160: 156: 152: 148: 144: 140: 136: 132: 131:trinary logic 128: 124: 113: 110: 102: 91: 88: 84: 81: 77: 74: 70: 67: 63: 60: –  59: 55: 54:Find sources: 48: 44: 38: 37: 32:This article 30: 26: 21: 20: 5301: 5099:Ultraproduct 4946:Model theory 4911:Independence 4847:Formal proof 4839:Proof theory 4822: 4795: 4752:real numbers 4724:second-order 4635:Substitution 4512:Metalanguage 4453:conservative 4426:Axiom schema 4370:Constructive 4340:Morse–Kelley 4306:Set theories 4285:Aleph number 4278:inaccessible 4184:Grothendieck 4068:intersection 3955:Higher-order 3943:Second-order 3898: 3889:Truth tables 3846:Venn diagram 3629:Formal proof 3461:Three-valued 3460: 3402:Linear logic 3255: 3233:. Retrieved 3218: 3200: 3191: 3172: 3166: 3158:Sitz. Berlin 3157: 3151: 3143: 3134: 3123: 3110: 3090: 3083: 3072:. Retrieved 3048: 3042: 3036:"Third base" 3032:Hayes, Brian 3026: 3017: 3008: 2999: 2995: 2989: 2980: 2971:(5): 73–80. 2968: 2964: 2958: 2949: 2937: 2933: 2927: 2910: 2906: 2900: 2875: 2871: 2861: 2836: 2832: 2822: 2805: 2801: 2779:. Retrieved 2775: 2765: 2753:. Retrieved 2748: 2738: 2730: 2723:. Retrieved 2718: 2708: 2695: 2685: 2674:. Retrieved 2670: 2661: 2614: 2610: 2600: 2587: 2578: 2464: 2450:Applications 2439:Cohn algebra 2430: 2399: 2395:adding to it 2390: 2375: 2357: 2346: 2342: 2338: 2334: 2327: 2323: 2319: 2315: 2311: 2307: 2303: 2143: 2139: 2137: 2110: 2107: 2101: 2097: 2093: 2086: 2079: 2075: 2071: 2064: 1978: 1961: 1957: 1954: 1950: 1937: 1933: 1930: 1926: 1917: 1910: 1906: 1895: 1891: 1881: 1877: 1871: 1867: 1856: 1849: 1813: 1768: 1723: 1705: 1699: 1696: 1692: 1689: 1685: 1682: 1675: 1671: 1667: 1664: 1657: 1653: 1649: 1646: 1640: 1633: 1629: 1625: 1621: 1617: 1613: 1605: 1601: 1597: 1593: 1586: 1582: 1578: 1574: 1570: 1564: 1401: 1396: 1392: 1390: 1374: 1365: 1362: 1359: 1103: 1100: 1095: 1091: 1087: 1083: 1079: 1075: 1071: 1065: 1060: 1056: 1052: 1048: 1044: 1040: 1039:also equals 1036: 1032: 1028: 1024: 1020: 1016: 1012: 1008: 1004: 999: 997: 443:truth tables 440: 382: 366: 355: 349: 345: 338: 334: 328: 324: 320: 319:, and 0 for 316: 312: 296: 264: 248: 243: 226: 210: 200: 183: 178: 174: 162: 158: 155:truth values 146: 142: 138: 134: 130: 126: 120: 105: 99:January 2011 96: 86: 79: 72: 65: 53: 41:Please help 36:verification 33: 5209:Type theory 5157:undecidable 5089:Truth value 4976:equivalence 4655:non-logical 4268:Enumeration 4258:Isomorphism 4205:cardinality 4189:Von Neumann 4154:Ultrafilter 4119:Uncountable 4053:equivalence 3970:Quantifiers 3960:Fixed-point 3929:First-order 3809:Consistency 3794:Proposition 3771:Traditional 3742:Lindström's 3732:Compactness 3674:Type theory 3619:Cardinality 3501:Four-valued 3471:Łukasiewicz 3466:Four-valued 3453:Many-valued 3430:Description 3420:Dialetheism 2878:(1): 1–28. 