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Converse (logic)

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However, the converse of a statement with mutually inclusive terms remains true, given the truth of the original proposition. This is equivalent to saying that the converse of a definition is true. Thus, the statement "If I am a triangle, then I am a three-sided polygon" is logically equivalent to
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proposition "All cats are mammals", the converse "All mammals are cats" is obviously false. However, the weaker statement "Some mammals are cats" is true. Logicians define conversion
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In practice, when determining the converse of a mathematical theorem, aspects of the antecedent may be taken as establishing context. That is, the converse of "Given P, if Q then R
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For example, consider the true statement "If I am a human, then I am mortal." The converse of that statement is "If I am mortal, then I am a human," which is not necessarily
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propositions can be expressed by the restriction that "No term must be distributed in the converse which is not distributed in the convertend." For
2977: 1184: 17: 1366:"If I am a three-sided polygon, then I am a triangle," because the definition of "triangle" is "three-sided polygon". 2970: 2673:. It is therefore clear that the categorical converse is closely related to the implicational converse, and that 2251: 1223:
of a categorical or implicational statement is the result of reversing its two constituent statements. For the
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The "exposita" is more usually called the "convertend". In its simple form, conversion is valid only for
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propositions, the subject is distributed while the predicate is not, and so the inference from an
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In traditional logic, the process of switching the subject term with the predicate term is called
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to be the process of producing this weaker statement. Inference from a statement to its converse
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Converse implication is logically equivalent to the disjunction of
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are not logically equivalent, unless both terms imply each other:
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statement to its converse is not valid. As an example, for the
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was proved in 1912, but its converse was proved only in 1997.
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The Science of Logic: or, An Analysis of the Laws of Thought
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is also true), then affirming the consequent will be valid.
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Going from a statement to its converse is the fallacy of
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says nothing about the truth of its converse, unless the
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In mathematics, the converse of a theorem of the form
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Reverse of a categorical or hypothetical proposition
