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Material conditional

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6894: 5137: 4426: 2743: 1491: 50: 4319: 130: 5126: 4820: 3622:, the natural language statement "If 8 is odd, then 3 is prime" is typically judged false. Similarly, any material conditional with a true consequent is itself true, but speakers typically reject sentences such as "If I have a penny in my pocket, then Paris is in France". These classic problems have been called the 3704:
study, where less than 10% of participants reasoned according to the material conditional. Some researchers have interpreted this result as a failure of the participants to conform to normative laws of reasoning, while others interpret the participants as reasoning normatively according to
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has generally eschewed material implication as an analysis for natural-language conditionals. In particular, such work has often rejected the assumption that natural-language conditionals are
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Stenning, K.; van Lambalgen, M. (2004). "A little logic goes a long way: basing experiment on semantic theory in the cognitive science of conditional reasoning".
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of the conditional. Conditional statements may be nested such that the antecedent or the consequent may themselves be conditional statements, as in the formula
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Unlike the semantic definition, this approach to logical connectives permits the examination of structurally identical propositional forms in various
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principles could explain the discrepancies between natural language conditionals and the material conditional. On their accounts, conditionals
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operator which returns "true" unless its first argument is true and its second argument is false. This semantics can be shown graphically in a
4370: 1931: 6031: 5172: 2341: 3364: 3626:. In addition to the paradoxes, a variety of other arguments have been given against a material implication analysis. For instance, 3938:"elementary set theory – Is there any connection between the symbol ⊃ when it means implication and its meaning as superset?" 3757: 330: 31: 3370: 6345: 3912: 20: 6503: 4323: 4101: 3870: 5291: 1671:. It is assumed as a model of correct conditional reasoning within mathematics and serves as the basis for commands in many 6358: 5681: 4848: 4028: 3735: 1504: 3303: 4340: 3700:
Similar discrepancies have been observed by psychologists studying conditional reasoning, for instance, by the notorious
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material implication but end up conveying additional information when they interact with conversational norms such as
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Similarly, on classical interpretations of the other connectives, material implication validates the following
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Oaksford, M.; Chater, N. (1994). "A rational analysis of the selection task as optimal data selection".
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In logic and related fields, the material conditional is customarily notated with an infix operator
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and related problems, material implication is not generally considered a viable analysis of
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Towards a Flexible Bayesian and Deontic Logic of Testing Descriptive and Prescriptive Rules
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with the symbol Ɔ, which is the opposite of C. He also expressed the proposition
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Note that the horseshoe symbol Ɔ has been flipped to become a subset symbol ⊂.
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are classical, material implication validates the following equivalences:
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is false. Material implication can also be characterized inferentially by
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From Frege to Gödel: A Source Book in Mathematical Logic, 1879–1931
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Prinzipien der Mathematik (Lecture Notes edited by Bernays, P.)
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such as the one below. One can also consider the equivalence
1723:. The material conditional is also notated using the infixes 129: 3434:{\displaystyle (P\lor Q)\to R\models (P\to R)\land (Q\to R)} 3633:
In the mid-20th century, a number of researchers including
4207:(doctoralThesis). Göttingen: Göttingen University Press. 3610:
Material implication does not closely match the usage of
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Material implication is used in all the basic systems of
2133:(1910–1913), in which he expressed the proposition "If 3605: 4795: 4758: 4729: 4704: 4675: 4628: 4599: 4570: 4533: 4504: 4475: 4450: 4404: 4163: 3552: 3494: 3460: 3373: 3306: 3266: 3211: 3098: 3003: 2960: 2908: 2844: 2795: 2685: 2494: 2473: 2452: 2421: 2344: 2287: 2249: 2223: 2185: 2147: 2103: 2071: 2051: 2025: 2005: 1985: 1965: 1945: 1877: 1851: 1825: 1799: 1773: 1749: 1729: 1709: 1623: 1603: 1577: 1553: 1375: 1349: 1323: 1289: 1256: 1214: 1180: 1154: 1128: 1102: 1071: 1044: 1021: 998: 955: 929: 896: 862: 836: 810: 769: 743: 717: 684: 650: 624: 598: 564: 538: 512: 475: 449: 426: 400: 374: 234: 193: 152: 99: 65: 3355:{\displaystyle (P\to Q)\land (Q\to R)\models P\to R} 3885: 2893:{\displaystyle P\to (Q\to R)\equiv (P\land Q)\to R} 2728:
the material conditional is used to define negation