2402:August 2014 1852:modal logic 420:implication 416:equivalence 373:connectives 330:undecidable 249:Similarly, 157:indicating 5324:Categories 5020:elementary 4713:arithmetic 4581:Quantifier 4559:functional 4431:Expression 4149:Transitive 4093:identities 4078:complement 4011:hereditary 3994:Set theory 3359:Fuzzy rule 3074:2020-04-12 2781:2020-07-30 2676:2024-05-15 2571:References 2461:Null (SQL) 1899:, and the 1375:designated 1366:designated 1082:such that 851:MAX(A, B) 778:MIN(A, B) 653:XOR(A, B) 507:AND(A, B) 435:See also: 335:irrelevant 325:unknowable 255:predicates 223:Motivation 215:defined a 69:newspapers 5291:Supertask 5194:Recursion 5152:decidable 4986:saturated 4964:of models 4887:deductive 4882:axiomatic 4802:Hilbert's 4789:Euclidean 4770:canonical 4693:axiomatic 4625:Signature 4554:Predicate 4443:Extension 4365:Ackermann 4290:Operation 4169:Universal 4159:Recursive 4134:Singleton 4129:Inhabited 4114:Countable 4104:Types of 4088:power set 4058:partition 3975:Predicate 3921:Predicate 3836:Syllogism 3826:Soundness 3799:Inference 3789:Tautology 3691:paradoxes 3513:IEEE 1164 3364:Fuzzy set 3235:24 August 2907:Semiotica 2892:0031-8108 2853:0031-8094 2643:0002-9327 2431:Some 3VL 1975:RM3 logic 1863:tautology 1399:, vol 8. 1114:→ 580:OR(A, B) 356:Inside a 135:trivalent 5276:Logicism 5269:timeline 5245:Concrete 5104:Validity 5074:T-schema 5067:Kripke's 5062:Tarski's 5057:semantic 5047:Strength 4996:submodel 4991:spectrum 4959:function 4807:Tarski's 4796:Elements 4783:geometry 4739:Robinson 4660:variable 4645:function 4618:spectrum 4608:Sentence 4564:variable 4507:Language 4460:Relation 4421:Automata 4411:Alphabet 4395:language 4249:-jection 4227:codomain 4213:Function 4174:Universe 4144:Infinite 4048:Relation 3831:Validity 3821:Argument 3719:theorem, 3160:. 42–56. 3065:Archived 3053:Sigma Xi 3016:(1981). 2700:Archived 2592:Archived 2477:See also 2122:HT logic 348:, 1 for 315:, 2 for 167:bivalent 5218:Related 5015:Diagram 4913: ( 4892:Hilbert 4877:Systems 4872:Theorem 4750:of the 4695:systems 4475:Formula 4470:Grammar 4386: ( 4330:General 4043:Forcing 4028:Element 3948:Monadic 3723:paradox 3664:Theorem 3600:General 3506:Verilog 2755:May 15, 2725:May 15, 2696:Commens 2652:2370324 2314:) → ((( 2230:(A, B) 2152:Heyting 1991:(A, B) 1414:(A, B) 1092:unknown 1088:unknown 1076:unknown 1057:unknown 1051:equals 1049:unknown 1043:, then 1027:equals 1017:unknown 1005:unknown 1000:unknown 737:NEG(A) 466:NOT(A) 321:unknown 304:in the 291:, each 287:in the 280:in the 143:trilean 139:ternary 83:scholar 4981:finite 4744:Skolem 4697:  4672:Theory 4640:Symbol 4630:String 4613:atomic 4490:ground 4485:closed 4480:atomic 4436:ground 4399:syntax 4295:binary 4222:domain 4139:Finite 3904:finite 3762:Logics 3721:  3669:Theory 3529:Others 3262:  3226:  3179:  3098:  2890:  2851:  2649:  2641:  2360:coatom 2235:A → B 2146:or as 1996:A → B 1496:A → B 1419:A → B 1291:A → B 1214:A → B 1179:  1157:  1144:  1120:  1031:, and 929:A ⊕ B 856:A ∨ B 783:A ∧ B 658:A ⊕ B 585:A ∨ B 512:A ∧ B 379:Logics 344:0 for 311:1 for 129:(also 85:  78:  71:  64:  56:  4971:Model 4719:Peano 4576:Proof 4416:Arity 4345:Naive 4232:image 4164:Fuzzy 4124:Empty 4073:union 4018:Class 3659:Model 3649:Lemma 3607:Axiom 3346:Fuzzy 3068:(PDF) 3051:(6). 