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The World and Language in Wittgenstein's Philosophy
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Hacker (1991), 2763:, 2nd ed., Cambridge University Press: "converse". 2665: 2395: 2369: 2315: 2237: 2198: 2160: 2135: 2078: 2056: 2034: 1993: 1936: 1910: 1888: 1866: 1775: 1746: 1715: 1691: 1670: 1648: 1626: 1596: 1573: 1469: 1442: 1415: 1394: 1296:The white area shows where the statement is false. 1286: 1067: 1041: 1015: 981: 955: 914: 872: 846: 820: 794: 760: 737: 710: 687: 656: 621: 595: 554: 528: 502: 470: 435: 409: 383: 342: 316: 290: 256: 230: 204: 170: 141: 115: 92: 66: 1795:In natural language, this could be rendered "not 3442: 2985: 2609:"Some mammals are unicorns" is clearly false. 2971: 2570:propositions, both subject and predicate are 1192: 2310: 2268: 2014:(Book I, Proposition 48), can be stated as: 2558:The validity of simple conversion only for 2978: 2964: 2800:"The Four Vertex Theorem and its Converse" 2797: 2316:{\displaystyle R^{T}=\{(b,a):(a,b)\in R\}} 1199: 1185: 2421:Categorical proposition § Conversion 2173: 1256: 2177: 1806: 1260: 2414: 2182:Converse a simple mathematical relation 1547:and its converse are equivalent (i.e., 529:{\displaystyle A\not \Leftrightarrow B} 14: 3443: 2761:The Cambridge Dictionary of Philosophy 2666:{\displaystyle \forall x.S(x)\to P(x)} 2147:the angle opposite the side of length 1923:the angle opposite the side of length 956:{\displaystyle A{\underline {\lor }}B} 471:{\displaystyle {\overline {A\cdot B}}} 384:{\displaystyle A{\overline {\land }}B} 3213:{\displaystyle \not \leftrightarrow } 2959: 2601:is generally valid. However, as with 2238:{\displaystyle R\subseteq A\times B,} 596:{\displaystyle A{\overline {\lor }}B} 257:{\displaystyle A\leftrightharpoons B} 2798:Shonkwiler, Clay (October 6, 2006). 2007:The converse, which also appears in 2753: 915:{\displaystyle A\ {\text{XNOR}}\ B} 555:{\displaystyle A\nleftrightarrow B} 24: 3403: 3178: 3012: 2942:. MacMillan, 1979, fifth edition. 2912: 2772: 2627: 1707: 1588: 1369:A truth table makes it clear that 679: 231:{\displaystyle A\Leftrightarrow B} 162: 159: 133: 25: 3467: 2136:{\displaystyle a^{2}+b^{2}=c^{2}} 1994:{\displaystyle a^{2}+b^{2}=c^{2}} 657:{\displaystyle {\overline {A+B}}} 3425: 3242:{\displaystyle \leftrightarrow } 3031: 2695: 2335:The converse of the implication 2021:a triangle with sides of length 1853:a triangle with sides of length 1785: 1757: 1747:{\displaystyle \Leftrightarrow } 1727: 1649:{\displaystyle \Leftrightarrow } 1170: 1169: 738:{\displaystyle {\overline {A}}} 3283: 3236: 3112: 3083: 3058: 2950:A Modern Introduction to Logic 2891: 2875: 2858: 2838: 2828:& Thomas Ströhlein (1993) 2819: 2791: 2766: 2660: 2654: 2648: 2645: 2639: 2614:first-order predicate calculus 2429:. For example, going from "No 2361: 2301: 2289: 2283: 2271: 1741: 1643: 1618: 1461: 1443:{\displaystyle P\rightarrow Q} 1434: 1278: 1059: 1007: 613: 503:{\displaystyle A\not \equiv B} 401: 343:{\displaystyle A\rightarrow B} 334: 291:{\displaystyle A\Rightarrow B} 282: 248: 222: 171:{\displaystyle A\&\&B} 13: 1: 3318:{\displaystyle \nrightarrow } 2888:, C. Scribner's sons, p. 156. 