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Drinker paradox

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for logics that demand relevant relationships between premise and consequent, unlike classical logic assumed here). The formal statement of the theorem is timeless, eliminating the second objection because the person the statement holds true for at one instant is not necessarily the same person it
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So as it was applied here, the statement "if they are drinking, everyone is drinking" was taken to be correct in one case, if everyone was drinking, and in the other case, if they were not drinking—even though their drinking may not have had anything to do with anyone else's drinking.
337:"there is a woman on earth such that if she becomes sterile, the whole human race will die out." Smullyan writes that this formulation emerged from a conversation he had with philosopher John Bacon. 650:. In Proceedings of the 14th International Conference on Theorem Proving in Higher Order Logics (TPHOLs '01), Richard J. Boulton and Paul B. Jackson (Eds.). Springer-Verlag, London, UK, 378-394. 333:
Smullyan in his 1978 book attributes the naming of "The Drinking Principle" to his graduate students. He also discusses variants (obtained by replacing D with other, more dramatic predicates):
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The proof begins by recognizing it is true that either everyone in the pub is drinking, or at least one person in the pub is not drinking. Consequently, there are two cases to consider:
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for the validity of the theorem. And if someone does not drink, then that particular non-drinking individual can be the witness to the theorem's validity.
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that can be stated as "There is someone in the pub such that, if he or she is drinking, then everyone in the pub is drinking." It was popularised by the
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If and only if there is someone in the pub, there is someone in the pub such that, if they are drinking, then everyone in the pub is drinking
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in formal logic, which states that "If P, then Q" is always true if P is false. (These kinds of statements are said to be
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the others to drink, or that there could be a person such that all through the night that one person were always the
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A slightly more formal way of expressing the above is to say that, if everybody drinks, then anyone can be the
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A "dual" version of the Principle: "there is at least one person such that if anybody drinks, then he does."
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What is important to the paradox is that the conditional in classical (and intuitionistic) logic is the
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In the setting with empty domains allowed, the drinker paradox must be formulated as follows:
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Otherwise at least one person is not drinking. For any nondrinking person, the statement
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Suppose everyone is drinking. For any particular person, it cannot be wrong to say that
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The paradox is ultimately based on the principle of formal logic that the statement
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As "Smullyan's ‘Drinkers’ principle" or just "Drinkers' principle" it appears in
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is true whenever A is false, i.e., any statement follows from a false statement (
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What is the Name of this Book? The Riddle of Dracula and Other Logical Puzzles
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if that particular person is drinking, then everyone in the pub is drinking