3039:(PDF) 2647:JSTOR 2547:(and 2534:Setun 2148:Gödel 1628:) ∧ ( 1600:= ¬(¬ 1369:(The 1084:false 1072:false 1037:false 1013:false 346:false 337:, or 317:false 295:is a 293:digit 179:false 163:false 141:, or 123:logic 90:JSTOR 76:books 5094:Type 4897:list 4701:list 4678:list 4667:Term 4601:rank 4495:open 4389:list 4201:Maps 4106:sets 3965:Free 3935:list 3685:list 3612:list 3518:VHDL 3260:ISBN 3237:2013 3224:ISBN 3177:ISBN 3096:ISBN 2911:2021 2888:ISSN 2849:ISSN 2757:2023 2727:2023 2639:ISSN 2471:NULL 2326:) → 2322:) → 2179:(A) 2100:) → 1875:and 1604:∨ ¬ 1585:) → 1393:true 1096:true 1090:and 1080:true 1078:and 1061:true 1053:true 1045:true 1041:true 1033:true 1029:true 1025:true 1021:true 1009:true 412:XNOR 396:NAND 350:true 339:both 313:true 298:trit 191:and 177:and 175:true 159:true 125:, a 62:news 4781:of 4763:of 4711:of 4243:Sur 4217:Map 4024:Ur- 4006:Set 3246:doi 3057:doi 2973:doi 2942:doi 2915:doi 2880:doi 2841:doi 2810:doi 2629:hdl 2619:doi 2467:SQL 2455:SQL 2397:. 2341:)∨( 2337:∨(¬ 2291:NF 2271:NF 2246:NF 2226:IMP 2200:NF 2187:¬A 2175:NOT 2144:SmT 2074:→ ( 1989:RM3 1987:IMP 1960:∧ ¬ 1953:∧ ¬ 1936:∨ ¬ 1909:∧ ¬ 1894:∨ ¬ 1695:∧ ¬ 1670:= ¬ 1652:= ¬ 1620:= ( 1577:= ( 1555:+1 1549:−1 1546:+1 1541:+1 1538:+1 1527:+1 1524:+1 1521:+1 1518:−1 1510:+1 1504:−1 1487:IMP 1410:IMP 1350:+1 1344:−1 1341:+1 1336:+1 1322:+1 1319:+1 1316:+1 1313:−1 1305:+1 1299:−1 1282:IMP 1205:IMP 1162:NOT 1047:OR 1035:OR 1023:OR 1011:or 988:−1 982:+1 979:+1 960:+1 954:−1 951:−1 943:+1 937:−1 915:+1 912:+1 909:+1 906:+1 901:+1 887:+1 881:−1 878:−1 870:+1 864:−1 842:+1 836:−1 833:+1 822:−1 814:−1 811:−1 808:−1 805:−1 797:+1 791:−1 769:−1 766:+1 753:+1 750:−1 745:¬A 474:¬A 408:XOR 404:NOR 394:, 392:AND 273:in 147:3VL 121:In 45:by 5326:: 5167:NP 4791:: 4785:: 4715:: 4392:), 4247:Bi 4239:In 3063:. 3049:89 3047:. 3041:. 2979:. 2967:. 2948:. 2938:77 2936:. 2909:. 2886:. 2876:66 2874:. 2870:. 2847:. 2835:. 2831:. 2806:24 2804:. 2790:^ 2774:. 2747:. 2729:. 2717:. 2698:. 2694:. 2669:. 2645:. 2637:. 2627:. 2615:43 2613:. 2609:. 2586:. 2345:→ 2318:→ 2310:→ 2306:(¬ 2294:T 2288:F 2285:T 2280:T 2277:T 2274:F 2266:T 2263:T 2260:T 2257:F 2254:A 2249:T 2243:F 2238:B 2228:HT 2211:F 2208:T 2203:F 2195:T 2192:F 2184:A 2177:HT 2140:HT 2096:⊗ 2082:)) 2078:→ 2055:T 2052:F 2049:F 2046:T 2041:T 2038:U 2035:F 2032:U 2027:T 2024:T 2021:T 2018:F 2015:A 2010:T 2007:U 2004:F 1999:B 1970:). 