2746: 2370:{\displaystyle P\leftarrow Q} 1838:will be "Given P, if R then Q 1627:{\displaystyle P\leftarrow Q} 1470:{\displaystyle P\leftarrow Q} 1287:{\displaystyle P\leftarrow Q} 1068:{\displaystyle A\leftarrow B} 1016:{\displaystyle A\Leftarrow B} 622:{\displaystyle A\downarrow B} 3343:{\displaystyle \nleftarrow } 3118:{\displaystyle \rightarrow } 1543:. However, if the statement 1337:). In general, the truth of 873:{\displaystyle A\parallel B} 730: 649: 585: 463: 373: 7: 3289:{\displaystyle \downarrow } 3089:{\displaystyle \leftarrow } 2688: 2330: 1305:be a statement of the form 410:{\displaystyle A\uparrow B} 10: 3472: 2578:propositions, neither is. 2418: 2396:{\displaystyle P\subset Q} 2377:, but may also be notated 1355:are logically equivalent. 1042:{\displaystyle A\subset B} 317:{\displaystyle A\supset B} 3422: 3385: 3265: 3160: 3064:{\displaystyle \uparrow } 3040: 3029: 2994: 2952:. Cromwell Company, 1931. 2759:Robert Audi, ed. (1999), 982:{\displaystyle A\oplus B} 205:{\displaystyle A\equiv B} 2897:Gordon Hunnings (1988), 1541:affirming the consequent 142:{\displaystyle A\&B} 93:{\displaystyle A\cdot B} 67:{\displaystyle A\land B} 3328:Converse nonimplication 1244:categorical proposition 1122:Functional completeness 847:{\displaystyle A\mid B} 795:{\displaystyle A\lor B} 436:{\displaystyle A\mid B} 3410: 3373: 3372:{\displaystyle \land } 3344: 3319: 3290: 3243: 3214: 3185: 3148: 3119: 3090: 3065: 3019: 2667: 2620:can be represented as 2455: 2397: 2371: 2317: 2239: 2200: 2183: 2174:Converse of a relation 2171: 2162: 2137: 2080: 2058: 2036: 2005: 1995: 1938: 1912: 1890: 1868: 1777: 1748: 1717: 1716:{\displaystyle \neg Q} 1693: 1672: 1650: 1628: 1598: 1597:{\displaystyle \neg Q} 1575: 1471: 1444: 1417: 1396: 1298: 1288: 1257:Implicational converse 1092:Propositional calculus 1069: 1043: 1017: 983: 957: 916: 874: 848: 822: 796: 762: 761:{\displaystyle \sim A} 739: 712: 689: 688:{\displaystyle \neg A} 658: 623: 597: 556: 530: 504: 472: 437: 411: 385: 344: 318: 292: 258: 232: 206: 172: 143: 117: 94: 68: 3432:Philosophy portal 3411: 3409:{\displaystyle \bot } 3374: 3345: 3320: 3291: 3244: 3215: 3186: 3184:{\displaystyle \neg } 3149: 3147:{\displaystyle \lor } 3120: 3091: 3066: 3020: 3018:{\displaystyle \top } 2933:Introduction to Logic 2886:The Elements of Logic 2741:Transposition (logic) 2681:cannot be swapped in 2668: 2451: 2398: 2372: 2318: 2240: 2201: 2181: 2163: 2138: 2081: 2059: 2037: 2016: 1996: 1939: 1913: 1891: 1869: 1848: 1807:Converse of a theorem 1778: 1776:{\displaystyle \lor } 1749: 1718: 1694: 1692:{\displaystyle \lor } 1673: 1651: 1629: 1599: 1576: 1472: 1445: 1418: 1397: 1289: 1264: 1150:Programming languages 1070: 1044: 1018: 984: 958: 917: 875: 849: 823: 797: 763: 740: 713: 690: 659: 624: 598: 557: 531: 505: 473: 438: 412: 386: 345: 319: 293: 259: 233: 207: 173: 144: 118: 95: 69: 3400: 3363: 3334: 3309: 3280: 3233: 3204: 3175: 3138: 3109: 3080: 3074:Converse implication 3055: 3009: 2830:Relations and Graphs 2624: 2484:(valid if P exists) 2437:to its converse "No 2415:Categorical converse 2381: 2355: 2252: 2214: 2190: 2152: 2094: 2070: 2048: 2026: 1952: 1928: 1902: 1880: 1858: 1767: 1738: 1704: 1683: 1662: 1640: 1612: 1585: 1565: 1455: 1428: 1407: 1386: 1373:and the converse of 1272: 1053: 1027: 1001: 967: 934: 892: 858: 832: 806: 780: 749: 722: 699: 676: 633: 607: 574: 540: 514: 488: 447: 421: 395: 362: 328: 302: 276: 242: 216: 190: 153: 127: 104: 78: 52: 3456:Immediate inference 3451:Logical connectives 2988:logical connectives 2935:. MacMillan, 1953. 