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if that particular person is drinking, then everyone in the pub is drinking
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nature of the statement comes from the way it is usually stated in
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H.P. Barendregt (1996). "The quest for correctness".
376: 289: 250: 100: 1226: 1055: 855: 734: 75:to drink. The first objection comes from confusing 582:. Stichting Mathematisch Centrum. pp. 54–55. 534: 449: 301: 262: 170: 711: 8: 1379: 718: 704: 696: 525: 523: 521: 519: 517: 515: 513: 511: 446: 375: 288: 249: 167: 99: 321:, this is also a sufficient condition). 507: 209:drinks, everybody includes that person. 91:The formal statement of the theorem is 681: 670: 317:is false (in classical logic, but not 88:holds true for at any other instant. 7: 185:and P is an arbitrary nonempty set. 81:Correlation does not imply causation 450:{\displaystyle \exists x\in P.\ \,} 1036:What the Tortoise Said to Achilles 667:. Computability in Europe 2010: 2. 413: 377: 171:{\displaystyle \exists x\in P,.\,} 134: 101: 14: 1389: 1388: 1378: 460:if and only if it is non-empty. 79:statements with causation (see 443: 440: 434: 410: 407: 401: 395: 302:{\displaystyle A\rightarrow B} 293: 263:{\displaystyle A\rightarrow B} 254: 161: 158: 152: 131: 128: 122: 116: 55:What Is the Name of this Book? 1: 660:MartĂ­n EscardĂł; Paulo Oliva. 240:Explanation of paradoxicality 576:Images of SMC Research 1996 283:. It has the property that 1436: 623:Sets, Logic and Categories 1374: 648:Mizar Light for HOL Light 486:Reification (linguistics) 626:. Springer. p. 91. 181:where D is an arbitrary 16:Apparent logical paradox 955:Paradoxes of set theory 680:Cite journal requires 451: 329:History and variations 303: 264: 216:is formally true: its 172: 646:Freek Wiedijk. 2001. 452: 304: 265: 173: 48:mathematical logician 1321:Kavka's toxin puzzle 1093:Income and fertility 374: 319:intuitionistic logic 287: 281:material conditional 248: 222:material implication 98: 980:Temperature paradox 903:Free choice paradox 767:Fitch's knowability 350:automated reasoning 29:drinker's principle 23:(also known as the 1356:Prisoner's dilemma 1042:Heat death paradox 1030:Unexpected hanging 995:Chicken or the egg 447: 367:A set P satisfies 299: 273:ex falso quodlibet 260: 168: 33:drinking principle 1420:Logical paradoxes 1402: 1401: 1073:Arrow information 633:978-1-85233-056-9 589:978-90-6196-462-9 481:List of paradoxes 430: 394: 25:drinker's theorem 1427: 1392: 1391: 1382: 1381: 1193:Service recovery 1047:Olbers's paradox 747:Buridan's bridge 720: 713: 706: 697: 690: 689: 683: 678: 676: 668: 666: 657: 651: 644: 638: 637: 618:Peter J. Cameron 614: 608: 607: 605: 604: 598: 592:. Archived from 581: 570: 557: 556: 540: 531:Raymond Smullyan 527: 456: 454: 453: 448: 428: 392: 360:Non-empty domain 354:proof assistants 309:is true only if 308: 306: 305: 300: 269: 267: 266: 261: 177: 175: 174: 169: 77:formal "if then" 65:natural language 51:Raymond Smullyan 1435: 1434: 1430: 1429: 1428: 1426: 1425: 1424: 1415:Predicate logic 1405: 1404: 1403: 1398: 1370: 1281:Decision-making 1227:Decision theory 1222: 1051: 975:Hilbert's Hotel 908:Grelling–Nelson 851: 730: 724: 694: 693: 679: 669: 664: 659: 658: 654: 645: 641: 634: 616: 615: 611: 602: 600: 596: 590: 579: 572: 571: 560: 553: 529: 528: 509: 504: 496:Relevance logic 477: 372: 371: 362: 346:H.P. Barendregt 331: 285: 284: 246: 245: 242: 191: 96: 95: 85:Relevance logic 59:The apparently 44:predicate logic 21:drinker paradox 17: 12: 11: 5: 1433: 1431: 1423: 1422: 1417: 1407: 1406: 1400: 1399: 1397: 1396: 1386: 1375: 1372: 1371: 1369: 1368: 1363: 1358: 1353: 1348: 1343: 1338: 1333: 1328: 1323: 1318: 1313: 1308: 1303: 1298: 1293: 1288: 1283: 1278: 1273: 1268: 1263: 1258: 1257: 1256: 1251: 1246: 1236: 1230: 1228: 1224: 1223: 1221: 1220: 1215: 1210: 1205: 1200: 1198:St. Petersburg 1195: 1190: 1185: 1180: 1175: 1170: 1165: 1160: 1155: 1150: 1145: 1140: 1135: 1130: 1125: 1120: 1115: 1110: 1105: 1100: 1095: 1090: 1085: 1080: 1075: 1070: 1065: 1059: 1057: 1053: 1052: 1050: 1049: 