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Existential quantification

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2140:, 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 4773: 3016: 3005: 1552: 1791: 1380: 1361: 1646: 2065:(∃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, 2253: 1547:{\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)} 1656: 2132: 1373:
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
541:" is true only for that single natural number, 5; the existence of a single 4566: 4413: 4314: 4306: 4186: 4134: 4043: 3979: 3962: 3893: 3752: 3611: 3313: 3096: 2867: 2785: 2781: 2444: 1902: 1832: 303: 2144:, as long as it does not contain the name. Symbolically, for an arbitrary 4676: 4556: 3735: 3725: 3672: 3356: 3276: 3261: 3141: 3086: 2712: 549: 467: 1020:
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
2443:, the existential quantifier can be understood as the 2383: 2329: 2263: 2165: 2074: 1659: 1566: 1383: 1275: 1210: 1148: 1087: 1029: 980: 947: 927: 877: 853: 796: 783: 728: 708: 688: 645: 625: 603:" is false, because there are no even solutions. The 577: 557: 515: 483: 436: 404: 372: 336: 316: 162: 135: 106: 71: 2362:{\displaystyle \exists {x}{\in }\varnothing \,P(x)} 1193:is logically equivalent to "For any natural number 1183:{\displaystyle \exists {x}{\in }\mathbf {X} \,P(x)} 1064:{\displaystyle \exists {x}{\in }\mathbf {X} \,P(x)} 2459:functor of a function between sets; likewise, the 2389: 2361: 2287: 2247: 2126: 1785: 1640: 1546: 1355: 1247: 1182: 1127: 1063: 989: 953: 933: 895: 859: 835: 746: 714: 694: 663: 631: 595: 563: 533: 501: 454: 422: 390: 354: 322: 183: 141: 121: 92: 1909: 466:to be the natural numbers, not, for example, the 258:members of the domain. Some sources use the term 19:"∃" redirects here. For the letter turned E, see 4789: 1989: 1958: 1850: 250:). Existential quantification is distinct from 3045: 2728: 2003: 1972: 1870: 1863: 907:The symbol's first usage is thought to be by 2625: 1201:is not greater than 0 and less than 1", or: 269:. The existential quantifier is encoded as 3237: 3052: 3038: 2742: 2735: 2721: 2692: 2431:Universal quantification § As adjoint 607:, which specifies the values the variable 2598: 2346: 2184: 2111: 1767: 1733: 1678: 1625: 1585: 1528: 1491: 1445: 1408: 1337: 1300: 1229: 1167: 1112: 1048: 811: 2525: 262:to refer to existential quantification. 2619: 4790: 3059: 2303:; else, the logic does not follow: If 3033: 2716: 2417:) – exist in the empty set. See also 1795: 2599:Allen, Colin; Hand, Michael (2001). 2632:. Springer Cham. pp. 210–211. 1262:'s existential quantification is a 1258:Generally, then, the negation of a 997:symbol is used to denote negation. 13: 2695:Fundamentals of Mathematical Logic 2405:of any description – let alone an 2330: 2166: 2093: 1749: 1715: 1660: 1607: 1601: 1529: 1510: 1473: 1467: 1446: 1427: 1390: 1384: 1338: 1319: 1282: 1276: 1230: 1211: 1149: 1094: 1088: 1030: 981: 797: 163: 129:is true for at least one value of 72: 16:Mathematical use of "there exists" 14: 4814: 2343: 4771: 3014: 3003: 2318: 2180: 2107: 1763: 1729: 1674: 1621: 1581: 1524: 1487: 1441: 1404: 1333: 1296: 1225: 1163: 1108: 1044: 843:represents the (true) statement 477:, we produce the true statement 2369:is always false, regardless of 2295:must be true for all values of 23:. For the Japanese kana ヨ, see 2654: 2592: 2568: 2544: 2519: 2356: 2350: 2276: 2273: 2267: 2242: 2233: 2230: 2221: 2218: 2212: 2206: 2203: 2197: 2194: 2188: 2121: 2115: 2087: 2084: 2078: 1780: 1777: 1771: 1743: 1737: 1712: 1706: 1703: 1697: 1688: 1682: 1635: 1629: 1595: 1589: 1541: 1535: 1501: 1495: 1458: 1452: 1418: 1412: 1350: 1344: 1310: 1304: 1242: 1236: 1177: 1171: 1122: 1116: 1058: 1052: 178: 172: 116: 110: 87: 81: 1: 4732:History of mathematical logic 2685: 2665:Sheaves in Geometry and Logic 2424: 2409:fulfilling a given predicate 1366:(This is a generalization of 964: 619:For some positive odd number 294:and related formula editors. 