2601:, then Galileo Galilei is a brother of Marie Curie" 4801: 4764: 4735: 4710: 4681: 4634: 4605: 4576: 4539: 4510: 4481: 4456: 4410: 4241:Boolean Reasoning: The Logic of Boolean Equations 3979: 3977: 3975: 3973: 3595:{\displaystyle \models (P\to Q)\lor (P\to \neg Q)} 3594: 3533: 3475: 3433: 3354: 3287: 3247: 3186: 3079: 2987: 2944: 2892: 2825: 2718: 2506: 2479: 2458: 2433: 2395: 2299: 2261: 2235: 2197: 2159: 2115: 2077: 2057: 2037: 2011: 1991: 1971: 1951: 1913: 1857: 1831: 1811: 1785: 1755: 1735: 1715: 1629: 1609: 1589: 1559: 1387: 1361: 1335: 1301: 1275: 1234: 1192: 1166: 1140: 1114: 1080: 1057: 1030: 1007: 976: 941: 915: 874: 848: 822: 790: 755: 729: 703: 662: 636: 610: 576: 550: 524: 490: 461: 435: 412: 386: 255: 212: 171: 111: 77: 3966:. Paris: Hermann & Cie, Éditeurs. p. 14. 2945:{\displaystyle \neg (P\to Q)\equiv P\land \neg Q} 6910: 3935: 3630:would all be vacuously true on such an account. 2719:{\displaystyle (A\to B)\Rightarrow \neg A\lor B} 4076:Semantics: An international handbook of meaning 3970: 2633:Material implication can also be characterized 4378: 4116: 4034:. In Hale, B.; Wright, C.; Miller, A. (eds.). 3673:" is determined solely by the truth values of 5166: 4849: 4364: 3910: 3838: 3836: 3534:{\displaystyle \models (P\to Q)\lor (Q\to P)} 3248:{\displaystyle P\to Q\models (P\land R)\to Q} 3179: 3139: 3129: 3101: 3072: 3044: 3034: 3006: 2826:{\displaystyle P\to Q\equiv \neg Q\to \neg P} 1932:Arithmetices Principia: Nova Methodo Exposita 1512: 331: 4265:(2001), "Conditionals", in Lou Goble (ed.), 4194: 3955: 3890:. Harvard University Press. pp. 84–87. 5358: 5173: 5159: 4863: 4856: 4842: 4371: 4357: 4267:The Blackwell Guide to Philosophical Logic 4066: 4022: 4020: 4018: 3833: 1519: 1505: 338: 324: 4212: 4200: 4177: 4132: 4091: 4078:. de Gruyter Mouton. pp. 1515–1538. 4036:A Companion to the Philosophy of Language 3983: 3857: 3665:in the sense that the truth value of "If 3365:Simplification of disjunctive antecedents 2988:{\displaystyle P\to Q\equiv \neg P\lor Q} 2243:at first but later came to express it as 3961: 3758:Material implication (rule of inference) 3447:involving material implication include: 32:Material implication (rule of inference) 4026: 4015: 4009:The Stanford Encyclopedia of Philosophy 3990:The Stanford Encyclopedia of Philosophy 3842: 2628: 2563:The logical cases where the antecedent 849:{\displaystyle A\not \Leftrightarrow B} 6911: 5180: 1276:{\displaystyle A{\underline {\lor }}B} 791:{\displaystyle {\overline {A\cdot B}}} 704:{\displaystyle A{\overline {\land }}B} 5154: 4837: 4606:{\displaystyle \not \leftrightarrow } 4352: 4329: 4038:. Wiley Blackwell. pp. 401–436. 4002: 916:{\displaystyle A{\overline {\lor }}B} 577:{\displaystyle A\leftrightharpoons B} 3736:Implicational propositional calculus 3288:{\displaystyle \neg P\models P\to Q} 2737: 2733: 2726:is not a propositional theorem, but 1914:{\displaystyle (p\to q)\to (r\to s)} 4341:Stanford Encyclopedia of Philosophy 3606:Discrepancies with natural language 1571:as material implication, a formula 1235:{\displaystyle A\ {\text{XNOR}}\ B} 875:{\displaystyle A\nleftrightarrow B} 13: 4796: 4571: 4405: 4233: 3863:Introduction to Mathematical Logic 3583: 3267: 2973: 2936: 2909: 2817: 2808: 2704: 2622:, then Marie Curie has a sibling." 2381: 2369: 2357: 999: 551:{\displaystyle A\Leftrightarrow B} 482: 479: 453: 256:{\displaystyle 1\oplus x\oplus xy} 14: 6945: 4311: 3886:Jean van Heijenoort, ed. (1967). 3624:paradoxes of material implication 1685:paradoxes of material implication 977:{\displaystyle {\overline {A+B}}} 213:{\displaystyle {\overline {x}}+y} 172:{\displaystyle {\overline {x}}+y} 6892: 5135: 5124: 4818: 4635:{\displaystyle \leftrightarrow } 4424: 4317: 2741: 1490: 1489: 128: 48: 4157: 4110: 4060: 3936:Mauro ALLEGRANZA (2015-02-13). 3779: 1058:{\displaystyle {\overline {A}}} 4676: 4629: 4505: 4476: 4451: 3996: 3929: 3904: 3879: 3851: 3813: 3589: 3580: 3574: 3568: 3562: 3556: 3528: 3522: 3516: 3510: 3504: 3498: 3476:{\displaystyle \models P\to P} 3467: 3428: 3422: 3416: 3410: 3404: 3398: 3389: 3386: 3374: 3346: 3337: 3331: 3325: 3319: 3313: 3307: 3279: 3239: 3236: 3224: 3215: 3174: 3168: 3162: 3159: 3156: 3150: 3144: 3124: 3118: 3112: 3109: 3067: 3061: 3055: 3052: 3029: 3023: 3017: 3014: 2997:Commutativity of antecedents: 2964: 2924: 2918: 2912: 2884: 2881: 2869: 2863: 2857: 2851: 2848: 2814: 2799: 2701: 2698: 2692: 2686: 2507:{\displaystyle A\rightarrow B} 2498: 2434:{\displaystyle A\rightarrow B} 2425: 2406: 2375: 2360: 2348: 2327:, material implication is the 2310: 2300:{\displaystyle A\Rightarrow B} 2291: 2273:expressed the proposition "If 2253: 2209:expressed the proposition "If 2171:expressed the proposition "If 2107: 2089:expressed the proposition "If 1939:expressed the proposition "If 1908: 1902: 1896: 1893: 1890: 1884: 1878: 1803: 1767:, conditionals are notated as 1750: 1710: 1590:{\displaystyle P\rightarrow Q} 1581: 1554: 1547:. When the conditional symbol 1379: 1327: 933: 823:{\displaystyle A\not \equiv B} 721: 663:{\displaystyle A\rightarrow B} 654: 611:{\displaystyle A\Rightarrow B} 602: 568: 542: 491:{\displaystyle A\&\&B} 106: 100: 78:{\displaystyle x\rightarrow y} 69: 1: 6853:History of mathematical logic 4711:{\displaystyle \nrightarrow } 4297:, "Indicative Conditionals", 4239:Brown, Frank Markham (2003), 4007:. In Zalta, Edward N. (ed.). 3911:Michael Nahas (25 Apr 2022). 3826: 2269:with a right-pointing arrow. 1388:{\displaystyle A\leftarrow B} 1336:{\displaystyle A\Leftarrow B} 942:{\displaystyle A\downarrow B} 6778:Primitive recursive function 4736:{\displaystyle \nleftarrow } 4511:{\displaystyle \rightarrow } 4188:10.1016/j.cogsci.2004.02.002 3988:. In Edward N. Zalta (ed.). 3944:. Stack Exchange Inc. Answer 2315: 1756:{\displaystyle \Rightarrow } 1560:{\displaystyle \rightarrow } 1193:{\displaystyle A\parallel B} 1050: 969: 905: 783: 693: 199: 158: 7: 4682:{\displaystyle \downarrow } 4482:{\displaystyle \leftarrow } 4143:10.1037/0033-295X.101.4.608 3984:Edgington, Dorothy (2008). 3708: 3628:counterfactual conditionals 3544:Conditional excluded middle 1793:. In a conditional formula 1698: 1681:variably strict conditional 730:{\displaystyle A\uparrow B} 10: 6950: 5842:Schröder–Bernstein theorem 5569:Monadic predicate calculus 5228:Foundations of mathematics 4084:10.1515/9783110255072.1515 4044:10.1002/9781118972090.ch17 3942:Mathematics Stack Exchange 3791:Counterfactual conditional 3205:Antecedent strengthening: 2637:in terms of the following 2236:{\displaystyle A\supset B} 2198:{\displaystyle A\supset B} 2160:{\displaystyle A\supset B} 2038:{\displaystyle A\supset B} 1924: 1362:{\displaystyle A\subset B} 637:{\displaystyle A\supset B} 25: 18: 6888: 6875:Philosophy of mathematics 6824:Automated theorem proving 6806: 6701: 6533: 6426: 6278: 5995: 5971: 5949:Von Neumann–Bernays–Gödel 5894: 5788: 5692: 5590: 5581: 5508: 5443: 5349: 5271: 5188: 5121: 4872: 4815: 4778: 4658: 4553: 4457:{\displaystyle \uparrow } 4433: 4422: 4387: 3786:Corresponding conditional 1302:{\displaystyle A\oplus B} 525:{\displaystyle A\equiv B} 319: 311: 301: 291: 283: 275: 266: 223: 182: 141: 136: 122: 88: 56: 47: 42: 4285:Harvard University Press 4067:von Fintel, Kai (2011). 3806: 3773:Sole sufficient operator 2658:Classical contraposition 1736:{\displaystyle \supset } 462:{\displaystyle A\&B} 413:{\displaystyle A\cdot B} 387:{\displaystyle A\land B} 26:Not to be confused with 6525:Self-verifying theories 6346:Tarski's axiomatization 5297:Tarski's undefinability 5292:incompleteness theorems 4721:Converse nonimplication 4027:Gillies, Thony (2017). 3992:(Winter 2008 ed.). 