2323:is also called the 1844:Pythagorean theorem 1842:. For example, the 1829:four-vertex theorem 1160:Philosophy of logic 821:{\displaystyle A+B} 34:Logical connectives 3406: 3369: 3340: 3315: 3286: 3239: 3210: 3181: 3144: 3115: 3086: 3061: 3045:Alternative denial 3015: 2866:Aristotelian Logic 2807:math.colostate.edu 2773:Taylor, Courtney. 2726:Logical connective 2663: 2445:. In the words of 2409:Bocheński notation 2393: 2367: 2313: 2235: 2196: 2184: 2169:is a right angle. 2158: 2133: 2076: 2054: 2032: 1991: 1945:is a right angle, 1934: 1908: 1886: 1864: 1846:can be stated as: 1773: 1744: 1713: 1689: 1668: 1646: 1624: 1594: 1571: 1467: 1440: 1413: 1392: 1299: 1284: 1249:, the converse is 1234:, the converse is 1155:Mathematical logic 1065: 1039: 1013: 979: 953: 948: 912: 870: 844: 818: 792: 758: 735: 711:{\displaystyle -A} 708: 685: 654: 619: 593: 552: 526: 500: 468: 433: 407: 381: 340: 314: 288: 254: 228: 202: 168: 139: 116:{\displaystyle AB} 113: 90: 64: 18:Conversion (logic) 3438: 3437: 2703:Philosophy portal 2556: 2555: 2247:converse relation 2199:{\displaystyle R} 2161:{\displaystyle c} 2079:{\displaystyle c} 2057:{\displaystyle b} 2035:{\displaystyle a} 1937:{\displaystyle c} 1911:{\displaystyle c} 1889:{\displaystyle b} 1867:{\displaystyle a} 1793: 1792: 1671:{\displaystyle P} 1574:{\displaystyle P} 1537: 1536: 1416:{\displaystyle Q} 1395:{\displaystyle P} 1325:is the statement 1297: 1209: 1208: 1078: 1077: 941: 908: 904: 900: 733: 652: 588: 466: 376: 16:(Redirected from 3463: 3430: 3429: 3428: 3415: 3413: 3412: 3407: 3378: 3376: 3375: 3370: 3349: 3347: 3346: 3341: 3324: 3322: 3321: 3316: 3295: 3293: 3292: 3287: 3248: 3246: 3245: 3240: 3219: 3217: 3216: 3211: 3190: 3188: 3187: 3182: 3153: 3151: 3150: 3145: 3124: 3122: 3121: 3116: 3095: 3093: 3092: 3087: 3070: 3068: 3067: 3062: 3035: 3024: 3022: 3021: 3016: 2980: 2973: 2966: 2957: 2956: 2906: 2895: 2889: 2879: 2873: 2862: 2856: 2842: 2836: 2823: 2817: 2816: 2814: 2813: 2804: 2795: 2789: 2788: 2786: 2785: 2770: 2764: 2757: 2705: 2700: 2699: 2698: 2672: 2670: 2669: 2664: 2518:Some P is not S 2468: 2467: 2402: 2400: 2399: 2394: 2376: 2374: 2373: 2368: 2322: 2320: 2319: 2314: 2264: 2263: 2244: 2242: 2241: 2236: 2205: 2203: 2202: 2197: 2167: 2165: 2164: 2159: 2142: 2140: 2139: 2134: 2132: 2131: 2119: 2118: 2106: 2105: 2085: 2083: 2082: 2077: 2063: 2061: 2060: 2055: 2041: 2039: 2038: 2033: 2000: 1998: 1997: 1992: 1990: 1989: 1977: 1976: 1964: 1963: 1943: 1941: 1940: 1935: 1917: 1915: 1914: 1909: 1895: 1893: 1892: 1887: 1873: 1871: 1870: 1865: 1789: 1782: 1780: 1779: 1774: 1761: 1753: 1751: 1750: 1745: 1731: 1722: 1720: 1719: 1714: 1698: 1696: 1695: 1690: 1677: 1675: 1674: 1669: 1655: 1653: 1652: 1647: 1633: 1631: 1630: 1625: 1606: 1605: 1603: 1601: 1600: 1595: 1580: 1578: 1577: 1572: 1476: 1474: 1473: 1468: 1449: 1447: 1446: 1441: 1422: 1420: 1419: 1414: 1401: 1399: 1398: 1393: 1380: 1379: 1295: 1293: 1291: 1290: 1285: 1201: 1194: 1187: 1173: 1172: 1117:Boolean function 1083:Related concepts 1074: 1072: 1071: 1066: 1048: 1046: 1045: 1040: 1022: 1020: 1019: 1014: 988: 986: 985: 980: 962: 960: 959: 954: 949: 921: 919: 918: 913: 906: 905: 902: 898: 879: 877: 876: 871: 853: 851: 850: 845: 827: 825: 824: 819: 801: 799: 798: 793: 767: 765: 764: 759: 744: 742: 741: 736: 734: 726: 717: 715: 714: 709: 694: 692: 691: 686: 663: 661: 660: 655: 653: 648: 637: 628: 626: 625: 620: 602: 600: 599: 594: 589: 581: 561: 559: 558: 553: 535: 533: 532: 527: 509: 507: 506: 501: 477: 475: 474: 469: 467: 462: 451: 442: 440: 439: 434: 416: 414: 413: 408: 390: 388: 387: 382: 377: 369: 349: 347: 346: 341: 323: 321: 320: 315: 