184:{\displaystyle \exists xP(x)} 93:{\displaystyle \exists xP(x)} 4657:Primitive recursive function 2552:"Predicates and Quantifiers" 2390:{\displaystyle \varnothing } 896:{\displaystyle n\times n=25} 747:{\displaystyle n\times n=25} 664:{\displaystyle n\times n=25} 596:{\displaystyle n\times n=25} 534:{\displaystyle n\times n=25} 502:{\displaystyle 5\times 5=25} 455:{\displaystyle 2\times 2=25} 423:{\displaystyle 1\times 1=25} 391:{\displaystyle 0\times 0=25} 355:{\displaystyle n\times n=25} 7: 2470: 2288:{\displaystyle P(c)\to \ Q} 969: 773: 509:. It does not matter that " 10: 4819: 3721:Schröder–Bernstein theorem 3448:Monadic predicate calculus 3107:Foundations of mathematics 2499:– for the unicode symbol ∃ 2428: 2040:Existential generalization 1845:Biconditional introduction 202:existential quantification 38:Existential quantification 29: 18: 4767: 4754:Philosophy of mathematics 4703:Automated theorem proving 4685: 4580: 4412: 4305: 4157: 3874: 3850: 3828:Von Neumann–Bernays–Gödel 3773: 3667: 3571: 3469: 3460: 3387: 3322: 3228: 3150: 3067: 3000: 2751: 2663:, Ieke Moerdijk, (1992): 2638:10.1007/978-3-319-71350-2 2526:Bergmann, Merrie (2014). 2508:Uniqueness quantification 2138:Existential instantiation 297: 153: 62: 52: 42: 2513: 2062:Existential introduction 2031:Universal generalization 1871:Disjunction introduction 1858:Conjunction introduction 1828:Implication introduction 1264:universal quantification 990:{\displaystyle \lnot \ } 782:, "∃" (a turned letter " 682:For some natural number 310:For some natural number 252:universal quantification 4404:Self-verifying theories 4225:Tarski's axiomatization 3176:Tarski's undefinability 3171:incompleteness theorems 548:In contrast, "For some 4778:Mathematics portal 4389:Proof of impossibility 4037:propositional variable 3347:Propositional calculus 3021:Mathematics portal 2421:for more information. 2391: 2363: 2289: 2249: 2148:and for a proposition 2128: 1890:hypothetical syllogism 1811:Propositional calculus 1787: 1642: 1548: 1357: 1260:propositional function 1249: 1184: 1129: 1065: 991: 955: 935: 914:Formulario mathematico 897: 861: 837: 748: 716: 696: 665: 633: 597: 565: 535: 503: 456: 424: 392: 356: 324: 267:quantification (logic) 225:existential quantifier 185: 143: 123: 94: 4647:Kolmogorov complexity 4600:Computably enumerable 4500:Model complete theory 4292:Principia Mathematica 3352:Propositional formula 3181:Banach–Tarski paradox 3010:Philosophy portal 2626:Stephen Webb (2018). 2497:List of logic symbols 2392: 2364: 2299:over the same domain 2290: 2250: 2129: 1932:Negation introduction 1925:modus ponendo tollens 1788: 1643: 1549: 1370:to predicate logic.) 1358: 1250: 1185: 1130: 1066: 992: 956: 954:{\displaystyle \cup } 936: 934:{\displaystyle \cap } 898: 862: 838: 768:nonconstructive proof 749: 717: 697: 666: 634: 598: 566: 536: 504: 457: 425: 393: 357: 325: 186: 144: 124: 95: 4595:Church–Turing thesis 4582:Computability theory 3791:continuum hypothesis 3309:Square of opposition 3167:Gödel's completeness 2492:Lindström quantifier 2461:universal quantifier 2381: 2327: 2261: 2163: 2072: 1990:Material implication 1941:Rules of replacement 1804:Transformation rules 1657: 1564: 1381: 1273: 1208: 1146: 1085: 1027: 1008:) is the predicate " 978: 945: 925: 917:(1896). Afterwards, 875: 851: 794: 726: 706: 686: 676:logically equivalent 643: 623: 613:Logical conjunctions 575: 555: 513: 481: 434: 402: 370: 334: 314: 160: 133: 122:{\displaystyle P(x)} 104: 69: 4749:Mathematical object 4640:P versus NP problem 4605:Computable function 4399:Reverse mathematics 4325:Logical consequence 4202:primitive recursive 4197:elementary function 3970:Free/bound variable 3823:Tarski–Grothendieck 3342:Logical connectives 3272:Logical equivalence 3122:Logical consequence 2693:Hinman, P. (2005). 2503:Quantifier variance 2377:). This is because 1903:destructive dilemma 605:domain of discourse 464:domain of discourse 39: 4803:Quantifier (logic) 4547:Transfer principle 4510:Semantics of logic 4495:Categorical theory 4471:Non-standard model 3985:Logical connective 3112:Information theory 3061:Mathematical logic 2477:Existential clause 2439:and the theory of 2387: 2359: 2285: 2245: 2124: 2022:Rules of inference 1818:Rules of inference 1796:Rules of inference 1783: 1638: 1544: 1353: 1245: 1180: 1125: 1061: 987: 951: 931: 893: 857: 847:There exists some 833: 764:constructive proof 760:mathematical proof 744: 712: 692: 661: 629: 593: 561: 531: 499: 452: 420: 388: 352: 320: 260:existentialization 181: 154:Symbolic statement 139: 119: 90: 57:Mathematical logic 37: 4785: 4784: 4717:Abstract