1442:Functional completeness 1167:{\displaystyle A\mid B} 1115:{\displaystyle A\lor B} 756:{\displaystyle A\mid B} 6899:Mathematics portal 6510:Proof of impossibility 6158:propositional variable 5468:Propositional calculus 5142:Mathematics portal 4803: 4766: 4765:{\displaystyle \land } 4737: 4712: 4683: 4636: 4607: 4578: 4541: 4512: 4483: 4458: 4412: 4201:von Sydow, M. (2006). 3796:Indicative conditional 3768:Propositional calculus 3731:Conditional quantifier 3659:philosophy of language 3596: 3535: 3477: 3435: 3356: 3289: 3249: 3188: 3081: 2989: 2946: 2902:Negated conditionals: 2894: 2827: 2720: 2508: 2481: 2460: 2435: 2397: 2301: 2263: 2262:{\displaystyle A\to B} 2237: 2199: 2161: 2127:followed Peano in his 2117: 2116:{\displaystyle A\to B} 2079: 2059: 2039: 2013: 1993: 1973: 1953: 1915: 1859: 1839:is referred to as the 1833: 1813: 1812:{\displaystyle p\to q} 1787: 1757: 1737: 1717: 1631: 1611: 1591: 1561: 1412:Propositional calculus 1389: 1363: 1337: 1303: 1277: 1236: 1194: 1168: 1142: 1116: 1082: 1081:{\displaystyle \sim A} 1059: 1032: 1009: 1008:{\displaystyle \neg A} 978: 943: 917: 876: 850: 824: 792: 757: 731: 705: 664: 638: 612: 578: 552: 526: 492: 463: 437: 414: 388: 257: 214: 173: 113: 112:{\displaystyle (1011)} 79: 6768:Kolmogorov complexity 6721:Computably enumerable 6621:Model complete theory 6413:Principia Mathematica 5473:Propositional formula 5302:Banach–Tarski paradox 5131:Philosophy portal 4825:Philosophy portal 4804: 4802:{\displaystyle \bot } 4767: 4738: 4713: 4684: 4637: 4608: 4579: 4577:{\displaystyle \neg } 4542: 4540:{\displaystyle \lor } 4513: 4484: 4459: 4413: 4411:{\displaystyle \top } 4247:Academic Publishers, 3964:Théorie des ensembles 3962:Bourbaki, N. (1954). 3612:conditional sentences 3597: 3536: 3478: 3436: 3357: 3290: 3250: 3189: 3082: 2990: 2947: 2895: 2828: 2721: 2577:is true, are called " 2509: 2482: 2461: 2436: 2398: 2302: 2264: 2238: 2200: 2167:. Following Russell, 2162: 2130:Principia Mathematica 2118: 2080: 2060: 2040: 2014: 1994: 1974: 1954: 1916: 1860: 1834: 1814: 1788: 1758: 1738: 1718: 1689:conditional sentences 1673:programming languages 1632: 1612: 1592: 1562: 1470:Programming languages 1390: 1364: 1338: 1304: 1278: 1237: 1195: 1169: 1143: 1117: 1083: 1060: 1033: 1010: 979: 944: 918: 877: 851: 825: 793: 758: 732: 706: 665: 639: 613: 579: 553: 527: 493: 464: 438: 415: 389: 258: 215: 174: 114: 80: 21:Conditional statement 6716:Church–Turing thesis 6703:Computability theory 5912:continuum hypothesis 5430:Square of opposition 5288:Gödel's completeness 4793: 4756: 4727: 4702: 4673: 4626: 4597: 4568: 4531: 4502: 4473: 4467:Converse implication 4448: 4402: 4330:Edgington, Dorothy. 4326:at Wikimedia Commons 4324:Material conditional 4251:, MA. 2nd edition, 4214:10.53846/goediss-161 4120:Psychological Review 4003:Starr, Will (2019). 3918:. GitHub. p. VI 3843:Hilbert, D. (1918). 3702:Wason selection task 3550: 3492: 3458: 3371: 3304: 3264: 3209: 3096: 3001: 2958: 2906: 2842: 2793: 2683: 2677:intuitionistic logic 2665:reductio ad absurdum 2629:Deductive definition 2581:". Examples are ... 2492: 2471: 2450: 2419: 2342: 2325:semantic perspective 2285: 2247: 2221: 2183: 2145: 2101: 2069: 2049: 2023: 2003: 1983: 1963: 1943: 1875: 1849: 1823: 1797: 1771: 1747: 1727: 1716:{\displaystyle \to } 1707: 1657:reductio ad absurdum 1621: 1601: 1575: 1551: 1537:material implication 1533:material conditional 1373: 1347: 1321: 1287: 1254: 1212: 1178: 1152: 1126: 1100: 1069: 1042: 1019: 996: 953: 927: 894: 860: 834: 808: 767: 741: 715: 682: 648: 622: 596: 562: 536: 510: 473: 447: 424: 398: 372: 232: 225:Zhegalkin polynomial 191: 150: 97: 63: 38:Material conditional 6929:Logical consequence 6919:Logical connectives 6870:Mathematical object 6761:P versus NP problem 6726:Computable function 6520:Reverse mathematics 6446:Logical consequence 6323:primitive recursive 6318:elementary function 6091:Free/bound variable 5944:Tarski–Grothendieck 5463:Logical connectives 5393:Logical equivalence 5243:Logical consequence 4381:logical connectives 3753:Logical equivalence 3705:nonclassical laws. 3258:Vacuous conditional 3090:Left distributivity 1786:{\displaystyle Cpq} 1669:nonclassical logics 1480:Philosophy of logic 1141:{\displaystyle A+B} 354:Logical connectives 39: 6668:Transfer principle 6631:Semantics of logic 6616:Categorical theory 6592:Non-standard model 6106:Logical connective 5233:Information theory 5182:Mathematical logic 4799: 4762: 4733: 4708: 4679: 4632: 4603: 4574: 4537: 4508: 4479: 4454: 4438:Alternative denial 4408: 4263:Edgington, Dorothy 4253:Dover Publications 3859:Mendelson, Elliott 3801:Strict conditional 3691:probability theory 3592: 3531: 3473: 3431: 3352: 3285: 3245: 3184: 3077: 2985: 2942: 2890: 2823: 2753:. You can help by 2716: 2639:rules of inference 2504: 2477: 2456: 2431: 2393: 2297: 2259: 2233: 2195: 2157: 2113: 2075: 2055: 2035: 2009: 1989: 1969: 1949: 1911: 1855: 1829: 1809: 1783: 1763:. In the prefixed 1753: 1733: 1713: 1677:strict conditional 1627: 1607: 1587: 1557: 1475:Mathematical logic 1385: 1359: 1333: 1299: 1273: 1268: 1232: 1190: 1164: 1138: 1112: 1078: 1055: 1031:{\displaystyle -A} 1028: 1005: 974: 939: 913: 872: 846: 820: 788: 753: 727: 701: 660: 634: 608: 574: 548: 522: 488: 459: 436:{\displaystyle AB} 433: 410: 384: 253: 210: 169: 109: 75: 37: 28:Material inference 16:Logical connective 6906: 6905: 6838:Abstract category 6641:Theories of truth 6451:Rule of inference 6441:Natural deduction 6422: 6421: 5967: 5966: 5672:Cartesian product 5577: 5576: 5483:Many-valued logic 5458:Boolean functions 5341:Russell's paradox 5316:diagonal argument 5213:First-order logic 5148: 5147: 5116: 5115: 4831: 4830: 4322:Media related to 4295:Stalnaker, Robert 4166:Cognitive Science 4103:978-3-11-018523-2 4005:"Counterfactuals" 3872:978-1-4822-3778-8 3653:. Recent work in 2771: 2770: 2734:Formal properties 2653:Conditional proof 2561: 2560: 2480:{\displaystyle B} 2459:{\displaystyle A} 2078:{\displaystyle B} 2058:{\displaystyle A} 2012:{\displaystyle B} 1992:{\displaystyle A} 1972:{\displaystyle B} 1952:{\displaystyle A} 1858:{\displaystyle q} 1832:{\displaystyle p} 1819:, the subformula 1651:conditional proof 1630:{\displaystyle Q} 1610:{\displaystyle P} 1543:commonly used in 1529: 1528: 1398: 1397: 1261: 1228: 1224: 1220: 1053: 972: 908: 786: 696: 348: 347: 202: 161: 6941: 6897: 6896: 6848:History of logic 6843:Category of sets 6736:Decision problem 6515:Ordinal analysis 6456:Sequent calculus 6354:Boolean algebras 6294: 6293: 6268: 6239:logical/constant 5993: 5992: 5979: 5902:Zermelo–Fraenkel 5653:Set operations: 5588: 5587: 5525: 5356: 5355: 5336:Löwenheim–Skolem 5223:Formal semantics 5175: 5168: 5161: 5152: 5151: 5140: 5139: 5129: 5128: 5127: 4973: 4922: 4888: 4875: 4874: 4858: 4851: 4844: 4835: 4834: 4823: 4822: 4821: 4808: 4806: 4805: 4800: 4771: 4769: 4768: 4763: 4742: 4740: 4739: 4734: 4717: 4715: 4714: 4709: 4688: 4686: 4685: 4680: 4641: 4639: 4638: 4633: 4612: 4610: 4609: 4604: 4583: 4581: 4580: 4575: 4546: 4544: 4543: 4538: 4517: 4515: 4514: 4509: 4488: 4486: 4485: 4480: 4463: 4461: 4460: 4455: 4428: 4417: 4415: 4414: 4409: 4373: 4366: 4359: 4350: 4349: 4345: 4336:Zalta, Edward N. 4321: 4307:(1975): 269–286. 