297: 295: 294: 289: 263: 261: 260: 255: 237: 235: 234: 229: 211: 209: 208: 203: 177: 175: 174: 169: 148: 146: 145: 140: 122: 120: 119: 114: 99: 97: 96: 91: 73: 71: 70: 65: 41: 40: 30: 29: 21: 3471: 3470: 3466: 3465: 3464: 3462: 3461: 3460: 3441: 3440: 3439: 3434: 3426: 3424: 3418: 3401: 3398: 3397: 3381: 3364: 3361: 3360: 3335: 3332: 3331: 3310: 3307: 3306: 3281: 3278: 3277: 3261: 3234: 3231: 3230: 3205: 3202: 3201: 3176: 3173: 3172: 3156: 3139: 3136: 3135: 3110: 3107: 3106: 3081: 3078: 3077: 3056: 3053: 3052: 3036: 3027: 3010: 3007: 3006: 2990: 2984: 2946:Stebbing, Susan 2915: 2913:Further reading 2910: 2909: 2896: 2892: 2882:James H. Hyslop 2880: 2876: 2863: 2859: 2843: 2839: 2826:Gunther Schmidt 2824: 2820: 2811: 2809: 2802: 2796: 2792: 2783: 2781: 2771: 2767: 2758: 2754: 2749: 2721:Inverse (logic) 2701: 2696: 2694: 2691: 2625: 2622: 2621: 2544:Some S is not P 2477:Simple converse 2423: 2417: 2382: 2379: 2378: 2356: 2353: 2352: 2343:may be written 2333: 2259: 2255: 2253: 2250: 2249: 2215: 2212: 2211: 2208:binary relation 2191: 2188: 2187: 2176: 2153: 2150: 2149: 2127: 2123: 2114: 2110: 2101: 2097: 2095: 2092: 2091: 2071: 2068: 2067: 2049: 2046: 2045: 2027: 2024: 2023: 1985: 1981: 1972: 1968: 1959: 1955: 1953: 1950: 1949: 1929: 1926: 1925: 1903: 1900: 1899: 1881: 1878: 1877: 1859: 1856: 1855: 1809: 1768: 1765: 1764: 1754:   1739: 1736: 1735: 1705: 1702: 1701: 1684: 1681: 1680: 1663: 1660: 1659: 1656:   1641: 1638: 1637: 1613: 1610: 1609: 1586: 1583: 1582: 1566: 1563: 1562: 1456: 1453: 1452: 1429: 1426: 1425: 1408: 1405: 1404: 1387: 1384: 1383: 1294: 1273: 1270: 1269: 1259: 1205: 1164: 1131: 1102:Boolean algebra 1097:Predicate logic 1054: 1051: 1050: 1028: 1025: 1024: 1002: 999: 998: 968: 965: 964: 940: 935: 932: 931: 901: 893: 890: 889: 859: 856: 855: 833: 830: 829: 807: 804: 803: 781: 778: 777: 750: 747: 746: 725: 723: 720: 719: 700: 697: 696: 677: 674: 673: 638: 636: 634: 631: 630: 608: 605: 604: 580: 575: 572: 571: 541: 538: 537: 515: 512: 511: 489: 486: 485: 452: 450: 448: 445: 444: 422: 419: 418: 396: 393: 392: 368: 363: 360: 359: 329: 326: 325: 303: 300: 299: 277: 274: 273: 243: 240: 239: 217: 214: 213: 191: 188: 187: 154: 151: 150: 128: 125: 124: 105: 102: 101: 79: 76: 75: 53: 50: 49: 28: 23: 22: 15: 12: 11: 5: 3469: 3459: 3458: 3453: 3436: 3435: 3423: 3420: 3419: 3417: 3416: 3405: 3386: 3383: 3382: 3380: 3379: 3368: 3350: 3339: 3325: 3314: 3299:Nonimplication 3296: 3285: 3266: 3263: 3262: 3260: 3259: 3256:Digital buffer 3249: 3238: 3220: 3209: 3191: 3180: 3161: 3158: 3157: 3155: 3154: 3143: 3125: 3114: 3096: 3085: 3071: 3060: 3041: 3038: 3037: 3030: 3028: 3026: 3025: 3014: 2995: 2992: 2991: 2983: 2982: 2975: 2968: 2960: 2954: 2953: 2943: 2940:Symbolic Logic 2938:Copi, Irving. 2936: 2926: 2914: 2911: 2908: 2907: 2901:, SUNY Press, 2890: 2874: 2868:, SUNY Press, 2857: 2837: 2834:Springer books 2818: 2790: 2765: 2751: 2750: 2748: 2745: 2744: 2743: 2738: 2733: 2728: 2723: 2718: 2716:Contraposition 2713: 2707: 2706: 2690: 2687: 2662: 2659: 2656: 2653: 2650: 2647: 2644: 2641: 2638: 2635: 2632: 2629: 2554: 2553: 2550: 2545: 2542: 2536: 2535: 2532: 2529: 2526: 2520: 2519: 2516: 2513: 2510: 2504: 2503: 2500: 2495: 2492: 2486: 2485: 2478: 2475: 2472: 2465:propositions: 2416: 2413: 2392: 2389: 2386: 2366: 2363: 2360: 2332: 2329: 2312: 2309: 2306: 2303: 2300: 2297: 2294: 2291: 2288: 2285: 2282: 2279: 2276: 2273: 2270: 2267: 2262: 2258: 2234: 2231: 2228: 2225: 2222: 2219: 2195: 2175: 