category 4520:Theories of truth 4330:Rule of inference 4320:Natural deduction 4301: 4300: 3846: 3845: 3551:Cartesian product 3456: 3455: 3362:Many-valued logic 3337:Boolean functions 3220:Russell's paradox 3195:diagonal argument 3092:First-order logic 3027: 3026: 2995: 2994: 2661:Saunders Mac Lane 2647:978-3-319-71349-6 2576:"1.2 Quantifiers" 2537:978-0-07-803841-9 2487:First-order logic 2482:Existence theorem 2281: 2238: 2226: 2202: 2156:does not appear: 2092: 2055:rule of inference 2051: 2050: 1711: 1606: 1509: 1472: 1466: 1426: 1389: 1318: 1281: 1093: 986: 860:{\displaystyle n} 715:{\displaystyle n} 695:{\displaystyle n} 632:{\displaystyle n} 564:{\displaystyle n} 323:{\displaystyle n} 194: 193: 142:{\displaystyle x} 4810: 4776: 4775: 4727:History of logic 4722:Category of sets 4615:Decision problem 4394:Ordinal analysis 4335:Sequent calculus 4233:Boolean algebras 4173: 4172: 4147: 4118:logical/constant 3872: 3871: 3858: 3781:Zermelo–Fraenkel 3532:Set operations: 3467: 3466: 3404: 3235: 3234: 3215:Löwenheim–Skolem 3102:Formal semantics 3054: 3047: 3040: 3031: 3030: 3019: 3018: 3008: 3007: 3006: 2938: 2887: 2767: 2754: 2753: 2737: 2730: 2723: 2714: 2713: 2708: 2680: 2667:Springer-Verlag 2658: 2652: 2651: 2629:Clash of Symbols 2623: 2617: 2616: 2596: 2590: 2589: 2587: 2586: 2572: 2566: 2565: 2563: 2562: 2556:www.csm.ornl.gov 2548: 2542: 2541: 2523: 2441:elementary topoi 2396: 2394: 2393: 2388: 2368: 2366: 2365: 2360: 2342: 2337: 2294: 2292: 2291: 2286: 2279: 2254: 2252: 2251: 2246: 2236: 2224: 2200: 2183: 2178: 2173: 2142:necessarily true 2133: 2131: 2130: 2125: 2110: 2105: 2100: 2090: 2005: 1998: 1991: 1979:De Morgan's laws 1974: 1967: 1960: 1953: 1927: 1919: 1911: 1904: 1898: 1891: 1885: 1878: 1872: 1865: 1859: 1852: 1846: 1839: 1829: 1800: 1799: 1792: 1790: 1789: 1784: 1766: 1761: 1756: 1732: 1727: 1722: 1709: 1677: 1672: 1667: 1647: 1645: 1644: 1639: 1624: 1619: 1614: 1604: 1584: 1579: 1574: 1553: 1551: 1550: 1545: 1527: 1522: 1517: 1507: 1490: 1485: 1480: 1470: 1464: 1444: 1439: 1434: 1424: 1407: 1402: 1397: 1387: 1368:De Morgan's laws 1362: 1360: 1359: 1354: 1336: 1331: 1326: 1316: 1299: 1294: 1289: 1279: 1254: 1252: 1251: 1246: 1228: 1223: 1218: 1189: 1187: 1186: 1181: 1166: 1161: 1156: 1134: 1132: 1131: 1126: 1111: 1106: 1101: 1091: 1070: 1068: 1067: 1062: 1047: 1042: 1037: 1000:For example, if 996: 994: 993: 988: 984: 960: 958: 957: 952: 940: 938: 937: 932: 919:Bertrand Russell 902: 900: 899: 894: 866: 864: 863: 858: 842: 840: 839: 834: 814: 809: 804: 753: 751: 750: 745: 721: 719: 718: 713: 701: 699: 698: 693: 678:to the sentence 670: 668: 667: 662: 638: 636: 635: 630: 602: 600: 599: 594: 570: 568: 567: 562: 540: 538: 537: 532: 508: 506: 505: 500: 461: 459: 458: 453: 429: 427: 426: 421: 397: 395: 394: 389: 361: 359: 358: 353: 329: 327: 326: 321: 289: 281: 278: 275: 273: 249: 241: 233: 218:logical operator 210:logical constant 190: 188: 187: 182: 148: 146: 145: 140: 128: 126: 125: 120: 99: 97: 96: 91: 40: 36: 4818: 4817: 4813: 4812: 4811: 4809: 4808: 4807: 4788: 4787: 4786: 4781: 4770: 4763: 4708:Category theory 4698:Algebraic logic 4681: 4652:Lambda calculus 4590:Church encoding 4576: 4552:Truth predicate 4408: 4374:Complete theory 4297: 4166: 4162: 4158: 4153: 4145: 3865: and  3861: 3856: 3842: 3818:New Foundations 3786:axiom of choice 3769: 3731:Gödel numbering 3671: and  3663: 3567: 3452: 3402: 3383: 3332:Boolean algebra 3318: 3282:Equiconsistency 3247:Classical logic 3224: 3205:Halting problem 3193: and  3169: and  3157: and  3156: 3151:Theorems ( 3146: 3063: 3058: 3028: 3023: 3013: 3012: 3004: 3002: 2996: 2991: 2990: 2987: 2983: 2975: 2974: 2971: 2967: 2959: 2955: 2947: 2943: 2934: 2925: 2921: 2916: 2908: 2904: 2896: 2892: 2883: 2874: 2870: 2862: 2858: 2850: 2846: 2838: 2835: 2832: 2824: 2821: 2818: 2810: 2806: 2801: 2793: 2789: 2784: 2776: 2772: 2763: 2747: 2745:logical symbols 2741: 2711: 2705: 2688: 2683: 2659: 2655: 2648: 2624: 2620: 2613: 2597: 2593: 2584: 2582: 2580:www.whitman.edu 2574: 2573: 2569: 2560: 2558: 2550: 2549: 2545: 2538: 2530:. McGraw Hill. 2524: 2520: 2516: 2473: 2437:category theory 2433: 2427: 2382: 2379: 2378: 2338: 2333: 2328: 2325: 2324: 2321: 2262: 2259: 2258: 2179: 2174: 2169: 2164: 2161: 2160: 2106: 2101: 2096: 2073: 2070: 2069: 2015:Predicate logic 2009: 1973:Double