4281:Methods of Logic 4227: 4226: 4216: 4198: 4192: 4191: 4181: 4161: 4155: 4154: 4136: 4114: 4108: 4107: 4095: 4073: 4064: 4058: 4057: 4033: 4024: 4013: 4012: 4000: 3994: 3993: 3981: 3968: 3967: 3959: 3953: 3952: 3950: 3949: 3933: 3927: 3926: 3924: 3923: 3917: 3908: 3902: 3901: 3883: 3877: 3876: 3855: 3849: 3848: 3840: 3820: 3817: 3721:Boolean function 3663:truth functional 3655:formal semantics 3635:H. P. Grice 3616:natural language 3601: 3599: 3598: 3593: 3540: 3538: 3537: 3532: 3482: 3480: 3479: 3474: 3440: 3438: 3437: 3432: 3361: 3359: 3358: 3353: 3294: 3292: 3291: 3286: 3254: 3252: 3251: 3246: 3193: 3191: 3190: 3185: 3183: 3182: 3143: 3142: 3133: 3132: 3105: 3104: 3086: 3084: 3083: 3078: 3076: 3075: 3048: 3047: 3038: 3037: 3010: 3009: 2994: 2992: 2991: 2986: 2951: 2949: 2948: 2943: 2899: 2897: 2896: 2891: 2832: 2830: 2829: 2824: 2789:Contraposition: 2766: 2763: 2745: 2738: 2725: 2723: 2722: 2717: 2611: 2590: 2576: 2566: 2513: 2511: 2510: 2505: 2486: 2484: 2483: 2478: 2465: 2463: 2462: 2457: 2444: 2443: 2440: 2438: 2437: 2432: 2402: 2400: 2399: 2394: 2332:truth functional 2306: 2304: 2303: 2298: 2268: 2266: 2265: 2260: 2242: 2240: 2239: 2234: 2204: 2202: 2201: 2196: 2166: 2164: 2163: 2158: 2122: 2120: 2119: 2114: 2084: 2082: 2081: 2076: 2064: 2062: 2061: 2056: 2044: 2042: 2041: 2036: 2018: 2016: 2015: 2010: 1998: 1996: 1995: 1990: 1978: 1976: 1975: 1970: 1958: 1956: 1955: 1950: 1920: 1918: 1917: 1912: 1864: 1862: 1861: 1856: 1838: 1836: 1835: 1830: 1818: 1816: 1815: 1810: 1792: 1790: 1789: 1784: 1762: 1760: 1759: 1754: 1742: 1740: 1739: 1734: 1722: 1720: 1719: 1714: 1693:natural language 1667:as well as some 1636: 1634: 1633: 1628: 1616: 1614: 1613: 1608: 1596: 1594: 1593: 1588: 1566: 1564: 1563: 1558: 1521: 1514: 1507: 1493: 1492: 1437:Boolean function 1403:Related concepts 1394: 1392: 1391: 1386: 1368: 1366: 1365: 1360: 1342: 1340: 1339: 1334: 1308: 1306: 1305: 1300: 1282: 1280: 1279: 1274: 1269: 1241: 1239: 1238: 1233: 1226: 1225: 1222: 1218: 1199: 1197: 1196: 1191: 1173: 1171: 1170: 1165: 1147: 1145: 1144: 1139: 1121: 1119: 1118: 1113: 1087: 1085: 1084: 1079: 1064: 1062: 1061: 1056: 1054: 1046: 1037: 1035: 1034: 1029: 1014: 1012: 1011: 1006: 983: 981: 980: 975: 973: 968: 957: 948: 946: 945: 940: 922: 920: 919: 914: 909: 901: 881: 879: 878: 873: 855: 853: 852: 847: 829: 827: 826: 821: 797: 795: 794: 789: 787: 782: 771: 762: 760: 759: 754: 736: 734: 733: 728: 710: 708: 707: 702: 697: 689: 669: 667: 666: 661: 643: 641: 640: 635: 617: 615: 614: 609: 583: 581: 580: 575: 557: 555: 554: 549: 531: 529: 528: 523: 497: 495: 494: 489: 468: 466: 465: 460: 442: 440: 439: 434: 419: 417: 416: 411: 393: 391: 390: 385: 361: 360: 350: 349: 340: 333: 326: 270: 262: 260: 259: 254: 219: 217: 216: 211: 203: 195: 178: 176: 175: 170: 162: 154: 132: 118: 116: 115: 110: 84: 82: 81: 76: 52: 40: 36: 6949: 6948: 6944: 6943: 6942: 6940: 6939: 6938: 6909: 6908: 6907: 6902: 6891: 6884: 6829:Category theory 6819:Algebraic logic 6802: 6773:Lambda calculus 6711:Church encoding 6697: 6673:Truth predicate 6529: 6495:Complete theory 6418: 6287: 6283: 6279: 6274: 6266: 5986: and  5982: 5977: 5963: 5939:New Foundations 5907:axiom of choice 5890: 5852:Gödel numbering 5792: and  5784: 5688: 5573: 5523: 5504: 5453:Boolean algebra 5439: 5403:Equiconsistency 5368:Classical logic 5345: 5326:Halting problem 5314: and  5290: and  5278: and  5277: 5272:Theorems ( 5267: 5184: 5179: 5149: 5144: 5134: 5133: 5125: 5123: 5117: 5112: 5108: 5100: 5096: 5088: 5085: 5082: 5074: 5071: 5068: 5060: 5056: 5051: 5043: 5039: 5034: 5026: 5025: 5022: 5018: 5010: 5009: 5006: 5002: 4994: 4990: 4982: 4978: 4969: 4960: 4956: 4951: 4943: 4939: 4931: 4927: 4918: 4909: 4905: 4897: 4893: 4884: 4868: 4866:logical symbols 4862: 4832: 4827: 4819: 4817: 4811: 4794: 4791: 4790: 4774: 4757: 4754: 4753: 4728: 4725: 4724: 4703: 4700: 4699: 4674: 4671: 4670: 4654: 4627: 4624: 4623: 4598: 4595: 4594: 4569: 4566: 4565: 4549: 4532: 4529: 4528: 4503: 4500: 4499: 4474: 4471: 4470: 4449: 4446: 4445: 4429: 4420: 4403: 4400: 4399: 4383: 4377: 4314: 4243:, 1st edition, 4236: 4234:Further reading 4231: 4230: 4199: 4195: 4162: 4158: 4134:10.1.1.174.4085 4115: 4111: 4104: 4071: 4065: 4061: 4054: 4031: 4025: 4016: 4001: 3997: 3982: 3971: 3960: 3956: 3947: 3945: 3934: 3930: 3921: 3919: 3915: 3909: 3905: 3898: 3884: 3880: 3873: 3856: 3852: 3841: 3834: 3829: 3824: 3823: 3818: 3814: 3809: 3782: 3777: 3711: 3687:relevance logic 3608: 3551: 3548: 3547: 3493: 3490: 3489: 3459: 3456: 3455: 3372: 3369: 3368: 3305: 3302: 3301: 3265: 3262: 3261: 3210: 3207: 3206: 3178: 3177: 3138: 3137: 3128: 3127: 3100: 3099: 3097: 3094: 3093: 3071: 3070: 3043: 3042: 3033: 3032: 3005: 3004: 3002: 2999: 2998: 2959: 2956: 2955: 2907: 2904: 2903: 2843: 2840: 2839: 2794: 2791: 2790: 2767: 2761: 2758: 2751:needs expansion 2736: 2684: 2681: 2680: 2673:logical systems 2631: 2620:Galileo Galilei 2618:is a sister of 2607: 2599:Galileo Galilei 2597:is a sister of 2586: 2568: 2564: 2493: 2490: 2489: 2472: 2469: 2468: 2451: 2448: 2447: 2420: 2417: 2416: 2409: 2343: 2340: 2339: 2318: 2313: 2286: 2283: 2282: 2248: 2245: 2244: 2222: 2219: 2218: 2184: 2181: 2180: 2146: 2143: 2142: 2102: 2099: 2098: 2070: 2067: 2066: 2050: 2047: 2046: 2024: 2021: 2020: 2004: 2001: 2000: 1984: 1981: 1980: 1964: 1961: 1960: 1944: 1941: 1940: 1927: 1876: 1873: 1872: 1850: 1847: 1846: 1824: 1821: 1820: 1798: 1795: 1794: 1772: 1769: 1768: 1765:Polish notation 1748: 1745: 1744: 1728: 1725: 1724: 1708: 1705: 1704: 1701: 1665:classical logic 1622: 1619: 1618: 1602: 1599: 1598: 1597:is true unless 1576: 1573: 1572: 1552: 1549: 1548: 1535:(also known as 1525: 1484: 1451: 1422:Boolean algebra 1417:Predicate logic 1374: 1371: 1370: 1348: 1345: 1344: 1322: 1319: 1318: 1288: 1285: 1284: 1260: 1255: 1252: 1251: 1221: 1213: 1210: 1209: 1179: 1176: 1175: 1153: 1150: 1149: 1127: 1124: 1123: 1101: 1098: 1097: 1070: 1067: 1066: 1045: 1043: 1040: 1039: 1020: 1017: 1016: 997: 994: 993: 958: 956: 954: 951: 950: 928: 925: 924: 900: 895: 892: 891: 861: 858: 857: 835: 832: 831: 809: 806: 805: 772: 770: 768: 765: 764: 742: 739: 738: 716: 713: 712: 688: 683: 680: 679: 649: 646: 645: 623: 620: 619: 597: 594: 593: 563: 560: 559: 537: 534: 533: 511: 508: 507: 474: 471: 470: 448: 445: 444: 425: 422: 421: 399: 396: 395: 373: 370: 369: 344: 269:Post's lattices 268: 233: 230: 229: 194: 192: 189: 188: 153: 151: 148: 147: 98: 95: 94: 64: 61: 60: 35: 24: 17: 12: 11: 5: 6947: 6937: 6936: 6931: 6926: 6921: 6904: 6903: 6889: 6886: 6885: 6883: 6882: 6877: 6872: 6867: 6862: 6861: 6860: 6850: 6845: 6840: 6831: 6826: 6821: 