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Existential quantification

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2151:, when conducted in a Fitch style deduction, proceeds by entering a new sub-derivation while substituting an existentially quantified variable for a subject—which does not appear within any active sub-derivation. If a conclusion can be reached within this sub-derivation in which the substituted subject does not appear, then one can exit that sub-derivation with that conclusion. The reasoning behind existential elimination (∃E) is as follows: If it is given that there exists an element for which the proposition function is true, and if a conclusion can be reached by giving that element an arbitrary name, that conclusion is 4784: 3027: 3016: 1563: 1802: 1391: 1372: 1657: 2076:(∃I) concludes that, if the propositional function is known to be true for a particular element of the domain of discourse, then it must be true that there exists an element for which the proposition function is true. Symbolically, 2264: 1558:{\displaystyle \lnot \ \exists {x}{\in }\mathbf {X} \,P(x)\equiv \ \forall {x}{\in }\mathbf {X} \,\lnot P(x)\not \equiv \ \lnot \ \forall {x}{\in }\mathbf {X} \,P(x)\equiv \ \exists {x}{\in }\mathbf {X} \,\lnot P(x)} 1667: 2143: 1384:
A common error is stating "all persons are not married" (i.e., "there exists no person who is married"), when "not all persons are married" (i.e., "there exists a person who is not married") is intended:
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If there is no element of the domain of discourse for which the statement is true, then it must be false for all of those elements. That is, the negation of
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is a rule justifying a logical step from hypothesis to conclusion. There are several rules of inference which utilize the existential quantifier.
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popularised its use as the existential quantifier. Through his research in set theory, Peano also introduced the symbols
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This can be demonstrated to be false. Truthfully, it must be said, "It is not the case that there is a natural number
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This is a single statement using existential quantification. It is roughly analogous to the informal sentence "Either
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A quantified propositional function is a statement; thus, like statements, quantified functions can be negated. The
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are used to restrict the domain of discourse to fulfill a given predicate. For example, the sentence
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Unlike the universal quantifier, the existential quantifier distributes over logical disjunctions:
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font, Unicode U+2203) is used to indicate existential quantification. For example, the notation
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is not arbitrary, and is instead a specific element of the domain of discourse, then stating
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This particular example is true, because 5 is a natural number, and when we substitute 5 for
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Negation is also expressible through a statement of "for no", as opposed to "for some":
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as "there exists", "there is at least one", or "for some". It is usually denoted by the
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of all natural numbers, the existential quantification "There exists a natural number
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is allowed to take, is therefore critical to a statement's trueness or falseness.
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of an existential statement about "some" object may be achieved either by a
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which is greater than 0 and less than 1" can be symbolically stated as:
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is greater than 0 and less than 1", then, for a domain of discourse
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is enough to prove this existential quantification to be true.
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that is greater than 0 and less than 1", or, symbolically:
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to respectively denote the intersection and union of sets.
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of that propositional function's negation; symbolically,
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Quantification in general is covered in the article on