negation 1827: 1798: 1762: 1757: 1752: 1728: 1723: 1718: 1673: 1668: 1663: 1658: 1655: 1654: 1620: 1615: 1610: 1580: 1575: 1570: 1565: 1562: 1561: 1523: 1518: 1513: 1486: 1481: 1476: 1440: 1435: 1430: 1403: 1398: 1393: 1382: 1379: 1378: 1332: 1327: 1322: 1295: 1290: 1285: 1274: 1271: 1270: 1224: 1219: 1214: 1209: 1206: 1205: 1162: 1157: 1152: 1147: 1144: 1143: 1107: 1102: 1097: 1086: 1083: 1082: 1043: 1038: 1033: 1028: 1025: 1024: 979: 976: 975: 972: 967: 946: 943: 942: 926: 923: 922: 876: 873: 872: 869:natural numbers 852: 849: 848: 810: 805: 800: 795: 792: 791: 776: 727: 724: 723: 707: 704: 703: 687: 684: 683: 644: 641: 640: 624: 621: 620: 576: 573: 572: 556: 553: 552: 514: 511: 510: 482: 479: 478: 435: 432: 431: 403: 400: 399: 371: 368: 367: 335: 332: 331: 315: 312: 311: 300: 287: 279: 276: 271: 270: 243: 235: 228: 198:predicate logic 161: 158: 157: 134: 131: 130: 105: 102: 101: 70: 67: 66: 35: 32:K41 (nightclub) 28: 17: 12: 11: 5: 4816: 4806: 4805: 4800: 4783: 4782: 4768: 4765: 4764: 4762: 4761: 4756: 4751: 4746: 4741: 4740: 4739: 4729: 4724: 4719: 4710: 4705: 4700: 4695: 4693:Abstract logic 4689: 4687: 4683: 4682: 4680: 4679: 4674: 4672:Turing machine 4669: 4664: 4659: 4654: 4649: 4644: 4643: 4642: 4637: 4632: 4627: 4622: 4612: 4610:Computable set 4607: 4602: 4597: 4592: 4586: 4584: 4578: 4577: 4575: 4574: 4569: 4564: 4559: 4554: 4549: 4544: 4539: 4538: 4537: 4532: 4527: 4517: 4512: 4507: 4505:Satisfiability 4502: 4497: 4492: 4491: 4490: 4480: 4479: 4478: 4468: 4467: 4466: 4461: 4456: 4451: 4446: 4436: 4435: 4434: 4429: 4422:Interpretation 4418: 4416: 4410: 4409: 4407: 4406: 4401: 4396: 4391: 4386: 4376: 4371: 4370: 4369: 4368: 4367: 4357: 4352: 4342: 4337: 4332: 4327: 4322: 4317: 4311: 4309: 4303: 4302: 4299: 4298: 4296: 4295: 4287: 4286: 4285: 4284: 4279: 4278: 4277: 4272: 4267: 4247: 4246: 4245: 4243:minimal axioms 4240: 4229: 4228: 4227: 4216: 4215: 4214: 4209: 4204: 4199: 4194: 4189: 4176: 4174: 4155: 4154: 4152: 4151: 4150: 4149: 4137: 4132: 4131: 4130: 4125: 4120: 4115: 4105: 4100: 4095: 4090: 4089: 4088: 4083: 4073: 4072: 4071: 4066: 4061: 4056: 4046: 4041: 4040: 4039: 4034: 4029: 4019: 4018: 4017: 4012: 4007: 4002: 3997: 3992: 3982: 3977: 3972: 3967: 3966: 3965: 3960: 3955: 3950: 3940: 3935: 3933:Formation rule 3930: 3925: 3924: 3923: 3918: 3908: 3907: 3906: 3896: 3891: 3886: 3881: 3875: 3869: 3852:Formal systems 3848: 3847: 3844: 3843: 3841: 3840: 3835: 3830: 3825: 3820: 3815: 3810: 3805: 3800: 3795: 3794: 3793: 3788: 3777: 3775: 3771: 3770: 3768: 3767: 3766: 3765: 3755: 3750: 3749: 3748: 3741:Large cardinal 3738: 3733: 3728: 3723: 3718: 3704: 3703: 3702: 3697: 3692: 3677: 3675: 3665: 3664: 3662: 3661: 3660: 3659: 3654: 3649: 3639: 3634: 3629: 3624: 3619: 3614: 3609: 3604: 3599: 3594: 3589: 3584: 3578: 3576: 3569: 3568: 3566: 3565: 3564: 3563: 3558: 3553: 3548: 3543: 3538: 3530: 3529: 3528: 3523: 3513: 3508: 3506:Extensionality 3503: 3501:Ordinal number 3498: 3488: 3483: 3482: 3481: 3470: 3464: 3458: 3457: 3454: 3453: 3451: 3450: 3445: 3440: 3435: 3430: 3425: 3420: 3419: 3418: 3408: 3407: 3406: 3393: 3391: 3385: 3384: 3382: 3381: 3380: 3379: 3374: 3369: 3359: 3354: 3349: 3344: 3339: 3334: 3328: 3326: 3320: 3319: 3317: 3316: 3311: 3306: 3301: 3296: 3291: 3286: 3285: 3284: 3274: 3269: 3264: 3259: 3254: 3249: 3243: 3241: 3232: 3226: 3225: 3223: 3222: 3217: 3212: 3207: 3202: 3197: 3185:Cantor's  3183: 3178: 3173: 3163: 3161: 3148: 3147: 3145: 3144: 3139: 3134: 3129: 3124: 3119: 3114: 3109: 3104: 3099: 3094: 3089: 3084: 3083: 3082: 3071: 3069: 3065: 3064: 3057: 3056: 3049: 3042: 3034: 3025: 3024: 3001: 2998: 2997: 2993: 2992: 2988:quantification 2984: 2979: 2978: 2976: 2972:quantification 2968: 2963: 2962: 2960: 2951: 2950: 2948: 2929: 2928: 2926: 2912: 2911: 2909: 2900: 2899: 2897: 2878: 2877: 2875: 2866: 2865: 2863: 2854: 2853: 2851: 2842: 2841: 2839: 2828: 2827: 2825: 2814: 2813: 2811: 2797: 2796: 2794: 2780: 2779: 2777: 2758: 2757: 2752: 2749: 2748: 2740: 2739: 2732: 2725: 2717: 2710: 2709: 2703: 2697:. A K Peters. 