1949:¬( 1929:∨ 1905:¬( 1903:, 1889:, 1880:↔ 1870:→ 1840:F 1837:T 1832:T 1829:U 1824:F 1821:F 1795:T 1792:T 1787:F 1784:U 1779:F 1776:F 1750:T 1747:T 1742:T 1739:U 1734:F 1731:F 1688:= 1656:→ 1632:→ 1624:→ 1616:⇔ 1596:∧ 1581:→ 1573:∨ 1552:0 1535:0 1532:0 1515:A 1507:0 1499:B 1478:T 1475:U 1472:F 1469:T 1464:T 1461:T 1458:U 1455:U 1450:T 1447:T 1444:T 1441:F 1438:A 1433:T 1430:U 1427:F 1422:B 1347:0 1333:0 1330:0 1327:0 1310:A 1302:0 1294:B 1273:T 1270:U 1267:F 1264:T 1259:T 1256:U 1253:U 1250:U 1245:T 1242:T 1239:T 1236:F 1233:A 1228:T 1225:U 1222:F 1217:B 1149:OR 1074:, 985:0 974:0 971:0 968:0 965:0 957:0 948:A 940:0 932:B 898:0 895:0 892:0 884:0 875:A 867:0 859:B 839:0 828:0 825:0 819:0 802:A 794:0 786:B 761:0 758:0 742:A 717:F 714:U 711:T 708:T 703:U 700:U 697:U 694:U 689:T 686:U 683:F 680:F 677:A 672:T 669:U 666:F 661:B 644:T 641:T 638:T 635:T 630:T 627:U 624:U 621:U 616:T 613:U 610:F 607:F 604:A 599:T 596:U 593:F 588:B 571:T 568:U 565:F 562:T 557:U 554:U 551:F 548:U 543:F 540:F 537:F 534:F 531:A 526:T 523:U 520:F 515:B 498:F 495:T 490:U 487:U 482:T 479:F 471:A 410:, 406:, 402:, 400:OR 398:, 364:. 333:, 323:, 181:. 161:, 137:, 133:, 5247:/ 5162:P 4917:) 4703:) 4699:( 4596:∀ 4591:! 4586:∃ 4547:= 4542:↔ 4537:→ 4532:∧ 4527:∨ 4522:¬ 4245:/ 4241:/ 4215:/ 4026:) 4022:( 3909:∞ 3899:3 3687:) 3585:e 3578:t 3571:v 3292:e 3285:t 3278:v 3248:: 3239:. 3185:. 3104:. 3077:. 3059:: 2975:: 2969:8 2944:: 2921:. 2917:: 2894:. 2882:: 2855:. 2843:: 2837:3 2816:. 2812:: 2784:. 2759:. 2679:. 2655:. 2631:: 2621:: 2561:) 2557:( 2551:) 2404:) 2400:( 2349:) 2347:q 2343:p 2339:q 2335:p 2330:) 2328:p 2324:p 2320:q 2316:p 2312:p 2308:q 2111:U 2102:A 2098:B 2094:A 2092:( 2080:A 2076:B 2072:A 2070:( 1966:( 1964:) 1962:A 1958:A 1955:I 1951:A 1945:) 1941:( 1938:A 1934:A 1931:I 1927:A 1918:I 1913:) 1911:A 1907:A 1896:A 1892:A 1882:A 1878:A 1872:A 1868:A 1814:A 1812:I 1807:A 1769:A 1767:L 1762:A 1724:A 1722:M 1717:A 1700:A 1697:L 1693:A 1690:M 1686:A 1683:I 1676:A 1674:¬ 1672:M 1668:A 1665:L 1658:A 1654:A 1650:A 1647:M 1636:) 1634:A 1630:B 1626:B 1622:A 1618:B 1614:A 1608:) 1606:B 1602:A 1598:B 1594:A 1587:B 1583:B 1579:A 1575:B 1571:A 1489:Ł 1412:Ł 1284:K 1207:K 1185:) 1182:B 1176:, 1173:) 1170:A 1167:( 1154:( 1137:f 1134:e 1131:d 1125:= 1117:B 1111:A 414:( 341:; 327:/ 201:n 112:) 106:( 101:) 97:( 87:· 80:· 73:· 66:· 39:.

Index


verification
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"Three-valued logic"
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logic
many-valued logic
truth values
bivalent
Boolean logic
Emil Leon Post
Jan Łukasiewicz
Clarence Irving Lewis
Grigore Constantin Moisil
Charles Sanders Peirce
many-valued logic system
problem of future contingents
Bruno de Finetti
Hilary Putnam
Stephen Cole Kleene
predicates
ternary numeral system
balanced ternary
redundant binary representation

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