2454:, the existential quantifier can be understood as the 2394: 2340: 2274: 2176: 2085: 1670: 1577: 1394: 1286: 1221: 1159: 1098: 1040: 991: 958: 938: 888: 864: 807: 794: 739: 719: 699: 656: 636: 614:" is false, because there are no even solutions. The 588: 568: 526: 494: 447: 415: 383: 347: 327: 173: 146: 117: 82: 2373:{\displaystyle \exists {x}{\in }\varnothing \,P(x)} 1204:is logically equivalent to "For any natural number 1194:{\displaystyle \exists {x}{\in }\mathbf {X} \,P(x)} 1075:{\displaystyle \exists {x}{\in }\mathbf {X} \,P(x)} 2470:functor of a function between sets; likewise, the 2400: 2372: 2298: 2258: 2137: 1796: 1651: 1557: 1366: 1258: 1193: 1138: 1074: 1000: 964: 944: 906: 870: 846: 757: 725: 705: 674: 642: 606: 574: 544: 512: 465: 433: 401: 365: 333: 194: 152: 132: 103: 1920: 477:to be the natural numbers, not, for example, the 269:members of the domain. Some sources use the term 30:"∃" redirects here. For the letter turned E, see 4800: 2000: 1969: 1861: 261:). Existential quantification is distinct from 3056: 2739: 2014: 1983: 1881: 1874: 918:The symbol's first usage is thought to be by 2636: 1212:is not greater than 0 and less than 1", or: 280:. The existential quantifier is encoded as 3248: 3063: 3049: 2753: 2746: 2732: 2703: 2442:Universal quantification § As adjoint 618:, which specifies the values the variable 2609: 2357: 2195: 2122: 1778: 1744: 1689: 1636: 1596: 1539: 1502: 1456: 1419: 1348: 1311: 1240: 1178: 1123: 1059: 822: 2536: 273:to refer to existential quantification. 2630: 14: 4801: 3070: 2314:; else, the logic does not follow: If 3044: 2727: 2428:) – exist in the empty set. See also 1806: 2610:Allen, Colin; Hand, Michael (2001). 2643:. Springer Cham. pp. 210–211. 1273:'s existential quantification is a 1269:Generally, then, the negation of a 1008:symbol is used to denote negation. 24: 2706:Fundamentals of Mathematical Logic 2416:of any description – let alone an 2341: 2177: 2104: 1760: 1726: 1671: 1618: 1612: 1540: 1521: 1484: 1478: 1457: 1438: 1401: 1395: 1349: 1330: 1293: 1287: 1241: 1222: 1160: 1105: 1099: 1041: 992: 808: 174: 140:is true for at least one value of 83: 27:Mathematical use of "there exists" 25: 4825: 2354: 4782: 3025: 3014: 2329: 2191: 2118: 1774: 1740: 1685: 1632: 1592: 1535: 1498: 1452: 1415: 1344: 1307: 1236: 1174: 1119: 1055: 854:represents the (true) statement 488:, we produce the true statement 2380:is always false, regardless of 2306:must be true for all values of 34:. For the Japanese kana ヨ, see 2665: 2603: 2579: 2555: 2530: 2367: 2361: 2287: 2284: 2278: 2253: 2244: 2241: 2232: 2229: 2223: 2217: 2214: 2208: 2205: 2199: 2132: 2126: 2098: 2095: 2089: 1791: 1788: 1782: 1754: 1748: 1723: 1717: 1714: 1708: 1699: 1693: 1646: 1640: 1606: 1600: 1552: 1546: 1512: 1506: 1469: 1463: 1429: 1423: 1361: 1355: 1321: 1315: 1253: 1247: 1188: 1182: 1133: 1127: 1069: 1063: 189: 183: 127: 121: 98: 92: 13: 1: 4743:History of mathematical logic 2696: 2676:Sheaves in Geometry and Logic 2435: 2420:fulfilling a given predicate 1377:(This is a generalization of 975: 630:For some positive odd number 305:and related formula editors. 195:{\displaystyle \exists xP(x)} 104:{\displaystyle \exists xP(x)} 4668:Primitive recursive function 2563:"Predicates and Quantifiers" 2401:{\displaystyle \varnothing } 907:{\displaystyle n\times n=25} 758:{\displaystyle n\times n=25} 675:{\displaystyle n\times n=25} 607:{\displaystyle n\times n=25} 545:{\displaystyle n\times n=25} 513:{\displaystyle 5\times 5=25} 466:{\displaystyle 2\times 2=25} 434:{\displaystyle 1\times 1=25} 402:{\displaystyle 0\times 0=25} 366:{\displaystyle n\times n=25} 7: 2481: 2299:{\displaystyle P(c)\to \ Q} 980: 784: 520:. It does not matter that " 10: 4830: 3732:Schröder–Bernstein theorem 3459:Monadic predicate calculus 3118:Foundations of mathematics 2510:– for the unicode symbol ∃ 2439: 2051:Existential generalization 1856:Biconditional introduction 213:existential quantification 49:Existential quantification 40: 29: 4778: 4765:Philosophy of mathematics 4714:Automated theorem proving 4696: 4591: 4423: 4316: 4168: 3885: 3861: 3839:Von Neumann–Bernays–Gödel 3784: 3678: 3582: 3480: 3471: 3398: 3333: 3239: 3161: 3078: 3011: 2762: 2674:, Ieke Moerdijk, (1992): 2649:10.1007/978-3-319-71350-2 2537:Bergmann, Merrie (2014). 2519:Uniqueness quantification 2149:Existential instantiation 308: 164: 73: 63: 53: 2524: 2073:Existential introduction 2042:Universal generalization 1882:Disjunction introduction 1869:Conjunction introduction 1839:Implication introduction 1275:universal quantification 1001:{\displaystyle \lnot \ } 793:, "∃" (a turned letter " 693:For some natural number 321:For some natural number 263:universal quantification 4415:Self-verifying theories 4236:Tarski's axiomatization 3187:Tarski's undefinability 3182:incompleteness theorems 559:In contrast, "For some 4789:Mathematics portal 4400:Proof of impossibility 4048:propositional variable 3358:Propositional calculus 3032:Mathematics portal 2432:for more information. 