2689: 2687: 2684: 2682: 2681: 2653: 2646: 2618: 2611: 2591: 2567: 2543: 2536: 2528:The Logic Book 2517: 2515: 2512: 2511: 2510: 2505: 2500: 2494: 2489: 2484: 2479: 2472: 2469: 2429:Main article: 2426: 2423: 2386: 2358: 2355: 2352: 2349: 2345: 2341: 2336: 2332: 2320: 2317: 2284: 2278: 2275: 2272: 2269: 2266: 2256: 2255: 2244: 2241: 2235: 2232: 2229: 2223: 2220: 2217: 2214: 2211: 2208: 2205: 2199: 2196: 2193: 2190: 2187: 2182: 2177: 2172: 2168: 2135: 2134: 2123: 2120: 2117: 2114: 2109: 2104: 2099: 2095: 2089: 2086: 2083: 2080: 2077: 2049: 2048: 2047: 2046: 2037: 2025: 2024: 2018: 2017: 2011: 2010: 2008: 2007: 2000: 1993: 1986: 1981: 1976: 1969: 1966:Distributivity 1962: 1955: 1947: 1944: 1943: 1937: 1936: 1935: 1934: 1929: 1906: 1893: 1880: 1867: 1854: 1841: 1821: 1820: 1814: 1813: 1807: 1806: 1797: 1794: 1782: 1779: 1776: 1773: 1770: 1765: 1760: 1755: 1751: 1748: 1745: 1742: 1739: 1736: 1731: 1726: 1721: 1717: 1714: 1708: 1705: 1702: 1699: 1696: 1693: 1690: 1687: 1684: 1681: 1676: 1671: 1666: 1662: 1649: 1648: 1637: 1634: 1631: 1628: 1623: 1618: 1613: 1609: 1603: 1600: 1597: 1594: 1591: 1588: 1583: 1578: 1573: 1569: 1555: 1554: 1543: 1540: 1537: 1534: 1531: 1526: 1521: 1516: 1512: 1506: 1503: 1500: 1497: 1494: 1489: 1484: 1479: 1475: 1469: 1463: 1460: 1457: 1454: 1451: 1448: 1443: 1438: 1433: 1429: 1423: 1420: 1417: 1414: 1411: 1406: 1401: 1396: 1392: 1386: 1364: 1363: 1352: 1349: 1346: 1343: 1340: 1335: 1330: 1325: 1321: 1315: 1312: 1309: 1306: 1303: 1298: 1293: 1288: 1284: 1278: 1256: 1255: 1244: 1241: 1238: 1235: 1232: 1227: 1222: 1217: 1213: 1191: 1190: 1179: 1176: 1173: 1170: 1165: 1160: 1155: 1151: 1137: 1136: 1124: 1121: 1118: 1115: 1110: 1105: 1100: 1096: 1090: 1072: 1071: 1060: 1057: 1054: 1051: 1046: 1041: 1036: 1032: 983: 971: 968: 966: 963: 950: 930: 909:Giuseppe Peano 905: 904: 892: 889: 886: 883: 880: 867:in the set of 856: 832: 829: 826: 823: 820: 817: 813: 808: 803: 799: 780:symbolic logic 775: 772: 756: 755: 743: 740: 737: 734: 731: 711: 691: 672: 671: 660: 657: 654: 651: 648: 628: 592: 589: 586: 583: 580: 560: 530: 527: 524: 521: 518: 498: 495: 492: 489: 486: 451: 448: 445: 442: 439: 419: 416: 413: 410: 407: 387: 384: 381: 378: 375: 364: 363: 351: 348: 345: 342: 339: 319: 299: 296: 192: 191: 180: 177: 174: 171: 168: 165: 155: 151: 150: 138: 118: 115: 112: 109: 89: 86: 83: 80: 77: 74: 64: 60: 59: 54: 50: 49: 44: 15: 9: 6: 4: 3: 2: 4815: 4804: 4801: 4799: 4798:Logic symbols 4796: 4795: 4793: 4780: 4779: 4774: 4766: 4760: 4757: 4755: 4752: 4750: 4747: 4745: 4742: 4738: 4735: 4734: 4733: 4730: 4728: 4725: 4723: 4720: 4718: 4714: 4711: 4709: 4706: 4704: 4701: 4699: 4696: 4694: 4691: 4690: 4688: 4684: 4678: 4675: 4673: 4670: 4668: 4667:Recursive set 4665: 4663: 4660: 4658: 4655: 4653: 4650: 4648: 4645: 4641: 4638: 4636: 4633: 4631: 4628: 4626: 4623: 4621: 4618: 4617: 4616: 4613: 4611: 4608: 4606: 4603: 4601: 4598: 4596: 4593: 4591: 4588: 4587: 4585: 4583: 4579: 4573: 4570: 4568: 4565: 4563: 4560: 4558: 4555: 4553: 4550: 4548: 4545: 4543: 4540: 4536: 4533: 4531: 4528: 4526: 4523: 4522: 4521: 4518: 4516: 4513: 4511: 4508: 4506: 4503: 4501: 4498: 4496: 4493: 4489: 4486: 4485: 4484: 4481: 4477: 4476:of arithmetic 4474: 4473: 4472: 4469: 4465: 4462: 4460: 4457: 4455: 4452: 4450: 4447: 4445: 4442: 4441: 4440: 4437: 4433: 4430: 4428: 4425: 4424: 4423: 4420: 4419: 4417: 4415: 4411: 4405: 4402: 4400: 4397: 4395: 4392: 4390: 4387: 4384: 4383:from ZFC 4380: 4377: 4375: 4372: 4366: 4363: 4362: 4361: 4358: 4356: 4353: 4351: 4348: 4347: 4346: 4343: 4341: 4338: 4336: 4333: 4331: 4328: 4326: 4323: 4321: 4318: 4316: 4313: 4312: 4310: 4308: 4304: 4294: 4293: 4289: 4288: 4283: 4282:non-Euclidean 4280: 4276: 4273: 4271: 4268: 4266: 4265: 4261: 4260: 4258: 4255: 4254: 4252: 4248: 4244: 4241: 4239: 4236: 4235: 4234: 4230: 4226: 4223: 4222: 4221: 4217: 4213: 4210: 4208: 4205: 4203: 4200: 4198: 4195: 4193: 4190: 4188: 4185: 4184: 4182: 4178: 4177: 4175: 4170: 4164: 4159:Example  4156: 4148: 4143: 4142: 4141: 4138: 4136: 4133: 4129: 4126: 4124: 4121: 4119: 4116: 4114: 4111: 4110: 4109: 4106: 4104: 4101: 4099: 4096: 4094: 4091: 4087: 4084: 4082: 4079: 4078: 4077: 4074: 4070: 4067: 4065: 4062: 4060: 4057: 4055: 4052: 4051: 4050: 4047: 4045: 4042: 4038: 4035: 4033: 4030: 4028: 4025: 4024: 4023: 4020: 4016: 4013: 4011: 4008: 4006: 4003: 4001: 3998: 3996: 3993: 3991: 3988: 3987: 3986: 3983: 3981: 3978: 3976: 3973: 3971: 3968: 3964: 3961: 3959: 3956: 3954: 3951: 3949: 3946: 3945: 3944: 3941: 3939: 3936: 3934: 3931: 3929: 3926: 3922: 3919: 3917: 3916:by definition 3914: 3913: 3912: 3909: 3905: 3902: 