6816: 6814:Abstract logic 6810: 6808: 6804: 6803: 6801: 6800: 6795: 6793:Turing machine 6790: 6785: 6780: 6775: 6770: 6765: 6764: 6763: 6758: 6753: 6748: 6743: 6733: 6731:Computable set 6728: 6723: 6718: 6713: 6707: 6705: 6699: 6698: 6696: 6695: 6690: 6685: 6680: 6675: 6670: 6665: 6660: 6659: 6658: 6653: 6648: 6638: 6633: 6628: 6626:Satisfiability 6623: 6618: 6613: 6612: 6611: 6601: 6600: 6599: 6589: 6588: 6587: 6582: 6577: 6572: 6567: 6557: 6556: 6555: 6550: 6543:Interpretation 6539: 6537: 6531: 6530: 6528: 6527: 6522: 6517: 6512: 6507: 6497: 6492: 6491: 6490: 6489: 6488: 6478: 6473: 6463: 6458: 6453: 6448: 6443: 6438: 6432: 6430: 6424: 6423: 6420: 6419: 6417: 6416: 6408: 6407: 6406: 6405: 6400: 6399: 6398: 6393: 6388: 6368: 6367: 6366: 6364:minimal axioms 6361: 6350: 6349: 6348: 6337: 6336: 6335: 6330: 6325: 6320: 6315: 6310: 6297: 6295: 6276: 6275: 6273: 6272: 6271: 6270: 6258: 6253: 6252: 6251: 6246: 6241: 6236: 6226: 6221: 6216: 6211: 6210: 6209: 6204: 6194: 6193: 6192: 6187: 6182: 6177: 6167: 6162: 6161: 6160: 6155: 6150: 6140: 6139: 6138: 6133: 6128: 6123: 6118: 6113: 6103: 6098: 6093: 6088: 6087: 6086: 6081: 6076: 6071: 6061: 6056: 6054:Formation rule 6051: 6046: 6045: 6044: 6039: 6029: 6028: 6027: 6017: 6012: 6007: 6002: 5996: 5990: 5973:Formal systems 5969: 5968: 5965: 5964: 5962: 5961: 5956: 5951: 5946: 5941: 5936: 5931: 5926: 5921: 5916: 5915: 5914: 5909: 5898: 5896: 5892: 5891: 5889: 5888: 5887: 5886: 5876: 5871: 5870: 5869: 5862:Large cardinal 5859: 5854: 5849: 5844: 5839: 5825: 5824: 5823: 5818: 5813: 5798: 5796: 5786: 5785: 5783: 5782: 5781: 5780: 5775: 5770: 5760: 5755: 5750: 5745: 5740: 5735: 5730: 5725: 5720: 5715: 5710: 5705: 5699: 5697: 5690: 5689: 5687: 5686: 5685: 5684: 5679: 5674: 5669: 5664: 5659: 5651: 5650: 5649: 5644: 5634: 5629: 5627:Extensionality 5624: 5622:Ordinal number 5619: 5609: 5604: 5603: 5602: 5591: 5585: 5579: 5578: 5575: 5574: 5572: 5571: 5566: 5561: 5556: 5551: 5546: 5541: 5540: 5539: 5529: 5528: 5527: 5514: 5512: 5506: 5505: 5503: 5502: 5501: 5500: 5495: 5490: 5480: 5475: 5470: 5465: 5460: 5455: 5449: 5447: 5441: 5440: 5438: 5437: 5432: 5427: 5422: 5417: 5412: 5407: 5406: 5405: 5395: 5390: 5385: 5380: 5375: 5370: 5364: 5362: 5353: 5347: 5346: 5344: 5343: 5338: 5333: 5328: 5323: 5318: 5306:Cantor's  5304: 5299: 5294: 5284: 5282: 5269: 5268: 5266: 5265: 5260: 5255: 5250: 5245: 5240: 5235: 5230: 5225: 5220: 5215: 5210: 5205: 5204: 5203: 5192: 5190: 5186: 5185: 5178: 5177: 5170: 5163: 5155: 5146: 5145: 5122: 5119: 5118: 5114: 5113: 5104: 5103: 5101: 5092: 5091: 5089: 5078: 5077: 5075: 5064: 5063: 5061: 5047: 5046: 5044: 5030: 5029: 5027: 5023:quantification 5019: 5014: 5013: 5011: 5007:quantification 5003: 4998: 4997: 4995: 4986: 4985: 4983: 4964: 4963: 4961: 4947: 4946: 4944: 4935: 4934: 4932: 4913: 4912: 4910: 4901: 4900: 4898: 4879: 4878: 4873: 4870: 4869: 4861: 4860: 4853: 4846: 4838: 4829: 4828: 4816: 4813: 4812: 4810: 4809: 4798: 4779: 4776: 4775: 4773: 4772: 4761: 4743: 4732: 4718: 4707: 4692:Nonimplication 4689: 4678: 4659: 4656: 4655: 4653: 4652: 4649:Digital buffer 4642: 4631: 4613: 4602: 4584: 4573: 4554: 4551: 4550: 4548: 4547: 4536: 4518: 4507: 4489: 4478: 4464: 4453: 4434: 4431: 4430: 4423: 4421: 4419: 4418: 4407: 4388: 4385: 4384: 4376: 4375: 4368: 4361: 4353: 4347: 4346: 4332:"Conditionals" 4327: 4313: 4312:External links 4310: 4309: 4308: 4292: 4274: 4260: 4235: 4232: 4229: 4228: 4193: 4179:10.1.1.13.1854 4172:(4): 481–530. 4156: 4127:(4): 608–631. 4109: 4102: 4069:"Conditionals" 4059: 4052: 4029:"Conditionals" 4014: 3995: 3986:"Conditionals" 3969: 3954: 3928: 3903: 3896: 3878: 3871: 3850: 3831: 3830: 3828: 3825: 3822: 3821: 3811: 3810: 3808: 3805: 3804: 3803: 3798: 3793: 3788: 3781: 3778: 3776: 3775: 3770: 3765: 3760: 3755: 3750: 3745: 3738: 3733: 3728: 3723: 3718: 3716:Boolean domain 3712: 3710: 3707: 3651:Grice's maxims 3641:proposed that 3620:vacuously true 3607: 3604: 3603: 3602: 3591: 3588: 3585: 3582: 3579: 3576: 3573: 3570: 3567: 3564: 3561: 3558: 3555: 3541: 3530: 3527: 3524: 3521: 3518: 3515: 3512: 3509: 3506: 3503: 3500: 3497: 3483: 3472: 3469: 3466: 3463: 3442: 3441: 3430: 3427: 3424: 3421: 3418: 3415: 3412: 3409: 3406: 3403: 3400: 3397: 3394: 3391: 3388: 3385: 3382: 3379: 3376: 3362: 3351: 3348: 3345: 3342: 3339: 3336: 3333: 3330: 3327: 3324: 3321: 3318: 3315: 3312: 3309: 3295: 3284: 3281: 3278: 3275: 3272: 3269: 3255: 3244: 3241: 3238: 3235: 3232: 3229: 3226: 3223: 3220: 3217: 3214: 3195: 3194: 3181: 3176: 3173: 3170: 3167: 3164: 3161: 3158: 3155: 3152: 3149: 3146: 3141: 3136: 3131: 3126: 3123: 3120: 3117: 3114: 3111: 3108: 3103: 3087: 3074: 3069: 3066: 3063: 3060: 3057: 3054: 3051: 3046: 3041: 3036: 3031: 3028: 3025: 3022: 3019: 3016: 3013: 3008: 2995: 2984: 2981: 2978: 2975: 2972: 2969: 2966: 2963: 2952: 2941: 2938: 2935: 2932: 2929: 2926: 2923: 2920: 2917: 2914: 2911: 2900: 2889: 2886: 2883: 2880: 2877: 2874: 2871: 2868: 2865: 2862: 2859: 2856: 2853: 2850: 2847: 2833: 2822: 2819: 2816: 2813: 2810: 2807: 2804: 2801: 2798: 2769: 2768: 2748: 2746: 2735: 2732: 2715: 2712: 2709: 2706: 2703: 2700: 2697: 2694: 2691: 2688: 2669: 2668: 2660: 2655: 2650: 2630: 2627: 2626: 2625: 2604: 2579:vacuous truths 2559: 2558: 2555: 2552: 2548: 2547: 2544: 2541: 2537: 2536: 2533: 2530: 2526: 2525: 2522: 2519: 2515: 2514: 2503: 2500: 2497: 2487: 2476: 2466: 2455: 2430: 2427: 2424: 2408: 2405: 2392: 2389: 2386: 2383: 2380: 2377: 2374: 2371: 2368: 2365: 2362: 2359: 2356: 2353: 2350: 2347: 2317: 2314: 2312: 2309: 2296: 2293: 2290: 2258: 2255: 2252: 2232: 2229: 2226: 2194: 2191: 2188: 2156: 2153: 2150: 2112: 2109: 2106: 2074: 2054: 2034: 2031: 2028: 2008: 1988: 1968: 1948: 1926: 1923: 1910: 1907: 1904: 1901: 1898: 1895: 1892: 1889: 1886: 1883: 1880: 1865:is termed the 1854: 1828: 1808: 1805: 1802: 1782: 1779: 1776: 1752: 1732: 1712: 1700: 1697: 1626: 1606: 1586: 1583: 1580: 1556: 1527: 1526: 1524: 1523: 1516: 1509: 1501: 1498: 1497: 1486: 1485: 1483: 1482: 1477: 1472: 1467: 1461: 1458: 1457: 1453: 1452: 1450: 1449: 1444: 1439: 1434: 1432:Truth function 1429: 1424: 1419: 1414: 1408: 1405: 1404: 1400: 1399: 1396: 1395: 1384: 1381: 1378: 1358: 1355: 1352: 1332: 1329: 1326: 1316: 1310: 1309: 1298: 1295: 1292: 1272: 1267: 1264: 1259: 1249: 1243: 1242: 1231: 1217: 1207: 1201: 1200: 1189: 1186: 1183: 1163: 1160: 1157: 1137: 1134: 1131: 1111: 1108: 1105: 1095: 1089: 1088: 1077: 1074: 1052: 1049: 1027: 1024: 1004: 1001: 991: 985: 984: 971: 967: 964: 961: 938: 935: 932: 912: 907: 904: 899: 889: 883: 882: 871: 868: 865: 845: 842: 839: 819: 816: 813: 803: 799: 798: 785: 781: 778: 775: 752: 749: 746: 726: 723: 720: 700: 695: 692: 687: 677: 671: 670: 659: 656: 653: 633: 630: 627: 607: 604: 601: 591: 585: 584: 573: 570: 567: 547: 544: 541: 521: 518: 515: 505: 499: 498: 487: 484: 481: 478: 458: 455: 452: 432: 429: 409: 406: 