2402: 2374: 2300: 2260: 2159:and for a proposition 2139: 1901:hypothetical syllogism 1822:Propositional calculus 1798: 1653: 1559: 1368: 1271:propositional function 1260: 1195: 1140: 1076: 1002: 966: 946: 925:Formulario mathematico 908: 872: 848: 759: 727: 707: 676: 644: 608: 576: 546: 514: 467: 435: 403: 367: 335: 278:quantification (logic) 236:existential quantifier 196: 154: 134: 105: 4658:Kolmogorov complexity 4611:Computably enumerable 4511:Model complete theory 4303:Principia Mathematica 3363:Propositional formula 3192:Banach–Tarski paradox 3021:Philosophy portal 2637:Stephen Webb (2018). 2508:List of logic symbols 2403: 2375: 2310:over the same domain 2301: 2261: 2140: 1943:Negation introduction 1936:modus ponendo tollens 1799: 1654: 1560: 1381:to predicate logic.) 1369: 1261: 1196: 1141: 1077: 1003: 967: 965:{\displaystyle \cup } 947: 945:{\displaystyle \cap } 909: 873: 849: 779:nonconstructive proof 760: 728: 708: 677: 645: 609: 577: 547: 515: 468: 436: 404: 368: 336: 197: 155: 135: 106: 4606:Church–Turing thesis 4593:Computability theory 3802:continuum hypothesis 3320:Square of opposition 3178:Gödel's completeness 2503:Lindström quantifier 2472:universal quantifier 2392: 2338: 2272: 2174: 2083: 2001:Material implication 1952:Rules of replacement 1815:Transformation rules 1668: 1575: 1392: 1284: 1219: 1157: 1096: 1038: 1019:) is the predicate " 989: 956: 936: 928:(1896). Afterwards, 886: 862: 805: 737: 717: 697: 687:logically equivalent 654: 634: 624:Logical conjunctions 586: 566: 524: 492: 445: 413: 381: 345: 325: 171: 144: 133:{\displaystyle P(x)} 115: 80: 4760:Mathematical object 4651:P versus NP problem 4616:Computable function 4410:Reverse mathematics 4336:Logical consequence 4213:primitive recursive 4208:elementary function 3981:Free/bound variable 3834:Tarski–Grothendieck 3353:Logical connectives 3283:Logical equivalence 3133:Logical consequence 2704:Hinman, P. (2005). 2514:Quantifier variance 2388:). This is because 1914:destructive dilemma 616:domain of discourse 475:domain of discourse 50: 4814:Quantifier (logic) 4558:Transfer principle 4521:Semantics of logic 4506:Categorical theory 4482:Non-standard model 3996:Logical connective 3123:Information theory 3072:Mathematical logic 2488:Existential clause 2450:and the theory of 2398: 2370: 2296: 2256: 2135: 2033:Rules of inference 1829:Rules of inference 1807:Rules of inference 1794: 1649: 1555: 1364: 1256: 1191: 1136: 1072: 998: 962: 942: 904: 868: 858:There exists some 844: 775:constructive proof 771:mathematical proof 755: 723: 703: 672: 640: 604: 572: 542: 510: 463: 431: 399: 363: 331: 271:existentialization 192: 165:Symbolic statement 150: 130: 101: 68:Mathematical logic 48: 4796: 4795: 4728:Abstract category 4531:Theories of truth 4341:Rule of inference 4331:Natural deduction 4312: 4311: 3857: 3856: 3562:Cartesian product 3467: 3466: 3373:Many-valued logic 3348:Boolean functions 3231:Russell's paradox 3206:diagonal argument 3103:First-order logic 3038: 3037: 3006: 3005: 2672:Saunders Mac Lane 2658:978-3-319-71349-6 2587:"1.2 Quantifiers" 2548:978-0-07-803841-9 2498:First-order logic 2493:Existence theorem 2292: 2249: 2237: 2213: 2167:does not appear: 2103: 2066:rule of inference 2062: 2061: 1722: 1617: 1520: 1483: 1477: 1437: 1400: 1329: 1292: 1104: 997: 871:{\displaystyle n} 726:{\displaystyle n} 706:{\displaystyle n} 643:{\displaystyle n} 575:{\displaystyle n} 334:{\displaystyle n} 205: 204: 153:{\displaystyle x} 16:(Redirected from 4821: 4787: 4786: 4738:History of logic 4733:Category of sets 4626:Decision problem 4405:Ordinal analysis 4346:Sequent calculus 4244:Boolean algebras 4184: 4183: 4158: 4129:logical/constant 3883: 3882: 3869: 3792:Zermelo–Fraenkel 3543:Set operations: 3478: 3477: 3415: 3246: 3245: 3226:Löwenheim–Skolem 3113:Formal semantics 3065: 3058: 3051: 3042: 3041: 3030: 3029: 3019: 3018: 3017: 2863: 2812: 2778: 2765: 2764: 2748: 2741: 2734: 2725: 2724: 2719: 2691: 2678:Springer-Verlag 2669: 2663: 2662: 2640:Clash of Symbols 2634: 2628: 2627: 2607: 2601: 2600: 2598: 2597: 2583: 2577: 2576: 2574: 2573: 2567:www.csm.ornl.gov 2559: 2553: 2552: 2534: 2452:elementary topoi 2407: 2405: 2404: 2399: 2379: 2377: 2376: 2371: 2353: 2348: 2305: 2303: 2302: 2297: 2290: 2265: 2263: 2262: 2257: 2247: 2235: 2211: 2194: 2189: 2184: 2153:necessarily true 2144: 2142: 2141: 2136: 2121: 2116: 2111: 2101: 2016: 2009: 2002: 1990:De Morgan's laws 1985: 1978: 1971: 1964: 1938: 1930: 1922: 1915: 1909: 1902: 1896: 1889: 1883: 1876: 1870: 1863: 1857: 1850: 1840: 1811: 1810: 1803: 1801: 1800: 1795: 1777: 1772: 1767: 1743: 1738: 1733: 1720: 1688: 1683: 1678: 1658: 1656: 1655: 1650: 1635: 1630: 1625: 1615: 1595: 1590: 1585: 1564: 