3901: 3900: 3897: 3895: 3892: 3890: 3887: 3885: 3882: 3880: 3877: 3876: 3873: 3870: 3868: 3864: 3859: 3853: 3849: 3839: 3836: 3834: 3831: 3829: 3826: 3824: 3821: 3819: 3816: 3814: 3811: 3809: 3806: 3804: 3803:Kripke–Platek 3801: 3799: 3796: 3792: 3789: 3787: 3784: 3783: 3782: 3779: 3778: 3776: 3772: 3764: 3761: 3760: 3759: 3756: 3754: 3751: 3747: 3744: 3743: 3742: 3739: 3737: 3734: 3732: 3729: 3727: 3724: 3722: 3719: 3716: 3712: 3708: 3705: 3701: 3698: 3696: 3693: 3691: 3688: 3687: 3686: 3682: 3679: 3678: 3676: 3674: 3670: 3666: 3658: 3655: 3653: 3650: 3648: 3647:constructible 3645: 3644: 3643: 3640: 3638: 3635: 3633: 3630: 3628: 3625: 3623: 3620: 3618: 3615: 3613: 3610: 3608: 3605: 3603: 3600: 3598: 3595: 3593: 3590: 3588: 3585: 3583: 3580: 3579: 3577: 3575: 3570: 3562: 3559: 3557: 3554: 3552: 3549: 3547: 3544: 3542: 3539: 3537: 3534: 3533: 3531: 3527: 3524: 3522: 3519: 3518: 3517: 3514: 3512: 3509: 3507: 3504: 3502: 3499: 3497: 3493: 3489: 3487: 3484: 3480: 3477: 3476: 3475: 3472: 3471: 3468: 3465: 3463: 3459: 3449: 3446: 3444: 3441: 3439: 3436: 3434: 3431: 3429: 3426: 3424: 3421: 3417: 3414: 3413: 3412: 3409: 3405: 3400: 3399: 3398: 3395: 3394: 3392: 3390: 3386: 3378: 3375: 3373: 3370: 3368: 3365: 3364: 3363: 3360: 3358: 3355: 3353: 3350: 3348: 3345: 3343: 3340: 3338: 3335: 3333: 3330: 3329: 3327: 3325: 3324:Propositional 3321: 3315: 3312: 3310: 3307: 3305: 3302: 3300: 3297: 3295: 3292: 3290: 3287: 3283: 3280: 3279: 3278: 3275: 3273: 3270: 3268: 3265: 3263: 3260: 3258: 3255: 3253: 3252:Logical truth 3250: 3248: 3245: 3244: 3242: 3240: 3236: 3233: 3231: 3227: 3221: 3218: 3216: 3213: 3211: 3208: 3206: 3203: 3201: 3198: 3196: 3192: 3188: 3184: 3182: 3179: 3177: 3174: 3172: 3168: 3165: 3164: 3162: 3160: 3154: 3149: 3143: 3140: 3138: 3135: 3133: 3130: 3128: 3125: 3123: 3120: 3118: 3115: 3113: 3110: 3108: 3105: 3103: 3100: 3098: 3095: 3093: 3090: 3088: 3085: 3081: 3078: 3077: 3076: 3073: 3072: 3070: 3066: 3062: 3055: 3050: 3048: 3043: 3041: 3036: 3035: 3032: 3022: 3017: 3011: 2999: 2989: 2982: 2977: 2973: 2966: 2961: 2958: 2954: 2949: 2946: 2942: 2937: 2932: 2927: 2924: 2919: 2915: 2910: 2907: 2903: 2898: 2895: 2891: 2886: 2881: 2876: 2873: 2869: 2864: 2861: 2857: 2852: 2849: 2845: 2840: 2837: 2831: 2826: 2823: 2817: 2812: 2809: 2808:contradiction 2804: 2800: 2795: 2792: 2787: 2783: 2778: 2775: 2771: 2766: 2761: 2756: 2755: 2750: 2746: 2738: 2733: 2731: 2726: 2724: 2719: 2718: 2715: 2706: 2704:1-56881-262-0 2700: 2696: 2691: 2690: 2678: 2674: 2673:0-387-97710-4 2670: 2666: 2662: 2657: 2649: 2643: 2639: 2635: 2631: 2630: 2622: 2614: 2608: 2605:. MIT Press. 2604: 2603: 2595: 2581: 2577: 2571: 2557: 2553: 2547: 2539: 2533: 2529: 2522: 2518: 2509: 2506: 2504: 2501: 2498: 2495: 2493: 2490: 2488: 2485: 2483: 2480: 2478: 2475: 2474: 2468: 2466: 2465:right adjoint 2462: 2458: 2457:inverse image 2454: 2450: 2446: 2442: 2438: 2432: 2422: 2420: 2419:Vacuous truth 2416: 2412: 2408: 2404: 2400: 2384: 2376: 2372: 2353: 2347: 2339: 2334: 2319:The empty set 2316: 2314: 2310: 2306: 2302: 2298: 2282: 2270: 2264: 2239: 2227: 2215: 2209: 2191: 2185: 2175: 2170: 2159: 2158: 2157: 2155: 2151: 2147: 2143: 2139: 2118: 2112: 2102: 2097: 2081: 2075: 2068: 2067: 2066: 2064: 2063: 2058: 2056: 2045: 2044:instantiation 2041: 2038: 2036: 2035:instantiation 2032: 2029: 2028: 2027: 2026: 2023: 2020: 2019: 2016: 2013: 2012: 2006: 2001: 1999: 1994: 1992: 1987: 1985: 1984:Transposition 1982: 1980: 1977: 1975: 1970: 1968: 1963: 1961: 1959:Commutativity 1956: 1954: 1952:Associativity 1949: 1948: 1946: 1945: 1942: 1939: 1938: 1933: 1930: 1928: 1926: 1920: 1918: 1917:modus tollens 1912: 1907: 1905: 1899: 1894: 1892: 1886: 1881: 1879: 1873: 1868: 1866: 1860: 1855: 1853: 1847: 1842: 1840: 1837: 1834:elimination ( 1830: 1825: 1824: 1823: 1822: 1819: 1816: 1815: 1812: 1809: 1808: 1805: 1802: 1801: 1793: 1774: 1768: 1758: 1753: 1746: 1740: 1734: 1724: 1719: 1700: 1694: 1691: 1685: 1679: 1669: 1664: 1652: 1632: 1626: 1616: 1611: 1598: 1592: 1586: 1576: 1571: 1567: 1560: 1559: 1558: 1538: 1532: 1519: 1514: 1504: 1498: 1492: 1482: 1477: 1461: 1455: 1449: 1436: 1431: 1421: 1415: 1409: 1399: 1394: 1377: 1376: 1375: 1371: 1369: 1347: 1341: 1328: 1323: 1313: 1307: 1301: 1291: 1286: 1269: 1268: 1267: 1265: 1261: 1239: 1233: 1220: 1215: 1204: 1203: 1202: 1200: 