403: 383: 380: 377: 367: 357: 356: 346: 345: 343: 342: 335: 328: 320: 317: 316: 313: 309: 308: 305: 299: 298: 295: 289: 288: 285: 281: 280: 277: 273: 272: 264: 263: 252: 249: 246: 243: 240: 237: 227: 221: 220: 209: 206: 201: 198: 186: 180: 179: 168: 165: 160: 157: 145: 139: 138: 134: 133: 126: 120: 119: 108: 105: 102: 92: 86: 85: 74: 71: 68: 58: 54: 53: 45: 44: 15: 9: 6: 4: 3: 2: 6946: 6935: 6932: 6930: 6927: 6925: 6922: 6920: 6917: 6916: 6914: 6901: 6900: 6895: 6887: 6881: 6878: 6876: 6873: 6871: 6868: 6866: 6863: 6859: 6856: 6855: 6854: 6851: 6849: 6846: 6844: 6841: 6839: 6835: 6832: 6830: 6827: 6825: 6822: 6820: 6817: 6815: 6812: 6811: 6809: 6805: 6799: 6796: 6794: 6791: 6789: 6788:Recursive set 6786: 6784: 6781: 6779: 6776: 6774: 6771: 6769: 6766: 6762: 6759: 6757: 6754: 6752: 6749: 6747: 6744: 6742: 6739: 6738: 6737: 6734: 6732: 6729: 6727: 6724: 6722: 6719: 6717: 6714: 6712: 6709: 6708: 6706: 6704: 6700: 6694: 6691: 6689: 6686: 6684: 6681: 6679: 6676: 6674: 6671: 6669: 6666: 6664: 6661: 6657: 6654: 6652: 6649: 6647: 6644: 6643: 6642: 6639: 6637: 6634: 6632: 6629: 6627: 6624: 6622: 6619: 6617: 6614: 6610: 6607: 6606: 6605: 6602: 6598: 6597:of arithmetic 6595: 6594: 6593: 6590: 6586: 6583: 6581: 6578: 6576: 6573: 6571: 6568: 6566: 6563: 6562: 6561: 6558: 6554: 6551: 6549: 6546: 6545: 6544: 6541: 6540: 6538: 6536: 6532: 6526: 6523: 6521: 6518: 6516: 6513: 6511: 6508: 6505: 6504:from ZFC 6501: 6498: 6496: 6493: 6487: 6484: 6483: 6482: 6479: 6477: 6474: 6472: 6469: 6468: 6467: 6464: 6462: 6459: 6457: 6454: 6452: 6449: 6447: 6444: 6442: 6439: 6437: 6434: 6433: 6431: 6429: 6425: 6415: 6414: 6410: 6409: 6404: 6403:non-Euclidean 6401: 6397: 6394: 6392: 6389: 6387: 6386: 6382: 6381: 6379: 6376: 6375: 6373: 6369: 6365: 6362: 6360: 6357: 6356: 6355: 6351: 6347: 6344: 6343: 6342: 6338: 6334: 6331: 6329: 6326: 6324: 6321: 6319: 6316: 6314: 6311: 6309: 6306: 6305: 6303: 6299: 6298: 6296: 6291: 6285: 6280:Example  6277: 6269: 6264: 6263: 6262: 6259: 6257: 6254: 6250: 6247: 6245: 6242: 6240: 6237: 6235: 6232: 6231: 6230: 6227: 6225: 6222: 6220: 6217: 6215: 6212: 6208: 6205: 6203: 6200: 6199: 6198: 6195: 6191: 6188: 6186: 6183: 6181: 6178: 6176: 6173: 6172: 6171: 6168: 6166: 6163: 6159: 6156: 6154: 6151: 6149: 6146: 6145: 6144: 6141: 6137: 6134: 6132: 6129: 6127: 6124: 6122: 6119: 6117: 6114: 6112: 6109: 6108: 6107: 6104: 6102: 6099: 6097: 6094: 6092: 6089: 6085: 6082: 6080: 6077: 6075: 6072: 6070: 6067: 6066: 6065: 6062: 6060: 6057: 6055: 6052: 6050: 6047: 6043: 6040: 6038: 6037:by definition 6035: 6034: 6033: 6030: 6026: 6023: 6022: 6021: 6018: 6016: 6013: 6011: 6008: 6006: 6003: 6001: 5998: 5997: 5994: 5991: 5989: 5985: 5980: 5974: 5970: 5960: 5957: 5955: 5952: 5950: 5947: 5945: 5942: 5940: 5937: 5935: 5932: 5930: 5927: 5925: 5924:Kripke–Platek 5922: 5920: 5917: 5913: 5910: 5908: 5905: 5904: 5903: 5900: 5899: 5897: 5893: 5885: 5882: 5881: 5880: 5877: 5875: 5872: 5868: 5865: 5864: 5863: 5860: 5858: 5855: 5853: 5850: 5848: 5845: 5843: 5840: 5837: 5833: 5829: 5826: 5822: 5819: 5817: 5814: 5812: 5809: 5808: 5807: 5803: 5800: 5799: 5797: 5795: 5791: 5787: 5779: 5776: 5774: 5771: 5769: 5768:constructible 5766: 5765: 5764: 5761: 5759: 5756: 5754: 5751: 5749: 5746: 5744: 5741: 5739: 5736: 5734: 5731: 5729: 5726: 5724: 5721: 5719: 5716: 5714: 5711: 5709: 5706: 5704: 5701: 5700: 5698: 5696: 5691: 5683: 5680: 5678: 5675: 5673: 5670: 5668: 5665: 5663: 5660: 5658: 5655: 5654: 5652: 5648: 5645: 5643: 5640: 5639: 5638: 5635: 5633: 5630: 5628: 5625: 5623: 5620: 5618: 5614: 5610: 5608: 5605: 5601: 5598: 5597: 5596: 5593: 5592: 5589: 5586: 5584: 5580: 5570: 5567: 5565: 5562: 5560: 5557: 5555: 5552: 5550: 5547: 5545: 5542: 5538: 5535: 5534: 5533: 5530: 5526: 5521: 5520: 5519: 5516: 5515: 5513: 5511: 5507: 5499: 5496: 5494: 5491: 5489: 5486: 5485: 5484: 5481: 5479: 5476: 5474: 5471: 5469: 5466: 5464: 5461: 5459: 5456: 5454: 5451: 5450: 5448: 5446: 5445:Propositional 5442: 5436: 5433: 5431: 5428: 5426: 5423: 5421: 5418: 5416: 5413: 5411: 5408: 5404: 5401: 5400: 5399: 5396: 5394: 5391: 5389: 5386: 5384: 5381: 5379: 5376: 5374: 5373:Logical truth 5371: 5369: 5366: 5365: 5363: 5361: 5357: 5354: 5352: 5348: 5342: 5339: 5337: 5334: 5332: 5329: 5327: 5324: 5322: 5319: 5317: 5313: 5309: 5305: 5303: 5300: 5298: 5295: 5293: 5289: 5286: 5285: 5283: 5281: 5275: 5270: 5264: 5261: 5259: 5256: 5254: 5251: 5249: 5246: 5244: 5241: 5239: 5236: 5234: 5231: 5229: 5226: 5224: 5221: 5219: 5216: 5214: 5211: 5209: 5206: 5202: 5199: 5198: 5197: 5194: 5193: 5191: 5187: 5183: 5176: 5171: 5169: 5164: 5162: 5157: 5156: 5153: 5143: 5138: 5132: 5120: 5111: 5107: 5102: 5099: 5095: 5090: 5087: 5081: 5076: 5073: 5067: 5062: 5059: 5058:contradiction 5054: 5050: 5045: 5042: 5037: 5033: 5028: 5024: 5017: 5012: 5008: 5001: 4996: 4993: 4989: 4984: 4981: 4977: 4972: 4967: 4962: 4959: 4954: 4950: 4945: 4942: 4938: 4933: 4930: 4926: 4921: 4916: 4911: 4908: 4904: 4899: 4896: 4892: 4887: 4882: 4877: 4876: 4871: 4867: 4859: 4854: 4852: 4847: 4845: 4840: 4839: 4836: 4826: 4814: 4788: 4784: 4783:Contradiction 4781: 4780: 4777: 4759: 4751: 4747: 4744: 4730: 4722: 4719: 4705: 4697: 4693: 4690: 4668: 4664: 4661: 4660: 4657: 4650: 4646: 4643: 4621: 4617: 4616:Biconditional 4614: 4600: 4592: 4588: 4585: 4563: 4559: 4556: 4555: 4552: 4534: 4526: 4522: 4519: 4497: 4493: 4490: 4468: 4465: 4443: 4439: 4436: 4435: 4432: 4427: 4397: 4393: 4390: 4389: 4386: 4382: 4374: 4369: 4367: 4362: 4360: 4355: 4354: 4351: 4343: 4342: 4337: 4333: 4328: 4325: 4320: 4316: 4315: 4306: 4302: 4301: 4296: 4293: 4290: 4286: 4282: 4278: 4275: 4272: 4268: 4264: 4261: 4258: 4254: 4250: 4246: 4242: 4238: 4237: 4224: 4220: 4215: 4210: 4206: 4205: 4197: 4189: 4185: 4180: 4175: 4171: 4167: 4160: 4152: 4148: 4144: 4140: 4135: 4130: 4126: 4122: 4121: 4113: 4105: 4099: 4094: 4089: 4085: 4081: 4077: 4070: 4063: 4055: 4053:9781118972090 4049: 4045: 4041: 4037: 4030: 4023: 4021: 4019: 4010: 4006: 3999: 3991: 3987: 3980: 3978: 3976: 3974: 3965: 3958: 3943: 3939: 3932: 3914: 3907: 3899: 3897:0-674-32449-8 3893: 3889: 3882: 3874: 3868: 3864: 3860: 3854: 3846: 3839: 3837: 3832: 3816: 3812: 3802: 3799: 3797: 3794: 3792: 3789: 3787: 3784: 3783: 3774: 3771: 3769: 3766: 3764: 3761: 3759: 3756: 3754: 3751: 3749: 3748:Logical graph 3746: 3744: 3743: 3739: 3737: 3734: 3732: 3729: 3727: 3726:Boolean logic 3724: 3722: 3719: 3717: 3714: 3713: 3706: 3703: 3698: 3696: 3695:causal models 3692: 3688: 3684: 3680: 3676: 3672: 3668: 3664: 3660: 3656: 3652: 3648: 3644: 3640: 3639:Frank Jackson 3636: 3631: 3629: 3625: 3621: 3617: 3613: 3586: 3577: 3571: 3565: 3559: 3553: 3545: 3542: 3525: 3519: 3513: 3507: 3501: 3495: 3487: 3484: 3470: 3464: 3461: 3453: 3450: 3449: 3448: 3446: 3425: 3419: 3413: 3407: 3401: 3395: 3392: 3383: 3380: 3377: 3366: 3363: 3349: 3343: 3340: 3334: 3328: 3322: 3316: 3310: 