1562: 1561: 1556: 1538: 1533: 1528: 1518: 1501: 1496: 1491: 1481: 1475: 1455: 1450: 1445: 1435: 1418: 1413: 1408: 1398: 1379:De Morgan's laws 1373: 1371: 1370: 1365: 1347: 1342: 1337: 1327: 1310: 1305: 1300: 1290: 1265: 1263: 1262: 1257: 1239: 1234: 1229: 1200: 1198: 1197: 1192: 1177: 1172: 1167: 1145: 1143: 1142: 1137: 1122: 1117: 1112: 1102: 1081: 1079: 1078: 1073: 1058: 1053: 1048: 1011:For example, if 1007: 1005: 1004: 999: 995: 971: 969: 968: 963: 951: 949: 948: 943: 930:Bertrand Russell 913: 911: 910: 905: 877: 875: 874: 869: 853: 851: 850: 845: 825: 820: 815: 764: 762: 761: 756: 732: 730: 729: 724: 712: 710: 709: 704: 689:to the sentence 681: 679: 678: 673: 649: 647: 646: 641: 613: 611: 610: 605: 581: 579: 578: 573: 551: 549: 548: 543: 519: 517: 516: 511: 472: 470: 469: 464: 440: 438: 437: 432: 408: 406: 405: 400: 372: 370: 369: 364: 340: 338: 337: 332: 300: 292: 289: 286: 284: 260: 252: 244: 229:logical operator 221:logical constant 201: 199: 198: 193: 159: 157: 156: 151: 139: 137: 136: 131: 110: 108: 107: 102: 51: 47: 21: 4829: 4828: 4824: 4823: 4822: 4820: 4819: 4818: 4799: 4798: 4797: 4792: 4781: 4774: 4719:Category theory 4709:Algebraic logic 4692: 4663:Lambda calculus 4601:Church encoding 4587: 4563:Truth predicate 4419: 4385:Complete theory 4308: 4177: 4173: 4169: 4164: 4156: 3876: and  3872: 3867: 3853: 3829:New Foundations 3797:axiom of choice 3780: 3742:Gödel numbering 3682: and  3674: 3578: 3463: 3413: 3394: 3343:Boolean algebra 3329: 3293:Equiconsistency 3258:Classical logic 3235: 3216:Halting problem 3204: and  3180: and  3168: and  3167: 3162:Theorems ( 3157: 3074: 3069: 3039: 3034: 3024: 3023: 3015: 3013: 3007: 3002: 2998: 2990: 2986: 2978: 2975: 2972: 2964: 2961: 2958: 2950: 2946: 2941: 2933: 2929: 2924: 2916: 2915: 2912: 2908: 2900: 2899: 2896: 2892: 2884: 2880: 2872: 2868: 2859: 2850: 2846: 2841: 2833: 2829: 2821: 2817: 2808: 2799: 2795: 2787: 2783: 2774: 2758: 2756:logical symbols 2752: 2722: 2716: 2699: 2694: 2670: 2666: 2659: 2635: 2631: 2624: 2608: 2604: 2595: 2593: 2591:www.whitman.edu 2585: 2584: 2580: 2571: 2569: 2561: 2560: 2556: 2549: 2541:. McGraw Hill. 2535: 2531: 2527: 2484: 2448:category theory 2444: 2438: 2393: 2390: 2389: 2349: 2344: 2339: 2336: 2335: 2332: 2273: 2270: 2269: 2190: 2185: 2180: 2175: 2172: 2171: 2117: 2112: 2107: 2084: 2081: 2080: 2026:Predicate logic 2020: 1984:Double negation 1838: 1809: 1773: 1768: 1763: 1739: 1734: 1729: 1684: 1679: 1674: 1669: 1666: 1665: 1631: 1626: 1621: 1591: 1586: 1581: 1576: 1573: 1572: 1534: 1529: 1524: 1497: 1492: 1487: 1451: 1446: 1441: 1414: 1409: 1404: 1393: 1390: 1389: 1343: 1338: 1333: 1306: 1301: 1296: 1285: 1282: 1281: 1235: 1230: 1225: 1220: 1217: 1216: 1173: 1168: 1163: 1158: 1155: 1154: 1118: 1113: 1108: 1097: 1094: 1093: 1054: 1049: 1044: 1039: 1036: 1035: 990: 987: 986: 983: 978: 957: 954: 953: 937: 934: 933: 887: 884: 883: 880:natural numbers 863: 860: 859: 821: 816: 811: 806: 803: 802: 787: 738: 735: 734: 718: 715: 714: 698: 695: 694: 655: 652: 651: 635: 632: 631: 587: 584: 583: 567: 564: 563: 525: 522: 521: 493: 490: 489: 446: 443: 442: 414: 411: 410: 382: 379: 378: 346: 343: 342: 326: 323: 322: 311: 298: 290: 287: 282: 281: 254: 246: 239: 209:predicate logic 172: 169: 168: 145: 142: 141: 116: 113: 112: 81: 78: 77: 46: 43:K41 (nightclub) 39: 28: 23: 22: 15: 12: 11: 5: 4827: 4817: 4816: 4811: 4794: 4793: 4779: 4776: 4775: 4773: 4772: 4767: 4762: 4757: 4752: 4751: 4750: 4740: 4735: 4730: 4721: 4716: 4711: 4706: 4704:Abstract logic 4700: 4698: 4694: 4693: 4691: 4690: 4685: 4683:Turing machine 4680: 4675: 4670: 4665: 4660: 4655: 4654: 4653: 4648: 4643: 4638: 4633: 4623: 4621:Computable set 4618: 4613: 4608: 4603: 4597: 4595: 4589: 4588: 4586: 4585: 4580: 4575: 4570: 4565: 4560: 4555: 4550: 4549: 4548: 4543: 4538: 4528: 4523: 4518: 4516:Satisfiability 4513: 4508: 4503: 4502: 4501: 4491: 4490: 4489: 4479: 4478: 4477: 4472: 4467: 4462: 4457: 4447: 4446: 4445: 4440: 4433:Interpretation 4429: 4427: 4421: 4420: 4418: 4417: 4412: 4407: 4402: 4397: 4387: 4382: 4381: 4380: 4379: 4378: 4368: 4363: 4353: 4348: 4343: 4338: 4333: 4328: 4322: 4320: 4314: 4313: 4310: 4309: 4307: 4306: 4298: 4297: 4296: 4295: 4290: 4289: 4288: 4283: 4278: 4258: 4257: 4256: 4254:minimal axioms 4251: 4240: 4239: 4238: 4227: 4226: 4225: 4220: 4215: 4210: 4205: 4200: 4187: 4185: 4166: 4165: 4163: 4162: 4161: 4160: 4148: 4143: 4142: 4141: 4136: 4131: 4126: 4116: 4111: 4106: 4101: 4100: 4099: 4094: 4084: 4083: 4082: 4077: 4072: 4067: 4057: 4052: 4051: 4050: 4045: 4040: 4030: 4029: 4028: 4023: 4018: 4013: 4008: 4003: 3993: 3988: 3983: 3978: 3977: 3976: 3971: 3966: 3961: 3951: 3946: 3944:Formation rule 3941: 3936: 3935: 3934: 3929: 3919: 3918: 3917: 3907: 3902: 3897: 3892: 3886: 3880: 3863:Formal systems 3859: 3858: 3855: 3854: 3852: 3851: 3846: 3841: 3836: 3831: 3826: 3821: 3816: 3811: 3806: 