1196: 1174: 1168: 1158: 1153: 1142: 1141: 1140: 1119: 1113: 1103: 1098: 1081: 1080: 1079: 1077: 1055: 1049: 1039: 1034: 1023: 1022: 1021: 1019: 1015: 1011: 1007: 1003: 998: 962: 948: 928: 920: 916: 915: 910: 890: 887: 884: 881: 878: 870: 854: 846: 845: 844: 830: 827: 824: 821: 818: 815: 806: 801: 789: 785: 781: 771: 769: 765: 761: 741: 738: 735: 732: 729: 709: 689: 681: 680: 679: 677: 658: 655: 652: 649: 646: 626: 618: 617: 616: 614: 610: 606: 590: 587: 584: 581: 578: 558: 551: 546: 544: 528: 525: 522: 519: 516: 496: 493: 490: 487: 484: 476: 471: 469: 465: 449: 446: 443: 440: 437: 417: 414: 411: 408: 405: 385: 382: 379: 376: 373: 349: 346: 343: 340: 337: 317: 309: 308: 307: 305: 302:Consider the 295: 293: 285: 268: 263: 261: 257: 253: 247: 239: 232: 226: 222: 219: 215: 211: 207: 204:is a type of 203: 199: 175: 169: 166: 156: 152: 136: 113: 107: 100:is true when 84: 78: 75: 65: 61: 58: 55: 51: 48: 45: 41: 33: 26: 22: 4769: 4567:Ultraproduct 4414:Model theory 4379:Independence 4315:Formal proof 4307:Proof theory 4290: 4263: 4220:real numbers 4192:second-order 4103:Substitution 4053: 3980:Metalanguage 3921:conservative 3894:Axiom schema 3838:Constructive 3808:Morse–Kelley 3774:Set theories 3753:Aleph number 3746:inaccessible 3652:Grothendieck 3536:intersection 3423:Higher-order 3411:Second-order 3357:Truth tables 3314:Venn diagram 3097:Formal proof 2985: 2980: 2935: 2884: 2764: 2694: 2676: 2664: 2656: 2628: 2621: 2602:Logic Primer 2601: 2594: 2583:. Retrieved 2579: 2570: 2559:. Retrieved 2555: 2546: 2527: 2521: 2445:left adjoint 2434: 2414: 2410: 2406: 2402: 2397:denotes the 2374: 2370: 2323:The formula 2322: 2312: 2308: 2304: 2300: 2296: 2257: 2153: 2149: 2145: 2136: 2060: 2059: 2052: 2042: / 2033: / 1924: 1921: / 1916: 1913: / 1900: / 1897:Constructive 1887: / 1874: / 1861: / 1848: / 1836:modus ponens 1835: 1831: / 1653: 1650: 1556: 1372: 1365: 1257: 1198: 1194: 1192: 1138: 1075: 1073: 1017: 1013: 1009: 1005: 1001: 999: 973: 912: 906: 777: 757: 673: 608: 547: 474: 472: 468:real numbers 365: 301: 280:THERE EXISTS 264: 259: 255: 245: 237: 230: 224: 201: 195: 4677:Type theory 4625:undecidable 4557:Truth value 4444:equivalence 4123:non-logical 3736:Enumeration 3726:Isomorphism 3673:cardinality 3657:Von Neumann 3622:Ultrafilter 3587:Uncountable 3521:equivalence 3438:Quantifiers 3428:Fixed-point 3397:First-order 3277:Consistency 3262:Proposition 3239:Traditional 3210:Lindström's 3200:Compactness 3142:Type theory 3087:Cardinality 2986:existential 1997:Exportation 1884:Disjunctive 1877:elimination 1864:elimination 1851:elimination 722:is odd and 550:even number 214:interpreted 4792:Categories 4488:elementary 4181:arithmetic 4049:Quantifier 4027:functional 3899:Expression 3617:Transitive 3561:identities 3546:complement 3479:hereditary 3462:Set theory 2686:References 2612:0262303965 2585:2020-09-04 2561:2020-09-04 2453:power sets 2425:As adjoint 1910:Absorption 965:Properties 871:such that 788:sans-serif 206:quantifier 47:Quantifier 4759:Supertask 4662:Recursion 4620:decidable 4454:saturated 4432:of models 4355:deductive 4350:axiomatic 4270:Hilbert's 4257:Euclidean 4238:canonical 4161:axiomatic 4093:Signature 4022:Predicate 3911:Extension 3833:Ackermann 3758:Operation 3637:Universal 3627:Recursive 3602:Singleton 3597:Inhabited 3582:Countable 3572:Types of 3556:power set 3526:partition 3443:Predicate 3389:Predicate 3304:Syllogism 3294:Soundness 3267:Inference 3257:Tautology 3159:paradoxes 2970:universal 2848:therefore 2836:therefore 2791:tautology 2677:See p. 58 2401:, and no 2399:empty set 2385:∅ 2344:∅ 2340:∈ 2331:∃ 2277:→ 2234:→ 2222:→ 2198:→ 2176:∈ 2167:∃ 2152:in which 2103:∈ 2094:∃ 2088:→ 2004:Tautology 1759:∈ 1750:∃ 1747:∨ 1725:∈ 1716:∃ 1707:→ 1692:∨ 1670:∈ 1661:∃ 1617:∈ 1608:∃ 1602:¬ 1599:≡ 1577:∈ 1568:∄ 1530:¬ 1520:∈ 1511:∃ 1505:≡ 1483:∈ 1474:∀ 1468:¬ 1447:¬ 1437:∈ 1428:∀ 1422:≡ 1400:∈ 1391:∃ 1385:¬ 1339:¬ 1329:∈ 1320:∀ 1314:≡ 1292:∈ 1283:∃ 1277:¬ 1231:¬ 1221:∈ 1212:∀ 1159:∈ 1150:∃ 1104:∈ 1095:∃ 1089:¬ 1040:∈ 1031:∃ 982:¬ 949:∪ 929:∩ 882:× 822:× 807:∈ 798:∃ 733:× 650:× 582:× 520:× 488:× 441:× 409:× 377:× 341:× 306:sentence 286:, and as 212:which is 164:∃ 73:∃ 63:Statement 25:Yo (kana) 4744:Logicism 4737:timeline 4713:Concrete 4572:Validity 4542:T-schema 4535:Kripke's 4530:Tarski's 4525:semantic 4515:Strength 