2172: 2157: 2130: 2126: 2122: 2117: 2113: 2109: 2104: 2100: 2075: 2053: 2031: 1988: 1984: 1980: 1975: 1971: 1967: 1962: 1958: 1933: 1907: 1885: 1863: 1808: 1805: 1791: 1790: 1783: 1772: 1762: 1755: 1743: 1734:   1732: 1724: 1723: 1712: 1709: 1699: 1688: 1678: 1667: 1657: 1645: 1636:   1634: 1623: 1620: 1617: 1593: 1590: 1570: 1553:if and only if 1535: 1534: 1531: 1528: 1525: 1521: 1520: 1517: 1514: 1511: 1507: 1506: 1503: 1500: 1497: 1493: 1492: 1489: 1486: 1483: 1479: 1478: 1466: 1463: 1460: 1450: 1439: 1436: 1433: 1423: 1412: 1402: 1391: 1283: 1280: 1277: 1258: 1255: 1207: 1206: 1204: 1203: 1196: 1189: 1181: 1178: 1177: 1166: 1165: 1163: 1162: 1157: 1152: 1147: 1141: 1138: 1137: 1133: 1132: 1130: 1129: 1124: 1119: 1114: 1112:Truth function 1109: 1104: 1099: 1094: 1088: 1085: 1084: 1080: 1079: 1076: 1075: 1064: 1061: 1058: 1038: 1035: 1032: 1012: 1009: 1006: 996: 990: 989: 978: 975: 972: 952: 947: 944: 939: 929: 923: 922: 911: 897: 887: 881: 880: 869: 866: 863: 843: 840: 837: 817: 814: 811: 791: 788: 785: 775: 769: 768: 757: 754: 732: 729: 707: 704: 684: 681: 671: 665: 664: 651: 647: 644: 641: 618: 615: 612: 592: 587: 584: 579: 569: 563: 562: 551: 548: 545: 525: 522: 519: 499: 496: 493: 483: 479: 478: 465: 461: 458: 455: 432: 429: 426: 406: 403: 400: 380: 375: 372: 367: 357: 351: 350: 339: 336: 333: 313: 310: 307: 287: 284: 281: 271: 265: 264: 253: 250: 247: 227: 224: 221: 201: 198: 195: 185: 179: 178: 167: 164: 161: 158: 138: 135: 132: 112: 109: 89: 86: 83: 63: 60: 57: 47: 37: 36: 26: 9: 6: 4: 3: 2: 3468: 3457: 3454: 3452: 3449: 3448: 3446: 3433: 3421: 3395: 3391: 3390:Contradiction 3388: 3387: 3384: 3366: 3358: 3354: 3351: 3337: 3329: 3326: 3312: 3304: 3300: 3297: 3275: 3271: 3268: 3267: 3264: 3257: 3253: 3250: 3228: 3224: 3223:Biconditional 3221: 3207: 3199: 3195: 3192: 3170: 3166: 3163: 3162: 3159: 3141: 3133: 3129: 3126: 3104: 3100: 3097: 3075: 3072: 3050: 3046: 3043: 3042: 3039: 3034: 3004: 3000: 2997: 2996: 2993: 2989: 2981: 2976: 2974: 2969: 2967: 2962: 2961: 2958: 2951: 2947: 2944: 2941: 2937: 2934: 2930: 2927: 2924: 2920: 2917: 2916: 2904: 2900: 2894: 2887: 2883: 2878: 2871: 2867: 2861: 2854: 2850: 2846: 2841: 2835: 2831: 2827: 2822: 2808: 2801: 2794: 2780: 2776: 2769: 2762: 2756: 2752: 2742: 2739: 2737: 2734: 2732: 2729: 2727: 2724: 2722: 2719: 2717: 2714: 2712: 2709: 2708: 2704: 2693: 2686: 2684: 2680: 2676: 2657: 2651: 2642: 2636: 2633: 2630: 2619: 2615: 2610: 2608: 2604: 2600: 2596: 2592: 2588: 2584: 2579: 2577: 2573: 2569: 2565: 2561: 2551: 2549: 2546: 2543: 2541: 2538: 2537: 2533: 2530: 2527: 2525: 2522: 2521: 2517: 2514: 2511: 2509: 2506: 2505: 2501: 2499: 2496: 2493: 2491: 2488: 2487: 2483: 2479: 2476: 2473: 2470: 2469: 2466: 2464: 2460: 2454: 2450: 2448: 2444: 2440: 2436: 2432: 2428: 2422: 2412: 2410: 2406: 2390: 2387: 2384: 2364: 2358: 2350: 2346: 2342: 2338: 2328: 2326: 2307: 2304: 2298: 2295: 2292: 2286: 2280: 2277: 2274: 2265: 2260: 2256: 2248: 2232: 2229: 2226: 2223: 2220: 2217: 2209: 2193: 2180: 2170: 2168: 2155: 2146: 2128: 2124: 2120: 2115: 2111: 2107: 2102: 2098: 2090: 2086: 2073: 2064: 2051: 2042: 2029: 2020: 2015: 2013: 2012: 2004: 2003: 1986: 1982: 1978: 1973: 1969: 1965: 1960: 1956: 1948: 1944: 1931: 1922: 1918: 1905: 1896: 1883: 1874: 1861: 1852: 1847: 1845: 1841: 1837: 1832: 1830: 1826: 1822: 1818: 1814: 1804: 1802: 1798: 1788: 1784: 1770: 1763: 1760: 1756: 1733: 1730: 1726: 1725: 1710: 1700: 1686: 1679: 1665: 1658: 1635: 1621: 1615: 1608: 1607: 1604: 