3805: 3804: 3799: 3788: 3786: 3782: 3781: 3779: 3778: 3777: 3776: 3766: 3761: 3760: 3759: 3752:Large cardinal 3749: 3744: 3739: 3734: 3729: 3715: 3714: 3713: 3708: 3703: 3688: 3686: 3676: 3675: 3673: 3672: 3671: 3670: 3665: 3660: 3650: 3645: 3640: 3635: 3630: 3625: 3620: 3615: 3610: 3605: 3600: 3595: 3589: 3587: 3580: 3579: 3577: 3576: 3575: 3574: 3569: 3564: 3559: 3554: 3549: 3541: 3540: 3539: 3534: 3524: 3519: 3517:Extensionality 3514: 3512:Ordinal number 3509: 3499: 3494: 3493: 3492: 3481: 3475: 3469: 3468: 3465: 3464: 3462: 3461: 3456: 3451: 3446: 3441: 3436: 3431: 3430: 3429: 3419: 3418: 3417: 3404: 3402: 3396: 3395: 3393: 3392: 3391: 3390: 3385: 3380: 3370: 3365: 3360: 3355: 3350: 3345: 3339: 3337: 3331: 3330: 3328: 3327: 3322: 3317: 3312: 3307: 3302: 3297: 3296: 3295: 3285: 3280: 3275: 3270: 3265: 3260: 3254: 3252: 3243: 3237: 3236: 3234: 3233: 3228: 3223: 3218: 3213: 3208: 3196:Cantor's  3194: 3189: 3184: 3174: 3172: 3159: 3158: 3156: 3155: 3150: 3145: 3140: 3135: 3130: 3125: 3120: 3115: 3110: 3105: 3100: 3095: 3094: 3093: 3082: 3080: 3076: 3075: 3068: 3067: 3060: 3053: 3045: 3036: 3035: 3012: 3009: 3008: 3004: 3003: 2994: 2993: 2991: 2982: 2981: 2979: 2968: 2967: 2965: 2954: 2953: 2951: 2937: 2936: 2934: 2920: 2919: 2917: 2913:quantification 2909: 2904: 2903: 2901: 2897:quantification 2893: 2888: 2887: 2885: 2876: 2875: 2873: 2854: 2853: 2851: 2837: 2836: 2834: 2825: 2824: 2822: 2803: 2802: 2800: 2791: 2790: 2788: 2769: 2768: 2763: 2760: 2759: 2751: 2750: 2743: 2736: 2728: 2721: 2720: 2714: 2708:. A K Peters. 2700: 2698: 2695: 2693: 2692: 2664: 2657: 2629: 2622: 2602: 2578: 2554: 2547: 2539:The Logic Book 2528: 2526: 2523: 2522: 2521: 2516: 2511: 2505: 2500: 2495: 2490: 2483: 2480: 2440:Main article: 2437: 2434: 2397: 2369: 2366: 2363: 2360: 2356: 2352: 2347: 2343: 2331: 2328: 2295: 2289: 2286: 2283: 2280: 2277: 2267: 2266: 2255: 2252: 2246: 2243: 2240: 2234: 2231: 2228: 2225: 2222: 2219: 2216: 2210: 2207: 2204: 2201: 2198: 2193: 2188: 2183: 2179: 2146: 2145: 2134: 2131: 2128: 2125: 2120: 2115: 2110: 2106: 2100: 2097: 2094: 2091: 2088: 2060: 2059: 2058: 2057: 2048: 2036: 2035: 2029: 2028: 2022: 2021: 2019: 2018: 2011: 2004: 1997: 1992: 1987: 1980: 1977:Distributivity 1973: 1966: 1958: 1955: 1954: 1948: 1947: 1946: 1945: 1940: 1917: 1904: 1891: 1878: 1865: 1852: 1832: 1831: 1825: 1824: 1818: 1817: 1808: 1805: 1793: 1790: 1787: 1784: 1781: 1776: 1771: 1766: 1762: 1759: 1756: 1753: 1750: 1747: 1742: 1737: 1732: 1728: 1725: 1719: 1716: 1713: 1710: 1707: 1704: 1701: 1698: 1695: 1692: 1687: 1682: 1677: 1673: 1660: 1659: 1648: 1645: 1642: 1639: 1634: 1629: 1624: 1620: 1614: 1611: 1608: 1605: 1602: 1599: 1594: 1589: 1584: 1580: 1566: 1565: 1554: 1551: 1548: 1545: 1542: 1537: 1532: 1527: 1523: 1517: 1514: 1511: 1508: 1505: 1500: 1495: 1490: 1486: 1480: 1474: 1471: 1468: 1465: 1462: 1459: 1454: 1449: 1444: 1440: 1434: 1431: 1428: 1425: 1422: 1417: 1412: 1407: 1403: 1397: 1375: 1374: 1363: 1360: 1357: 1354: 1351: 1346: 1341: 1336: 1332: 1326: 1323: 1320: 1317: 1314: 1309: 1304: 1299: 1295: 1289: 1267: 1266: 1255: 1252: 1249: 1246: 1243: 1238: 1233: 1228: 1224: 1202: 1201: 1190: 1187: 1184: 1181: 1176: 1171: 1166: 1162: 1148: 1147: 1135: 1132: 1129: 1126: 1121: 1116: 1111: 1107: 1101: 1083: 1082: 1071: 1068: 1065: 1062: 1057: 1052: 1047: 1043: 994: 982: 979: 977: 974: 961: 941: 920:Giuseppe Peano 916: 915: 903: 900: 897: 894: 891: 878:in the set of 867: 843: 840: 837: 834: 831: 828: 824: 819: 814: 810: 791:symbolic logic 786: 783: 767: 766: 754: 751: 748: 745: 742: 722: 702: 683: 682: 671: 668: 665: 662: 659: 639: 603: 600: 597: 594: 591: 571: 541: 538: 535: 532: 529: 509: 506: 503: 500: 497: 462: 459: 456: 453: 450: 430: 427: 424: 421: 418: 398: 395: 392: 389: 386: 375: 374: 362: 359: 356: 353: 350: 330: 310: 307: 203: 202: 191: 188: 185: 182: 179: 176: 166: 162: 161: 149: 129: 126: 123: 120: 100: 97: 94: 91: 88: 85: 75: 71: 70: 65: 61: 60: 55: 26: 9: 6: 4: 3: 2: 4826: 4815: 4812: 4810: 4809:Logic symbols 4807: 4806: 4804: 4791: 4790: 4785: 4777: 4771: 4768: 4766: 4763: 4761: 4758: 4756: 4753: 4749: 4746: 4745: 4744: 4741: 4739: 4736: 4734: 4731: 4729: 4725: 4722: 4720: 4717: 4715: 4712: 4710: 4707: 4705: 4702: 4701: 4699: 4695: 4689: 4686: 4684: 4681: 4679: 4678:Recursive set 4676: 4674: 4671: 4669: 4666: 4664: 4661: 4659: 4656: 4652: 4649: 4647: 4644: 4642: 4639: 4637: 4634: 4632: 4629: 4628: 4627: 4624: 4622: 4619: 4617: 4614: 4612: 4609: 4607: 4604: 4602: 4599: 4598: 4596: 4594: 4590: 4584: 4581: 4579: 4576: 4574: 4571: 4569: 4566: 4564: 4561: 4559: 4556: 4554: 4551: 4547: 4544: 4542: 4539: 4537: 4534: 4533: 4532: 4529: 4527: 4524: 4522: 4519: 4517: 4514: 4512: 4509: 4507: 4504: 4500: 4497: 4496: 4495: 4492: 4488: 4487:of arithmetic 4485: 4484: 4483: 4480: 4476: 4473: 4471: 4468: 4466: 4463: 4461: 4458: 4456: 4453: 4452: 4451: 4448: 4444: 4441: 