4464:submodel 4459:spectrum 4427:function 4275:Tarski's 4264:Elements 4251:geometry 4207:Robinson 4128:variable 4113:function 4086:spectrum 4076:Sentence 4032:variable 3975:Language 3928:Relation 3889:Automata 3879:Alphabet 3863:language 3717:-jection 3695:codomain 3681:Function 3642:Universe 3612:Infinite 3516:Relation 3299:Validity 3289:Argument 3187:theorem, 2923:superset 2834:entails, 2820:entails, 2471:See also 2451:between 1462:≢ 970:Negation 774:Notation 543:solution 277:∃ 4686:Related 4483:Diagram 4381: ( 4360:Hilbert 4345:Systems 4340:Theorem 4218:of the 4163:systems 3943:Formula 3938:Grammar 3854: ( 3798:General 3511:Forcing 3496:Element 3416:Monadic 3191:paradox 3132:Theorem 3068:General 2939:  2918:implies 2906:implies 2888:  2860:because 2768:  2743:Common 2463:is the 2449:functor 786:" in a 288:\exists 284:Unicode 4449:finite 4212:Skolem 4165:  4140:Theory 4108:Symbol 4098:String 4081:atomic 3958:ground 3953:closed 3948:atomic 3904:ground 3867:syntax 3763:binary 3690:domain 3607:Finite 3372:finite 3230:Logics 3189:  3137:Theory 2933:  2882:  2822:proves 2762:  2701:  2671:  2644:  2609:  2534:  2455:, the 2280:  2237:  2225:  2201:  2091:  1710:  1605:  1508:  1471:  1465:  1425:  1388:  1317:  1280:  1092:  985:  304:formal 298:Basics 274: 272:U+2203 242:" or " 234:" or " 221:symbol 4439:Model 4187:Peano 4044:Proof 3884:Arity 3813:Naive 3700:image 3632:Fuzzy 3592:Empty 3541:union 3486:Class 3127:Model 3117:Lemma 3075:Axiom 2803:false 2770:& 2514:Notes 2447:of a 430:, or 398:, or 292:LaTeX 200:, an 53:Field 4562:Type 4365:list 4169:list 4146:list 4135:Term 4069:rank 3963:open 3857:list 3669:Maps 3574:sets 3433:Free 3403:list 3153:list 3080:list 2957:nand 2786:true 2699:ISBN 2669:ISBN 2642:ISBN 2607:ISBN 2532:ISBN 941:and 758:The 208:, a 43:Type 4249:of 4231:of 4179:of 3711:Sur 3685:Map 3492:Ur- 3474:Set 2945:iff 2894:not 2774:and 2634:doi 2435:In 911:in 778:In 674:is 470:.) 290:in 282:in 256:all 196:In 4794:: 4635:NP 4259:: 4253:: 4183:: 3860:), 3715:Bi 3707:In 2936:or 2885:or 2872:or 2765:or 2675:. 2640:. 2578:. 2554:. 2467:. 2053:A 1197:, 891:25 831:25 742:25 702:, 659:25 639:, 591:25 571:, 529:25 497:25 450:25 418:25 386:25 350:25 330:, 248:)" 244:(∃ 236:∃( 227:(" 4715:/ 4630:P 4385:) 4171:) 4167:( 4064:∀ 4059:! 4054:∃ 4015:= 4010:↔ 4005:→ 4000:∧ 3995:∨ 3990:¬ 3713:/ 3709:/ 3683:/ 3494:) 3490:( 3377:∞ 3367:3 3155:) 3053:e 3046:t 3039:v 2981:∃ 2965:∀ 2953:| 2941:≡ 2931:↔ 2920:, 2914:⊃ 2902:→ 2890:~ 2880:¬ 2868:∨ 2856:∵ 2844:∴ 2830:⊨ 2816:⊢ 2805:, 2799:⊥ 2788:, 2782:⊤ 2760:∧ 2736:e 2729:t 2722:v 2707:. 2679:. 2650:. 2636:: 2615:. 2588:. 2564:. 2540:. 2415:x 2413:( 2411:P 2407:x 2403:x 2375:x 2373:( 2371:P 2357:) 2354:x 2351:( 2348:P 2335:x 2313:c 2311:( 2309:P 2305:c 2301:X 2297:c 2283:Q 2274:) 2271:c 2268:( 2265:P 2243:) 2240:Q 2231:) 2228:Q 2219:) 2216:c 2213:( 2210:P 2207:( 2204:( 2195:) 2192:x 2189:( 2186:P 2181:X 2171:x 2154:c 2150:Q 2146:c 2122:) 2119:x 2116:( 2113:P 2108:X 2098:x 2085:) 2082:a 2079:( 2076:P 1838:) 1781:) 1778:) 1775:x 1772:( 1769:Q 1764:X 1754:x 1744:) 1741:x 1738:( 1735:P 1730:X 1720:x 1713:( 1704:) 1701:x 1698:( 1695:Q 1689:) 1686:x 1683:( 1680:P 1675:X 1665:x 1636:) 1633:x 1630:( 1627:P 1622:X 1612:x 1596:) 1593:x 1590:( 1587:P 1582:X 1572:x 1542:) 1539:x 1536:( 1533:P 1525:X 1515:x 1502:) 1499:x 1496:( 1493:P 1488:X 1478:x 1459:) 1456:x 1453:( 1450:P 1442:X 1432:x 1419:) 1416:x 1413:( 1410:P 1405:X 1395:x 1351:) 1348:x 1345:( 1342:P 1334:X 1324:x 1311:) 1308:x 1305:( 1302:P 1297:X 1287:x 1243:) 1240:x 1237:( 1234:P 1226:X 1216:x 1199:x 1195:x 1178:) 1175:x 1172:( 1169:P 1164:X 1154:x 1135:. 1123:) 1120:x 1117:( 1114:P 1109:X 1099:x 1076:x 1059:) 1056:x 1053:( 1050:P 1045:X 1035:x 1018:x 1014:X 1010:x 1006:x 1004:( 1002:P 903:. 888:= 885:n 879:n 855:n 828:= 825:n 819:n 816:: 812:N 802:n 784:E 754:. 739:= 736:n 730:n 710:n 690:n 656:= 653:n 647:n 627:n 609:n 588:= 585:n 579:n 559:n 526:= 523:n 517:n 494:= 491:5 485:5 475:n 447:= 444:2 438:2 415:= 412:1 406:1 383:= 380:0 374:0 362:. 347:= 344:n 338:n 318:n 246:x 240:) 238:x 231:x 229:∃ 179:) 176:x 173:( 170:P 167:x 149:. 137:x 117:) 114:x 111:( 108:P 88:) 85:x 82:( 79:P 76:x 34:. 27:. 21:Ǝ

Index

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
natural numbers

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