3299: 3296: 3282: 3276: 3273: 3270: 3259: 3256: 3242: 3233: 3230: 3227: 3221: 3218: 3212: 3204: 3203: 3202: 3200: 3171: 3165: 3153: 3147: 3134: 3121: 3115: 3106: 3091: 3088: 3064: 3058: 3049: 3039: 3026: 3020: 3011: 2996: 2982: 2979: 2976: 2970: 2967: 2961: 2953: 2939: 2933: 2930: 2927: 2921: 2915: 2901: 2887: 2878: 2875: 2872: 2866: 2860: 2854: 2845: 2837: 2836:Import-export 2834: 2820: 2811: 2805: 2802: 2796: 2788: 2787: 2786: 2784: 2780: 2776: 2765: 2762:February 2021 2756: 2752: 2749:This section 2747: 2744: 2740: 2739: 2731: 2729: 2713: 2710: 2707: 2695: 2689: 2678: 2674: 2667: 2666: 2661: 2659: 2656: 2654: 2651: 2649: 2648: 2644: 2643: 2642: 2640: 2636: 2623: 2621: 2617: 2610: 2605: 2602: 2600: 2596: 2589: 2584: 2583: 2582: 2580: 2575: 2571: 2567:is false and 2556: 2553: 2550: 2549: 2545: 2542: 2539: 2538: 2534: 2531: 2528: 2527: 2523: 2520: 2517: 2516: 2501: 2495: 2488: 2474: 2467: 2453: 2446: 2445: 2442: 2428: 2422: 2414: 2404: 2390: 2387: 2384: 2378: 2372: 2366: 2363: 2354: 2351: 2345: 2337: 2333: 2330: 2326: 2323: 2308: 2294: 2288: 2280: 2276: 2272: 2256: 2250: 2230: 2227: 2224: 2216: 2212: 2208: 2192: 2189: 2186: 2178: 2174: 2170: 2154: 2151: 2148: 2140: 2136: 2132: 2131: 2126: 2110: 2104: 2096: 2092: 2088: 2072: 2052: 2032: 2029: 2026: 2006: 1986: 1966: 1946: 1938: 1934: 1933: 1922: 1905: 1899: 1887: 1881: 1870: 1869: 1852: 1844: 1843: 1826: 1806: 1800: 1780: 1777: 1774: 1766: 1730: 1696: 1694: 1690: 1686: 1683:. Due to the 1682: 1678: 1674: 1670: 1666: 1661: 1659: 1658: 1652: 1648: 1647: 1646:modus tollens 1642: 1641: 1624: 1604: 1584: 1578: 1570: 1546: 1542: 1538: 1534: 1522: 1517: 1515: 1510: 1508: 1503: 1502: 1500: 1499: 1496: 1488: 1487: 1481: 1478: 1476: 1473: 1471: 1468: 1466: 1465:Digital logic 1463: 1462: 1460: 1459: 1455: 1454: 1448: 1447:Scope (logic) 1445: 1443: 1440: 1438: 1435: 1433: 1430: 1428: 1425: 1423: 1420: 1418: 1415: 1413: 1410: 1409: 1407: 1406: 1402: 1401: 1382: 1376: 1356: 1353: 1350: 1330: 1324: 1317: 1315: 1312: 1311: 1296: 1293: 1290: 1270: 1265: 1262: 1257: 1250: 1248: 1245: 1244: 1229: 1215: 1208: 1206: 1203: 1202: 1187: 1184: 1181: 1161: 1158: 1155: 1135: 1132: 1129: 1109: 1106: 1103: 1096: 1094: 1091: 1090: 1075: 1072: 1047: 1025: 1022: 1002: 992: 990: 987: 986: 965: 962: 959: 936: 930: 910: 902: 897: 890: 888: 885: 884: 869: 866: 863: 843: 840: 837: 817: 814: 811: 804: 802:nonequivalent 801: 800: 779: 776: 773: 750: 747: 744: 724: 718: 698: 690: 685: 678: 676: 673: 672: 657: 651: 631: 628: 625: 605: 599: 592: 590: 587: 586: 571: 565: 545: 539: 519: 516: 513: 506: 504: 501: 500: 485: 476: 456: 450: 430: 427: 407: 404: 401: 381: 378: 375: 368: 366: 363: 362: 359: 358: 355: 352: 351: 341: 336: 334: 329: 327: 322: 321: 318: 314: 310: 306: 304: 300: 296: 294: 290: 286: 282: 278: 274: 271: 265: 250: 247: 244: 241: 238: 235: 228: 226: 222: 207: 204: 196: 187: 185: 181: 166: 163: 155: 146: 144: 140: 135: 131: 127: 125: 121: 103: 93: 91: 87: 72: 66: 59: 55: 51: 46: 41: 33: 29: 22: 6924:Conditionals 6890: 6688:Ultraproduct 6535:Model theory 6500:Independence 6436:Formal proof 6428:Proof theory 6411: 6384: 6341:real numbers 6313:second-order 6224:Substitution 6125: 6101:Metalanguage 6042:conservative 6015:Axiom schema 5959:Constructive 5929:Morse–Kelley 5895:Set theories 5874:Aleph number 5867:inaccessible 5773:Grothendieck 5657:intersection 5544:Higher-order 5532:Second-order 5478:Truth tables 5435:Venn diagram 5218:Formal proof 4970: 4952: 4940: 4919: 4885: 4663:Joint denial 4587:Exclusive or 4491: 4339: 4304: 4298: 4280: 4266: 4240: 4203: 4196: 4169: 4165: 4159: 4124: 4118: 4112: 4093:1721.1/95781 4075: 4062: 4035: 4008: 3998: 3989: 3963: 3957: 3946:. Retrieved 3941: 3931: 3920:. Retrieved 3906: 3887: 3881: 3862: 3853: 3844: 3815: 3780:Conditionals 3763:Peirce's law 3742:Laws of Form 3740: 3699: 3678: 3674: 3670: 3666: 3632: 3609: 3443: 3298:Transitivity 3196: 2772: 2759: 2755:adding to it 2750: 2670: 2664: 2647:Modus ponens 2645: 2632: 2613: 2608: 2592: 2587: 2573: 2569: 2562: 2410: 2319: 2278: 2274: 2214: 2210: 2176: 2172: 2138: 2134: 2128: 2094: 2090: 1930: 1928: 1866: 1840: 1702: 1662: 1656: 1644: 1640:modus ponens 1638: 1617:is true and 1536: 1532: 1530: 1456:Applications 588: 284:1-preserving 276:0-preserving 137:Normal forms 6798:Type theory 6746:undecidable 6678:Truth value 6565:equivalence 6244:non-logical 5857:Enumeration 5847:Isomorphism 5794:cardinality 5778:Von Neumann 5743:Ultrafilter 5708:Uncountable 5642:equivalence 5559:Quantifiers 5549:Fixed-point 5518:First-order 5398:Consistency 5383:Proposition 5360:Traditional 5331:Lindström's 5321:Compactness 5263:Type theory 5208:Cardinality 5021:existential 4746:Conjunction 4696:NIMPLY gate 4521:Disjunction 4492:Implication 4300:Philosophia 4277:Quine, W.V. 4259:, NY, 2003. 3683:modal logic 3452:Reflexivity 3445:Tautologies 3199:entailments 2954:Or-and-if: 2779:conjunction 2775:disjunction 2635:deductively 2616:Marie Curie 2595:Marie Curie 2413:truth table 2407:Truth table 2336:truth table 2311:Definitions 1569:interpreted 1427:Truth table 184:Conjunctive 143:Disjunctive 90:Truth table 6913:Categories 6609:elementary 6302:arithmetic 6170:Quantifier 6148:functional 6020:Expression 5738:Transitive 5682:identities 5667:complement 5600:hereditary 5583:Set theory 4496:IMPLY gate 3948:2022-08-10 3922:2022-08-10 3827:References 2663:Classical 1868:consequent 1842:antecedent 1655:classical 503:equivalent 124:Logic gate 57:Definition 6934:Semantics 6880:Supertask 6783:Recursion 6741:decidable 6575:saturated 6553:of models 6476:deductive 6471:axiomatic 6391:Hilbert's 6378:Euclidean 6359:canonical 6282:axiomatic 6214:Signature 6143:Predicate 6032:Extension 5954:Ackermann 5879:Operation 5758:Universal 5748:Recursive 5723:Singleton 5718:Inhabited 5703:Countable 5693:Types of 5677:power set 5647:partition 5564:Predicate 5510:Predicate 5425:Syllogism 5415:Soundness 5388:Inference 5378:Tautology 5280:paradoxes 5098:therefore 5086:therefore 5041:tautology 5005:universal 4797:⊥ 4760:∧ 4731:↚ 4706:↛ 4677:↓ 4645:Statement 4630:↔ 4620:XNOR gate 4572:¬ 4535:∨ 4506:→ 4477:← 4452:↑ 4442:NAND gate 4406:⊤ 4392:Tautology 4289:Cambridge 4271:Blackwell 4223:246924881 4174:CiteSeerX 4129:CiteSeerX 3643:pragmatic 3584:¬ 3581:→ 3572:∨ 3563:→ 3554:⊨ 3523:→ 3514:∨ 3505:→ 3496:⊨ 3468:→ 3462:⊨ 3423:→ 3414:∧ 3405:→ 3396:⊨ 3390:→ 3381:∨ 3347:→ 3341:⊨ 3332:→ 3323:∧ 3314:→ 3280:→ 3274:⊨ 3268:¬ 3240:→ 3231:∧ 3222:⊨ 3216:→ 3169:→ 3160:→ 3151:→ 3135:≡ 3119:→ 3110:→ 3062:→ 3053:→ 3040:≡ 3024:→ 3015:→ 2980:∨ 2974:¬ 2971:≡ 2965:→ 2937:¬ 2934:∧ 2928:≡ 2919:→ 2910:¬ 2885:→ 2876:∧ 2867:≡ 2858:→ 2849:→ 2818:¬ 2815:→ 2809:¬ 2806:≡ 2800:→ 2711:∨ 2705:¬ 2702:⇒ 2693:→ 2606:... with 2585:... with 2499:→ 2426:→ 2388:∨ 2382:¬ 2379:≡ 2370:¬ 2367:∧ 2358:¬ 2355:≡ 2349:→ 2322:classical 2316:Semantics 2307:in 1954. 