4439: 4436: 4435: 4434: 4431: 4430: 4428: 4426: 4422: 4416: 4413: 4411: 4408: 4406: 4403: 4401: 4398: 4395: 4394:from ZFC 4391: 4388: 4386: 4383: 4377: 4374: 4373: 4372: 4369: 4367: 4364: 4362: 4359: 4358: 4357: 4354: 4352: 4349: 4347: 4344: 4342: 4339: 4337: 4334: 4332: 4329: 4327: 4324: 4323: 4321: 4319: 4315: 4305: 4304: 4300: 4299: 4294: 4293:non-Euclidean 4291: 4287: 4284: 4282: 4279: 4277: 4276: 4272: 4271: 4269: 4266: 4265: 4263: 4259: 4255: 4252: 4250: 4247: 4246: 4245: 4241: 4237: 4234: 4233: 4232: 4228: 4224: 4221: 4219: 4216: 4214: 4211: 4209: 4206: 4204: 4201: 4199: 4196: 4195: 4193: 4189: 4188: 4186: 4181: 4175: 4170:Example  4167: 4159: 4154: 4153: 4152: 4149: 4147: 4144: 4140: 4137: 4135: 4132: 4130: 4127: 4125: 4122: 4121: 4120: 4117: 4115: 4112: 4110: 4107: 4105: 4102: 4098: 4095: 4093: 4090: 4089: 4088: 4085: 4081: 4078: 4076: 4073: 4071: 4068: 4066: 4063: 4062: 4061: 4058: 4056: 4053: 4049: 4046: 4044: 4041: 4039: 4036: 4035: 4034: 4031: 4027: 4024: 4022: 4019: 4017: 4014: 4012: 4009: 4007: 4004: 4002: 3999: 3998: 3997: 3994: 3992: 3989: 3987: 3984: 3982: 3979: 3975: 3972: 3970: 3967: 3965: 3962: 3960: 3957: 3956: 3955: 3952: 3950: 3947: 3945: 3942: 3940: 3937: 3933: 3930: 3928: 3927:by definition 3925: 3924: 3923: 3920: 3916: 3913: 3912: 3911: 3908: 3906: 3903: 3901: 3898: 3896: 3893: 3891: 3888: 3887: 3884: 3881: 3879: 3875: 3870: 3864: 3860: 3850: 3847: 3845: 3842: 3840: 3837: 3835: 3832: 3830: 3827: 3825: 3822: 3820: 3817: 3815: 3814:Kripke–Platek 3812: 3810: 3807: 3803: 3800: 3798: 3795: 3794: 3793: 3790: 3789: 3787: 3783: 3775: 3772: 3771: 3770: 3767: 3765: 3762: 3758: 3755: 3754: 3753: 3750: 3748: 3745: 3743: 3740: 3738: 3735: 3733: 3730: 3727: 3723: 3719: 3716: 3712: 3709: 3707: 3704: 3702: 3699: 3698: 3697: 3693: 3690: 3689: 3687: 3685: 3681: 3677: 3669: 3666: 3664: 3661: 3659: 3658:constructible 3656: 3655: 3654: 3651: 3649: 3646: 3644: 3641: 3639: 3636: 3634: 3631: 3629: 3626: 3624: 3621: 3619: 3616: 3614: 3611: 3609: 3606: 3604: 3601: 3599: 3596: 3594: 3591: 3590: 3588: 3586: 3581: 3573: 3570: 3568: 3565: 3563: 3560: 3558: 3555: 3553: 3550: 3548: 3545: 3544: 3542: 3538: 3535: 3533: 3530: 3529: 3528: 3525: 3523: 3520: 3518: 3515: 3513: 3510: 3508: 3504: 3500: 3498: 3495: 3491: 3488: 3487: 3486: 3483: 3482: 3479: 3476: 3474: 3470: 3460: 3457: 3455: 3452: 3450: 3447: 3445: 3442: 3440: 3437: 3435: 3432: 3428: 3425: 3424: 3423: 3420: 3416: 3411: 3410: 3409: 3406: 3405: 3403: 3401: 3397: 3389: 3386: 3384: 3381: 3379: 3376: 3375: 3374: 3371: 3369: 3366: 3364: 3361: 3359: 3356: 3354: 3351: 3349: 3346: 3344: 3341: 3340: 3338: 3336: 3335:Propositional 3332: 3326: 3323: 3321: 3318: 3316: 3313: 3311: 3308: 3306: 3303: 3301: 3298: 3294: 3291: 3290: 3289: 3286: 3284: 3281: 3279: 3276: 3274: 3271: 3269: 3266: 3264: 3263:Logical truth 3261: 3259: 3256: 3255: 3253: 3251: 3247: 3244: 3242: 3238: 3232: 3229: 3227: 3224: 3222: 3219: 3217: 3214: 3212: 3209: 3207: 3203: 3199: 3195: 3193: 3190: 3188: 3185: 3183: 3179: 3176: 3175: 3173: 3171: 3165: 3160: 3154: 3151: 3149: 3146: 3144: 3141: 3139: 3136: 3134: 3131: 3129: 3126: 3124: 3121: 3119: 3116: 3114: 3111: 3109: 3106: 3104: 3101: 3099: 3096: 3092: 3089: 3088: 3087: 3084: 3083: 3081: 3077: 3073: 3066: 3061: 3059: 3054: 3052: 3047: 3046: 3043: 3033: 3028: 3022: 3010: 3001: 2997: 2992: 2989: 2985: 2980: 2977: 2971: 2966: 2963: 2957: 2952: 2949: 2948:contradiction 2944: 2940: 2935: 2932: 2927: 2923: 2918: 2914: 2907: 2902: 2898: 2891: 2886: 2883: 2879: 2874: 2871: 2867: 2862: 2857: 2852: 2849: 2844: 2840: 2835: 2832: 2828: 2823: 2820: 2816: 2811: 2806: 2801: 2798: 2794: 2789: 2786: 2782: 2777: 2772: 2767: 2766: 2761: 2757: 2749: 2744: 2742: 2737: 2735: 2730: 2729: 2726: 2717: 2715:1-56881-262-0 2711: 2707: 2702: 2701: 2689: 2685: 2684:0-387-97710-4 2681: 2677: 2673: 2668: 2660: 2654: 2650: 2646: 2642: 2641: 2633: 2625: 2619: 2616:. MIT Press. 2615: 2614: 2606: 2592: 2588: 2582: 2568: 2564: 2558: 2550: 2544: 2540: 2533: 2529: 2520: 2517: 2515: 2512: 2509: 2506: 2504: 2501: 2499: 2496: 2494: 2491: 2489: 2486: 2485: 2479: 2477: 2476:right adjoint 2473: 2469: 2468:inverse image 2465: 2461: 2457: 2453: 2449: 2443: 2433: 2431: 2430:Vacuous truth 2427: 2423: 2419: 2415: 2411: 2395: 2387: 2383: 2364: 2358: 2350: 2345: 2330:The empty set 2327: 2325: 2321: 2317: 2313: 2309: 2293: 2281: 2275: 2250: 2238: 2226: 2220: 2202: 2196: 2186: 2181: 2170: 2169: 2168: 2166: 2162: 2158: 2154: 2150: 2129: 2123: 2113: 2108: 2092: 2086: 2079: 2078: 2077: 2075: 2074: 2069: 2067: 2056: 2055:instantiation 2052: 2049: 2047: 2046:instantiation 2043: 2040: 2039: 2038: 2037: 2034: 2031: 2030: 2027: 2024: 2023: 2017: 2012: 2010: 2005: 2003: 1998: 1996: 1995:Transposition 1993: 1991: 1988: 1986: 1981: 1979: 1974: 1972: 1970:Commutativity 1967: 1965: 1963:Associativity 1960: 1959: 1957: 1956: 1953: 1950: 1949: 1944: 1941: 