1591: 1568: 1559: 1557: 1554: 1550: 1546: 1542: 1532: 1529: 1526: 1523: 1522: 1518: 1515: 1512: 1509: 1508: 1504: 1501: 1498: 1495: 1494: 1490: 1487: 1484: 1481: 1480: 1464: 1458: 1451: 1437: 1431: 1424: 1410: 1403: 1389: 1382: 1381: 1378: 1376: 1372: 1367: 1363: 1361: 1356: 1354: 1351: 1347: 1344: 1340: 1336: 1332: 1328: 1324: 1320: 1316: 1312: 1308: 1304: 1281: 1275: 1267: 1263: 1254: 1252: 1248: 1245: 1241: 1237: 1233: 1229: 1226: 1222: 1218: 1214: 1202: 1197: 1195: 1190: 1188: 1183: 1182: 1180: 1179: 1176: 1168: 1167: 1161: 1158: 1156: 1153: 1151: 1148: 1146: 1145:Digital logic 1143: 1142: 1140: 1139: 1135: 1134: 1128: 1127:Scope (logic) 1125: 1123: 1120: 1118: 1115: 1113: 1110: 1108: 1105: 1103: 1100: 1098: 1095: 1093: 1090: 1089: 1087: 1086: 1082: 1081: 1062: 1056: 1036: 1033: 1030: 1010: 1004: 997: 995: 992: 991: 976: 973: 970: 950: 945: 942: 937: 930: 928: 925: 924: 909: 895: 888: 886: 883: 882: 867: 864: 861: 841: 838: 835: 815: 812: 809: 789: 786: 783: 776: 774: 771: 770: 755: 752: 727: 705: 702: 682: 672: 670: 667: 666: 645: 642: 639: 616: 610: 590: 582: 577: 570: 568: 565: 564: 549: 546: 543: 523: 520: 517: 497: 494: 491: 484: 482:nonequivalent 481: 480: 459: 456: 453: 430: 427: 424: 404: 398: 378: 370: 365: 358: 356: 353: 352: 337: 331: 311: 308: 305: 285: 279: 272: 270: 267: 266: 251: 245: 225: 219: 199: 196: 193: 186: 184: 181: 180: 165: 156: 136: 130: 110: 107: 87: 84: 81: 61: 58: 55: 48: 46: 43: 42: 39: 38: 35: 32: 31: 19: 3270:Joint denial 3194:Exclusive or 3073: 2949: 2939: 2932: 2929:Copi, Irving 2922: 2898: 2893: 2885: 2877: 2865: 2860: 2848: 2840: 2829: 2821: 2810:. Retrieved 2806: 2793: 2782:. Retrieved 2778: 2768: 2760: 2755: 2682: 2678: 2674: 2617: 2611: 2607:per accidens 2606: 2599:per accidens 2598: 2595:per accidens 2594: 2590: 2586: 2582: 2580: 2575: 2574:, while for 2567: 2563: 2559: 2557: 2547: 2539: 2523: 2507: 2502:Some P is S 2497: 2489: 2482:per accidens 2481: 2462: 2458: 2456: 2452: 2442: 2438: 2434: 2430: 2426: 2424: 2404: 2348: 2344: 2340: 2336: 2334: 2324: 2185: 2148: 2144: 2088: 2066: 2044: 2022: 2018: 2017: 2010: 2006: 2001: 1946: 1924: 1920: 1898: 1876: 1854: 1850: 1849: 1839: 1835: 1833: 1824: 1820: 1816: 1812: 1810: 1800: 1796: 1794: 1560: 1555: 1548: 1544: 1538: 1374: 1370: 1368: 1364: 1357: 1352: 1345: 1338: 1334: 1330: 1326: 1322: 1318: 1317:). Then the 1314: 1310: 1306: 1302: 1300: 1266:Venn diagram 1250: 1246: 1239: 1235: 1231: 1227: 1220: 1210: 1136:Applications 993: 3353:Conjunction 3303:NIMPLY gate 3128:Disjunction 3099:Implication 2683:All S are P 2618:All S are P 2572:distributed 2531:Some P is S 2528:Some S is P 2494:All S are P 1327:Q implies P 1307:P implies Q 1251:All P are S 1247:All S are P 1225:implication 1217:mathematics 1107:Truth table 3445:Categories 3103:IMPLY gate 2832:, page 9, 2812:2019-11-26 2784:2019-11-27 2747:References 2736:Term logic 2603:syllogisms 2474:Convertend 2427:conversion 2419:See also: 1477:(converse) 1350:consequent 1343:antecedent 1242:. For the 183:equivalent 3404:⊥ 3367:∧ 3338:↚ 3313:↛ 3284:↓ 3252:Statement 3237:↔ 3227:XNOR gate 3179:¬ 3142:∨ 3113:→ 3084:← 3059:↑ 3049:NAND gate 3013:⊤ 2999:Tautology 2919:Aristotle 2845:Asa Mahan 2779:ThoughtCo 2731:Obversion 2711:Aristotle 2649:→ 2628:∀ 2548:not valid 2515:No P is S 2512:No S is P 2498:not valid 2480:Converse 2447:Asa Mahan 2388:⊂ 2362:← 2325:transpose 2305:∈ 2245:then the 2227:× 2221:⊆ 2009:Euclid's 1771:∨ 1742:⇔ 1708:¬ 1687:∨ 1644:⇔ 1619:← 