1044: 1039: 1032: 1027: 1022: 1017: 1012: 1007: 1002: 997: 992: 987: 982: 977: 972: 967: 962: 957: 952: 947: 946: 945: 940: 935: 930: 925: 915: 910: 905: 900: 895: 890: 885: 880: 875: 870: 865: 859: 857: 853: 852: 850: 849: 844: 839: 834: 829: 827:Rule-following 824: 819: 814: 809: 804: 799: 794: 789: 784: 779: 774: 769: 764: 759: 754: 752:Dream argument 749: 744: 738: 736: 732: 731: 725: 723: 722: 715: 708: 700: 692: 691: 682:|journal= 652: 639: 632: 609: 588: 558: 551: 506: 505: 503: 500: 499: 498: 493: 491:Temporal logic 488: 483: 476: 473: 472: 471: 458: 457: 445: 442: 439: 436: 433: 427: 424: 421: 418: 415: 412: 409: 406: 403: 400: 397: 391: 388: 385: 382: 379: 361: 358: 342: 341: 338: 330: 327: 313:is true or if 298: 295: 292: 259: 256: 253: 241: 238: 230: 229: 226:vacuously true 210: 190: 187: 179: 178: 166: 163: 160: 157: 154: 151: 148: 145: 142: 139: 136: 133: 130: 127: 124: 121: 118: 115: 112: 109: 106: 103: 15: 13: 10: 9: 6: 4: 3: 2: 1432: 1421: 1418: 1416: 1413: 1412: 1410: 1395: 1387: 1385: 1377: 1376: 1373: 1367: 1364: 1362: 1359: 1357: 1354: 1352: 1349: 1347: 1344: 1342: 1339: 1337: 1334: 1332: 1329: 1327: 1326:Morton's fork 1324: 1322: 1319: 1317: 1314: 1312: 1309: 1307: 1304: 1302: 1299: 1297: 1294: 1292: 1289: 1287: 1284: 1282: 1279: 1277: 1274: 1272: 1269: 1267: 1266:Buridan's ass 1264: 1262: 1259: 1255: 1252: 1250: 1247: 1245: 1242: 1241: 1240: 1239:Apportionment 1237: 1235: 1232: 1231: 1229: 1225: 1219: 1216: 1214: 1211: 1209: 1206: 1204: 1201: 1199: 1196: 1194: 1191: 1189: 1186: 1184: 1181: 1179: 1176: 1174: 1171: 1169: 1166: 1164: 1161: 1159: 1156: 1154: 1151: 1149: 1146: 1144: 1141: 1139: 1136: 1134: 1131: 1129: 1126: 1124: 1121: 1119: 1116: 1114: 1111: 1109: 1106: 1104: 1101: 1099: 1098:Downs–Thomson 1096: 1094: 1091: 1089: 1086: 1084: 1081: 1079: 1076: 1074: 1071: 1069: 1066: 1064: 1061: 1060: 1058: 1054: 1048: 1045: 1043: 1040: 1037: 1033: 1031: 1028: 1026: 1023: 1021: 1018: 1016: 1015:Plato's beard 1013: 1011: 1008: 1006: 1003: 1001: 998: 996: 993: 991: 988: 986: 983: 981: 978: 976: 973: 971: 968: 966: 963: 961: 958: 956: 953: 951: 948: 944: 941: 939: 936: 934: 931: 929: 926: 924: 921: 920: 919: 916: 914: 913:Kleene–Rosser 911: 909: 906: 904: 901: 899: 896: 894: 891: 889: 886: 884: 881: 879: 876: 874: 871: 869: 866: 864: 861: 860: 858: 854: 848: 845: 843: 840: 838: 837:Theseus' ship 835: 833: 830: 828: 825: 823: 820: 818: 815: 813: 810: 808: 805: 803: 800: 798: 797:Mere addition 795: 793: 790: 788: 785: 783: 780: 778: 775: 773: 770: 768: 765: 763: 760: 758: 755: 753: 750: 748: 745: 743: 740: 739: 737: 735:Philosophical 733: 729: 721: 716: 714: 709: 707: 702: 701: 698: 687: 674: 663: 656: 653: 649: 643: 640: 635: 629: 625: 624: 619: 613: 610: 599:on 2015-07-11 595: 591: 585: 578: 577: 569: 567: 565: 563: 559: 554: 552:0-13-955088-7 548: 544: 543:Prentice Hall 539: 538: 532: 526: 524: 522: 520: 518: 516: 514: 512: 508: 501: 497: 494: 492: 489: 487: 484: 482: 479: 478: 474: 469: 466: 465: 464: 463:Or in words: 461: 437: 431: 425: 422: 419: 416: 404: 398: 389: 386: 383: 380: 370: 369: 368: 365: 359: 357: 355: 351: 347: 339: 336: 335: 334: 328: 326: 322: 320: 316: 312: 296: 290: 282: 277: 275: 274: 257: 251: 239: 237: 235: 227: 223: 219: 215: 211: 208: 204: 200: 196: 195: 194: 188: 186: 184: 164: 155: 149: 146: 143: 140: 137: 125: 119: 113: 110: 107: 104: 94: 93: 92: 89: 86: 82: 78: 74: 70: 66: 62: 57: 56: 52: 49: 45: 42: 38: 34: 30: 26: 22: 1346:Preparedness 1178:Productivity 1158:Mandeville's 999: 950:Opposite Day 878:Burali-Forti 873:Bhartrhari's 673:cite journal 655: 642: 622: 612: 601:. 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Index

theorem
classical
predicate logic
mathematical logician
Raymond Smullyan
paradoxical
natural language
formal "if then"
Correlation does not imply causation
Relevance logic
predicate
antecedent
material implication
vacuously true
witness
ex falso quodlibet
material conditional
intuitionistic logic
H.P. Barendregt
automated reasoning
proof assistants
List of paradoxes
Reification (linguistics)
Temporal logic
Relevance logic




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