1939: 1937: 1931: 1929: 1928:modus tollens 1923: 1918: 1916: 1910: 1905: 1903: 1897: 1892: 1890: 1884: 1879: 1877: 1871: 1866: 1864: 1858: 1853: 1851: 1848: 1845:elimination ( 1841: 1836: 1835: 1834: 1833: 1830: 1827: 1826: 1823: 1820: 1819: 1816: 1813: 1812: 1804: 1785: 1779: 1769: 1764: 1757: 1751: 1745: 1735: 1730: 1711: 1705: 1702: 1696: 1690: 1680: 1675: 1663: 1643: 1637: 1627: 1622: 1609: 1603: 1597: 1587: 1582: 1578: 1571: 1570: 1569: 1549: 1543: 1530: 1525: 1515: 1509: 1503: 1493: 1488: 1472: 1466: 1460: 1447: 1442: 1432: 1426: 1420: 1410: 1405: 1388: 1387: 1386: 1382: 1380: 1358: 1352: 1339: 1334: 1324: 1318: 1312: 1302: 1297: 1280: 1279: 1278: 1276: 1272: 1250: 1244: 1231: 1226: 1215: 1214: 1213: 1211: 1207: 1185: 1179: 1169: 1164: 1153: 1152: 1151: 1130: 1124: 1114: 1109: 1092: 1091: 1090: 1088: 1066: 1060: 1050: 1045: 1034: 1033: 1032: 1030: 1026: 1022: 1018: 1014: 1009: 973: 959: 939: 931: 927: 926: 921: 901: 898: 895: 892: 889: 881: 865: 857: 856: 855: 841: 838: 835: 832: 829: 826: 817: 812: 800: 796: 792: 782: 780: 776: 772: 752: 749: 746: 743: 740: 720: 700: 692: 691: 690: 688: 669: 666: 663: 660: 657: 637: 629: 628: 627: 625: 621: 617: 601: 598: 595: 592: 589: 569: 562: 557: 555: 539: 536: 533: 530: 527: 507: 504: 501: 498: 495: 487: 482: 480: 476: 460: 457: 454: 451: 448: 428: 425: 422: 419: 416: 396: 393: 390: 387: 384: 360: 357: 354: 351: 348: 328: 320: 319: 318: 316: 313:Consider the 306: 304: 296: 279: 274: 272: 268: 264: 258: 250: 243: 237: 233: 230: 226: 222: 218: 215:is a type of 214: 210: 186: 180: 177: 167: 163: 147: 124: 118: 111:is true when 95: 89: 86: 76: 72: 69: 66: 62: 59: 56: 52: 44: 37: 33: 19: 4780: 4578:Ultraproduct 4425:Model theory 4390:Independence 4326:Formal proof 4318:Proof theory 4301: 4274: 4231:real numbers 4203:second-order 4114:Substitution 4064: 3991:Metalanguage 3932:conservative 3905:Axiom schema 3849:Constructive 3819:Morse–Kelley 3785:Set theories 3764:Aleph number 3757:inaccessible 3663:Grothendieck 3547:intersection 3434:Higher-order 3422:Second-order 3368:Truth tables 3325:Venn diagram 3108:Formal proof 2910: 2905: 2860: 2809: 2775: 2705: 2687: 2675: 2667: 2639: 2632: 2613:Logic Primer 2612: 2605: 2594:. Retrieved 2590: 2581: 2570:. Retrieved 2566: 2557: 2538: 2532: 2456:left adjoint 2445: 2425: 2421: 2417: 2413: 2408:denotes the 2385: 2381: 2334:The formula 2333: 2323: 2319: 2315: 2311: 2307: 2268: 2164: 2160: 2156: 2147: 2071: 2070: 2063: 2053: / 2044: / 1935: 1932: / 1927: 1924: / 1911: / 1908:Constructive 1898: / 1885: / 1872: / 1859: / 1847:modus ponens 1846: 1842: / 1664: 1661: 1567: 1383: 1376: 1268: 1209: 1205: 1203: 1149: 1086: 1084: 1028: 1024: 1020: 1016: 1012: 1010: 984: 923: 917: 788: 768: 684: 619: 558: 485: 483: 479:real numbers 376: 312: 291:THERE EXISTS 275: 270: 266: 256: 248: 241: 235: 212: 206: 18:There exists 4688:Type theory 4636:undecidable 4568:Truth value 4455:equivalence 4134:non-logical 3747:Enumeration 3737:Isomorphism 3684:cardinality 3668:Von Neumann 3633:Ultrafilter 3598:Uncountable 3532:equivalence 3449:Quantifiers 3439:Fixed-point 3408:First-order 3288:Consistency 3273:Proposition 3250:Traditional 3221:Lindström's 3211:Compactness 3153:Type theory 3098:Cardinality 2911:existential 2008:Exportation 1895:Disjunctive 1888:elimination 1875:elimination 1862:elimination 733:is odd and 561:even number 225:interpreted 4803:Categories 4499:elementary 4192:arithmetic 4060:Quantifier 4038:functional 3910:Expression 3628:Transitive 3572:identities 3557:complement 3490:hereditary 3473:Set theory 2697:References 2623:0262303965 2596:2020-09-04 2572:2020-09-04 2464:power sets 2436:As adjoint 1921:Absorption 976:Properties 882:such that 799:sans-serif 217:quantifier 58:Quantifier 4770:Supertask 4673:Recursion 4631:decidable 4465:saturated 4443:of models 4366:deductive 4361:axiomatic 4281:Hilbert's 4268:Euclidean 4249:canonical 4172:axiomatic 4104:Signature 4033:Predicate 3922:Extension 3844:Ackermann 3769:Operation 3648:Universal 3638:Recursive 3613:Singleton 3608:Inhabited 3593:Countable 3583:Types of 3567:power set 3537:partition 3454:Predicate 3400:Predicate 3315:Syllogism 3305:Soundness 3278:Inference 3268:Tautology 3170:paradoxes 2988:therefore 2976:therefore 2931:tautology 2895:universal 2688:See p. 58 2412:, and no 2410:empty set 2396:∅ 2355:∅ 2351:∈ 2342:∃ 2288:→ 2245:→ 2233:→ 2209:→ 2187:∈ 2178:∃ 2163:in which 2114:∈ 2105:∃ 2099:→ 2015:Tautology 1770:∈ 1761:∃ 1758:∨ 1736:∈ 1727:∃ 1718:→ 1703:∨ 1681:∈ 1672:∃ 1628:∈ 1619:∃ 1613:¬ 1610:≡ 1588:∈ 1579:∄ 1541:¬ 1531:∈ 1522:∃ 1516:≡ 1494:∈ 1485:∀ 1479:¬ 1458:¬ 1448:∈ 1439:∀ 1433:≡ 1411:∈ 1402:∃ 1396:¬ 1350:¬ 1340:∈ 1331:∀ 1325:≡ 1303:∈ 1294:∃ 1288:¬ 1242:¬ 1232:∈ 1223:∀ 1170:∈ 1161:∃ 1115:∈ 1106:∃ 1100:¬ 1051:∈ 1042:∃ 993:¬ 960:∪ 940:∩ 893:× 833:× 818:∈ 809:∃ 744:× 661:× 593:× 531:× 499:× 452:× 420:× 388:× 352:× 317:sentence 