2292:⇒ 2254:→ 2228:⊃ 2190:⊃ 2152:⊃ 2123:in 1918. 2108:→ 2030:⊃ 1903:→ 1894:→ 1885:→ 1804:→ 1751:⇒ 1731:⊃ 1711:→ 1582:→ 1555:→ 1541:operation 1380:← 1354:⊂ 1328:⇐ 1294:⊕ 1266:_ 1263:∨ 1185:∥ 1159:∣ 1107:∨ 1073:∼ 1051:¯ 1023:− 1000:¬ 970:¯ 934:↓ 906:¯ 903:∨ 867:↮ 784:¯ 777:⋅ 748:∣ 722:↑ 694:¯ 691:∧ 655:→ 629:⊃ 603:⇒ 569:⇋ 543:⇔ 517:≡ 483:& 480:& 454:& 405:⋅ 379:∧ 312:Self-dual 245:⊕ 239:⊕ 200:¯ 159:¯ 70:→ 6865:Logicism 6858:timeline 6834:Concrete 6693:Validity 6663:T-schema 6656:Kripke's 6651:Tarski's 6646:semantic 6636:Strength 6585:submodel 6580:spectrum 6548:function 6396:Tarski's 6385:Elements 6372:geometry 6328:Robinson 6249:variable 6234:function 6207:spectrum 6197:Sentence 6153:variable 6096:Language 6049:Relation 6010:Automata 6000:Alphabet 5984:language 5838:-jection 5816:codomain 5802:Function 5763:Universe 5733:Infinite 5637:Relation 5420:Validity 5410:Argument 5308:theorem, 5084:entails, 5070:entails, 4958:superset 4750:AND gate 4667:NOR gate 4601:↮ 4591:XOR gate 4562:NOT gate 4558:Negation 4279:(1982), 3861:(2015). 3709:See also 3486:Totality 2783:negation 2271:Bourbaki 1935:(1889), 1699:Notation 1679:and the 1539:) is an 1495:Category 1314:converse 841:⇎ 815:≢ 293:Monotone 6807:Related 6604:Diagram 6502: ( 6481:Hilbert 6466:Systems 6461:Theorem 6339:of the 6284:systems 6064:Formula 6059:Grammar 5975: ( 5919:General 5632:Forcing 5617:Element 5537:Monadic 5312:paradox 5253:Theorem 5189:General 5110:because 4974:  4953:implies 4941:implies 4923:  4889:  4864:Common 4752:)  4748: ( 4698:)  4694: ( 4669:)  4665: ( 4647: ( 4622:)  4618: ( 4593:)  4589: ( 4564:)  4560: ( 4527:)  4525:OR gate 4523: ( 4498:)  4494: ( 4444:)  4440: ( 4379:Common 4338:(ed.). 4257:Mineola 4249:Norwell 4151:2912209 3669:, then 2591:false: 2320:From a 2277:, then 2213:, then 2207:Heyting 2175:, then 2169:Gentzen 2137:, then 2125:Russell 2093:, then 2087:Hilbert 1959:, then 1925:History 589:implies 6570:finite 6333:Skolem 6286:  6261:Theory 6229:Symbol 6219:String 6202:atomic 6079:ground 6074:closed 6069:atomic 6025:ground 5988:syntax 5884:binary 5811:domain 5728:Finite 5493:finite 5351:Logics 5310:  5258:Theory 5072:proves 4968:  4917:  4883:  4789:  4723:  4469:  4398:  4245:Kluwer 4221:  4176:  4149:  4131:  4100:  4050:  3894:  3869:  3693:, and 3647:denote 2612:true: 2329:binary 1653:, and 1227:  1219:  303:Affine 6560:Model 6308:Peano 6165:Proof 6005:Arity 5934:Naive 5821:image 5753:Fuzzy 5713:Empty 5662:union 5607:Class 5248:Model 5238:Lemma 5196:Axiom 5053:false 4891:& 4787:False 4334:. In 4291:, MA. 4219:S2CID 4147:S2CID 4072:(PDF) 4032:(PDF) 3916:(PDF) 3807:Notes 2773:When 2281:" as 2217:" as 2179:" as 2141:" as 2097:" as 1979:" as 1937:Peano 1545:logic 43:IMPLY 6683:Type 6486:list 6290:list 6267:list 6256:Term 6190:rank 6084:open 5978:list 5790:Maps 5695:sets 5554:Free 5524:list 5274:list 5201:list 5036:true 4992:nand 4396:True 4098:ISBN 4048:ISBN 3892:ISBN 3867:ISBN 3677:and 3657:and 3637:and 2781:and 2614:"If 2593:"If 2411:The 1845:and 1743:and 1531:The 1223:XNOR 1205:XNOR 675:NAND 104:1011 6370:of 6352:of 6300:of 5832:Sur 5806:Map 5613:Ur- 5595:Set 4980:iff 4929:not 4895:and 4209:doi 4184:doi 4139:doi 4125:101 4088:hdl 4080:doi 4040:doi 3614:in 2757:. 2415:of 2045:as 1929:In 1691:in 1567:is 1247:XOR 989:NOT 887:NOR 365:AND 287:yes 30:or 6915:: 6756:NP 6380:: 6374:: 6304:: 5981:), 5836:Bi 5828:In 4971:or 4920:or 4907:or 4886:or 4303:, 4287:, 4269:, 4255:, 4217:. 4182:. 4170:28 4168:. 4145:. 4137:. 4123:. 4096:. 4086:. 4046:. 4017:^ 3972:^ 3940:. 3835:^ 3697:. 3689:, 3685:, 3546:: 3488:: 3454:: 3367:: 3300:: 3260:: 3201:: 3092:: 2838:: 2777:, 2730:. 2641:. 2572:→ 2441:: 2403:. 2205:. 2085:. 2065:Ɔ 1999:Ɔ 1921:. 1695:. 1660:. 1649:, 1643:, 1369:, 1343:, 1283:, 1174:, 1148:, 1122:, 1093:OR 1065:, 1038:, 1015:, 949:, 923:, 856:, 830:, 763:, 737:, 711:, 644:, 618:, 558:, 532:, 469:, 443:, 420:, 394:, 315:no 307:no 297:no 279:no 6836:/ 6751:P 6506:) 6292:) 6288:( 6185:∀ 6180:! 6175:∃ 6136:= 6131:↔ 6126:→ 6121:∧ 6116:∨ 6111:¬ 5834:/ 5830:/ 5804:/ 5615:) 5611:( 5498:∞ 5488:3 5276:) 5174:e 5167:t 5160:v 5106:∵ 5094:∴ 5080:⊨ 5066:⊢ 5055:, 5049:⊥ 5038:, 5032:⊤ 5016:∃ 5000:∀ 4988:| 4976:≡ 4966:↔ 4955:, 4949:⊃ 4937:→ 4925:~ 4915:¬ 4903:∨ 4881:∧ 4857:e 4850:t 4843:v 4785:/ 4651:) 4394:/ 4372:e 4365:t 4358:v 4344:. 4305:5 4273:. 4225:. 4211:: 4190:. 4186:: 4153:. 4141:: 4106:. 4090:: 4082:: 4056:. 4042:: 4011:. 3951:. 3925:. 3900:. 3875:. 3847:. 3679:Q 3675:P 3671:Q 3667:P 3590:) 3587:Q 3578:P 3575:( 3569:) 3566:Q 3560:P 3557:( 3529:) 3526:P 3520:Q 3517:( 3511:) 3508:Q 3502:P 3499:( 3471:P 3465:P 3429:) 3426:R 3420:Q 3417:( 3411:) 3408:R 3402:P 3399:( 3393:R 3387:) 3384:Q 3378:P 3375:( 3350:R 3344:P 3338:) 3335:R 3329:Q 3326:( 3320:) 3317:Q 3311:P 3308:( 3283:Q 3277:P 3271:P 3243:Q 3237:) 3234:R 3228:P 3225:( 3219:Q 3213:P 3180:) 3175:) 3172:Q 3166:R 3163:( 3157:) 3154:P 3148:R 3145:( 3140:( 3130:) 3125:) 3122:Q 3116:P 3113:( 3107:R 3102:( 3073:) 3068:) 3065:R 3059:P 3056:( 3050:Q 3045:( 3035:) 3030:) 3027:R 3021:Q 3018:( 3012:P 3007:( 2983:Q 2977:P 2968:Q 2962:P 2940:Q 2931:P 2925:) 2922:Q 2916:P 2913:( 2888:R 2882:) 2879:Q 2873:P 2870:( 2864:) 2861:R 2855:Q 2852:( 2846:P 2821:P 2812:Q 2803:Q 2797:P 2764:) 2760:( 2714:B 2708:A 2699:) 2696:B 2690:A 2687:( 2624:. 2609:B 2603:, 2588:B 2574:B 2570:A 2565:A 2557:T 2554:T 2551:T 2546:F 2543:F 2540:T 2535:T 2532:T 2529:F 2524:T 2521:F 2518:F 2502:B 2496:A 2475:B 2454:A 2429:B 2423:A 2391:B 2385:A 2376:) 2373:B 2364:A 2361:( 2352:B 2346:A 2295:B 2289:A 2279:B 2275:A 2257:B 2251:A 2231:B 2225:A 2215:B 2211:A 2193:B 2187:A 2177:B 2173:A 2155:B 2149:A 2139:B 2135:A 2111:B 2105:A 2095:B 2091:A 2073:B 2053:A 2033:B 2027:A 2007:B 1987:A 1967:B 1947:A 1909:) 1906:s 1900:r 1897:( 1891:) 1888:q 1882:p 1879:( 1853:q 1827:p 1807:q 1801:p 1781:q 1778:p 1775:C 1625:Q 1605:P 1585:Q 1579:P 1520:e 1513:t 1506:v 1383:B 1377:A 1357:B 1351:A 1331:B 1325:A 1297:B 1291:A 1271:B 1258:A 1230:B 1216:A 1188:B 1182:A 1162:B 1156:A 1136:B 1133:+ 1130:A 1110:B 1104:A 1076:A 1048:A 1026:A 1003:A 966:B 963:+ 960:A 937:B 931:A 911:B 898:A 870:B 864:A 844:B 838:A 818:B 812:A 780:B 774:A 751:B 745:A 725:B 719:A 699:B 686:A 658:B 652:A 632:B 626:A 606:B 600:A 572:B 566:A 546:B 540:A 520:B 514:A 486:B 477:A 457:B 451:A 431:B 428:A 408:B 402:A 382:B 376:A 339:e 332:t 325:v 251:y 248:x 242:x 236:1 208:y 205:+ 197:x 167:y 164:+ 156:x 107:) 101:( 73:y 67:x 34:. 23:.

Index

Conditional statement
Material inference
Material implication (rule of inference)
Venn diagram of Material conditional
Truth table
Logic gate

Disjunctive
Conjunctive
Zhegalkin polynomial
Post's lattices
Monotone
Affine
v
t
e
Logical connectives
AND
equivalent
implies
NAND
NOR
NOT
OR
XNOR
XOR
converse
Propositional calculus
Predicate logic
Boolean algebra

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