1589:¬ 1462:← 1435:→ 1279:← 1060:← 1034:⊂ 1008:⇐ 974:⊕ 946:_ 943:∨ 865:∥ 839:∣ 787:∨ 753:∼ 731:¯ 703:− 680:¬ 650:¯ 614:↓ 586:¯ 583:∨ 547:↮ 464:¯ 457:⋅ 428:∣ 402:↑ 374:¯ 371:∧ 335:→ 309:⊃ 283:⇒ 249:⇋ 223:⇔ 197:≡ 163:& 160:& 134:& 85:⋅ 59:∧ 3357:AND gate 3274:NOR gate 3208:↮ 3198:XOR gate 3169:NOT gate 3165:Negation 2884:(1892), 2689:See also 2331:Notation 2011:Elements 1819:will be 1799:without 1551:is true 1348:and the 1319:converse 1221:converse 1175:Category 994:converse 521:⇎ 495:≢ 3359:)  3355: ( 3305:)  3301: ( 3276:)  3272: ( 3254: ( 3229:)  3225: ( 3200:)  3196: ( 3171:)  3167: ( 3134:)  3132:OR gate 3130: ( 3105:)  3101: ( 3051:)  3047: ( 2986:Common 2923:Organon 2847:(1857) 2403:, or "B 269:implies 3396:  3330:  3076:  3005:  2870:p. 207 2407:" (in 2065:, and 1897:, and 1219:, the 907:  899:  3394:False 2903:p. 42 2853:p. 82 2803:(PDF) 2210:with 2206:is a 2019:Given 1851:Given 1213:logic 3003:True 2677:and 2581:For 2562:and 2471:Type 2461:and 2441:are 2433:are 2145:then 1947:then 1581:and 1360:true 1301:Let 1215:and 903:XNOR 885:XNOR 355:NAND 2612:In 2411:). 2186:If 1803:". 1321:of 1268:of 1211:In 927:XOR 669:NOT 567:NOR 45:AND 3447:: 2948:. 2931:. 2921:. 2851:, 2805:. 2777:. 2685:. 2616:, 2552:– 2534:– 2449:: 2443:S" 2435:P" 2405:pq 2351:, 2347:→ 2339:→ 2327:. 2143:, 2089:if 2087:, 2043:, 1921:if 1919:, 1875:, 1823:→ 1815:→ 1362:. 1333:→ 1313:→ 1238:→ 1230:→ 1049:, 1023:, 963:, 854:, 828:, 802:, 773:OR 745:, 718:, 695:, 629:, 603:, 536:, 510:, 443:, 417:, 391:, 324:, 298:, 238:, 212:, 149:, 123:, 100:, 74:, 3392:/ 3258:) 3001:/ 2979:e 2972:t 2965:v 2925:. 2905:. 2872:. 2855:. 2815:. 2787:. 2679:P 2675:S 2661:) 2658:x 2655:( 2652:P 2646:) 2643:x 2640:( 2637:S 2634:. 2631:x 2591:A 2587:A 2583:A 2576:I 2568:E 2564:I 2560:E 2540:O 2524:I 2508:E 2490:A 2463:I 2459:E 2439:P 2431:S 2391:Q 2385:P 2365:Q 2359:P 2349:P 2345:Q 2341:Q 2337:P 2311:} 2308:R 2302:) 2299:b 2296:, 2293:a 2290:( 2287:: 2284:) 2281:a 2278:, 2275:b 2272:( 2269:{ 2266:= 2261:T 2257:R 2233:, 2230:B 2224:A 2218:R 2194:R 2156:c 2129:2 2125:c 2121:= 2116:2 2112:b 2108:+ 2103:2 2099:a 2074:c 2052:b 2030:a 2002:. 1987:2 1983:c 1979:= 1974:2 1970:b 1966:+ 1961:2 1957:a 1932:c 1906:c 1884:b 1862:a 1840:" 1836:" 1825:P 1821:Q 1817:Q 1813:P 1801:P 1797:Q 1711:Q 1666:P 1622:Q 1616:P 1592:Q 1569:P 1556:Q 1549:P 1545:S 1533:T 1530:T 1527:T 1524:T 1519:T 1516:F 1513:F 1510:T 1505:F 1502:T 1499:T 1496:F 1491:T 1488:T 1485:F 1482:F 1465:Q 1459:P 1438:Q 1432:P 1411:Q 1390:P 1375:S 1371:S 1353:Q 1346:P 1339:S 1335:P 1331:Q 1329:( 1323:S 1315:Q 1311:P 1309:( 1303:S 1282:Q 1276:P 1240:P 1236:Q 1232:Q 1228:P 1200:e 1193:t 1186:v 1063:B 1057:A 1037:B 1031:A 1011:B 1005:A 977:B 971:A 951:B 938:A 910:B 896:A 868:B 862:A 842:B 836:A 816:B 813:+ 810:A 790:B 784:A 756:A 728:A 706:A 683:A 646:B 643:+ 640:A 617:B 611:A 591:B 578:A 550:B 544:A 524:B 518:A 498:B 492:A 460:B 454:A 431:B 425:A 405:B 399:A 379:B 366:A 338:B 332:A 312:B 306:A 286:B 280:A 252:B 246:A 226:B 220:A 200:B 194:A 166:B 157:A 137:B 131:A 111:B 108:A 88:B 82:A 62:B 56:A 20:)

Index

Conversion (logic)
Logical connectives
AND
equivalent
implies
NAND
NOR
NOT
OR
XNOR
XOR
converse
Propositional calculus
Predicate logic
Boolean algebra
Truth table
Truth function
Boolean function
Functional completeness
Scope (logic)
Digital logic
Programming languages
Mathematical logic
Philosophy of logic
Category
v
t
e
logic
mathematics

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