297:, and as 223:which is 175:∃ 84:∃ 74:Statement 36:Yo (kana) 4755:Logicism 4748:timeline 4724:Concrete 4583:Validity 4553:T-schema 4546:Kripke's 4541:Tarski's 4536:semantic 4526:Strength 4475:submodel 4470:spectrum 4438:function 4286:Tarski's 4275:Elements 4262:geometry 4218:Robinson 4139:variable 4124:function 4097:spectrum 4087:Sentence 4043:variable 3986:Language 3939:Relation 3900:Automata 3890:Alphabet 3874:language 3728:-jection 3706:codomain 3692:Function 3653:Universe 3623:Infinite 3527:Relation 3310:Validity 3300:Argument 3198:theorem, 2974:entails, 2960:entails, 2848:superset 2482:See also 2462:between 1473:≢ 981:Negation 785:Notation 554:solution 288:∃ 4697:Related 4494:Diagram 4392: ( 4371:Hilbert 4356:Systems 4351:Theorem 4229:of the 4174:systems 3954:Formula 3949:Grammar 3865: ( 3809:General 3522:Forcing 3507:Element 3427:Monadic 3202:paradox 3143:Theorem 3079:General 3000:because 2864:  2843:implies 2831:implies 2813:  2779:  2754:Common 2474:is the 2460:functor 797:" in a 299:\exists 295:Unicode 4460:finite 4223:Skolem 4176:  4151:Theory 4119:Symbol 4109:String 4092:atomic 3969:ground 3964:closed 3959:atomic 3915:ground 3878:syntax 3774:binary 3701:domain 3618:Finite 3383:finite 3241:Logics 3200:  3148:Theory 2962:proves 2858:  2807:  2773:  2712:  2682:  2655:  2620:  2545:  2466:, the 2291:  2248:  2236:  2212:  2102:  1721:  1616:  1519:  1482:  1476:  1436:  1399:  1328:  1291:  1103:  996:  315:formal 309:Basics 285: 283:U+2203 253:" or " 245:" or " 232:symbol 4450:Model 4198:Peano 4055:Proof 3895:Arity 3824:Naive 3711:image 3643:Fuzzy 3603:Empty 3552:union 3497:Class 3138:Model 3128:Lemma 3086:Axiom 2943:false 2781:& 2525:Notes 2458:of a 441:, or 409:, or 303:LaTeX 211:, an 64:Field 4573:Type 4376:list 4180:list 4157:list 4146:Term 4080:rank 3974:open 3868:list 3680:Maps 3585:sets 3444:Free 3414:list 3164:list 3091:list 2926:true 2882:nand 2710:ISBN 2680:ISBN 2653:ISBN 2618:ISBN 2543:ISBN 952:and 769:The 219:, a 54:Type 4260:of 4242:of 4190:of 3722:Sur 3696:Map 3503:Ur- 3485:Set 2870:iff 2819:not 2785:and 2645:doi 2446:In 922:in 789:In 685:is 481:.) 301:in 293:in 267:all 207:In 4805:: 4646:NP 4270:: 4264:: 4194:: 3871:), 3726:Bi 3718:In 2861:or 2810:or 2797:or 2776:or 2686:. 2651:. 2589:. 2565:. 2478:. 2064:A 1208:, 902:25 842:25 753:25 713:, 670:25 650:, 602:25 582:, 540:25 508:25 461:25 429:25 397:25 361:25 341:, 259:)" 255:(∃ 247:∃( 238:(" 4726:/ 4641:P 4396:) 4182:) 4178:( 4075:∀ 4070:! 4065:∃ 4026:= 4021:↔ 4016:→ 4011:∧ 4006:∨ 4001:¬ 3724:/ 3720:/ 3694:/ 3505:) 3501:( 3388:∞ 3378:3 3166:) 3064:e 3057:t 3050:v 2996:∵ 2984:∴ 2970:⊨ 2956:⊢ 2945:, 2939:⊥ 2928:, 2922:⊤ 2906:∃ 2890:∀ 2878:| 2866:≡ 2856:↔ 2845:, 2839:⊃ 2827:→ 2815:~ 2805:¬ 2793:∨ 2771:∧ 2747:e 2740:t 2733:v 2718:. 2690:. 2661:. 2647:: 2626:. 2599:. 2575:. 2551:. 2426:x 2424:( 2422:P 2418:x 2414:x 2386:x 2384:( 2382:P 2368:) 2365:x 2362:( 2359:P 2346:x 2324:c 2322:( 2320:P 2316:c 2312:X 2308:c 2294:Q 2285:) 2282:c 2279:( 2276:P 2254:) 2251:Q 2242:) 2239:Q 2230:) 2227:c 2224:( 2221:P 2218:( 2215:( 2206:) 2203:x 2200:( 2197:P 2192:X 2182:x 2165:c 2161:Q 2157:c 2133:) 2130:x 2127:( 2124:P 2119:X 2109:x 2096:) 2093:a 2090:( 2087:P 1849:) 1792:) 1789:) 1786:x 1783:( 1780:Q 1775:X 1765:x 1755:) 1752:x 1749:( 1746:P 1741:X 1731:x 1724:( 1715:) 1712:x 1709:( 1706:Q 1700:) 1697:x 1694:( 1691:P 1686:X 1676:x 1647:) 1644:x 1641:( 1638:P 1633:X 1623:x 1607:) 1604:x 1601:( 1598:P 1593:X 1583:x 1553:) 1550:x 1547:( 1544:P 1536:X 1526:x 1513:) 1510:x 1507:( 1504:P 1499:X 1489:x 1470:) 1467:x 1464:( 1461:P 1453:X 1443:x 1430:) 1427:x 1424:( 1421:P 1416:X 1406:x 1362:) 1359:x 1356:( 1353:P 1345:X 1335:x 1322:) 1319:x 1316:( 1313:P 1308:X 1298:x 1254:) 1251:x 1248:( 1245:P 1237:X 1227:x 1210:x 1206:x 1189:) 1186:x 1183:( 1180:P 1175:X 1165:x 1146:. 1134:) 1131:x 1128:( 1125:P 1120:X 1110:x 1087:x 1070:) 1067:x 1064:( 1061:P 1056:X 1046:x 1029:x 1025:X 1021:x 1017:x 1015:( 1013:P 914:. 899:= 896:n 890:n 866:n 839:= 836:n 830:n 827:: 823:N 813:n 795:E 765:. 750:= 747:n 741:n 721:n 701:n 667:= 664:n 658:n 638:n 620:n 599:= 596:n 590:n 570:n 537:= 534:n 528:n 505:= 502:5 496:5 486:n 458:= 455:2 449:2 426:= 423:1 417:1 394:= 391:0 385:0 373:. 358:= 355:n 349:n 329:n 257:x 251:) 249:x 242:x 240:∃ 190:) 187:x 184:( 181:P 178:x 160:. 148:x 128:) 125:x 122:( 119:P 99:) 96:x 93:( 90:P 87:x 45:. 38:. 32:Ǝ 20:)

Index

There exists
Ǝ
Yo (kana)
K41 (nightclub)
Quantifier
Mathematical logic
predicate logic
quantifier
logical constant
interpreted
logical operator
symbol
universal quantification
quantification (logic)
Unicode
LaTeX
formal
domain of discourse
real numbers
solution
even number
domain of discourse
Logical conjunctions
logically equivalent
mathematical proof
constructive proof
nonconstructive proof
symbolic logic
E
sans-serif

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