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Cantor's theorem

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9632: 27: 7284: 4647: 2536: 4446: 2387: 4642:{\displaystyle \mathbb {N} {\begin{Bmatrix}1&\longleftrightarrow &\{4,5\}\\2&\longleftrightarrow &\{1,2,3\}\\3&\longleftrightarrow &\{4,5,6\}\\4&\longleftrightarrow &\{1,3,5\}\\\vdots &\vdots &\vdots \end{Bmatrix}}{\mathcal {P}}(\mathbb {N} ).} 4127: 314:. For instance, by iteratively taking the power set of an infinite set and applying Cantor's theorem, we obtain an endless hierarchy of infinite cardinals, each strictly larger than the one before it. Consequently, the theorem implies that there is no largest 2531:{\displaystyle {\begin{aligned}\xi \in B&\iff \xi \notin f(\xi )&&{\text{(by definition of }}B{\text{)}};\\\xi \in B&\iff \xi \in f(\xi )&&{\text{(by assumption that }}f(\xi )=B{\text{)}}.\\\end{aligned}}} 6228:
has a theorem (which he calls "Cantor's Theorem") that is identical to the form above in the paper that became the foundation of modern set theory ("Untersuchungen ĂŒber die Grundlagen der Mengenlehre I"), published in 1908. See
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that contain the very same number. For instance, in our example the number 2 is paired with the subset {1, 2, 3}, which contains 2 as a member. Let us call such numbers
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that do not contain them. For instance, in our example the number 1 is paired with the subset {4, 5}, which does not contain the number 1. Call these numbers
3207:. For a countable (or finite) set, the argument of the proof given above can be illustrated by constructing a table in which each row is labelled by a unique 6126:). The version of this argument he gave in that paper was phrased in terms of indicator functions on a set rather than subsets of a set. He showed that if 2798: 1144: 461: 9671: 8011: 5529:. In order to distinguish this paradox from the next one discussed below, it is important to note what this contradiction is. By Cantor's theorem 8686: 7748: 5506:
is the name given to a contradiction following from Cantor's theorem together with the assumption that there is a set containing all sets, the
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emphasized that Russell's paradox is independent of considerations of cardinality and its underlying notions like one-to-one correspondence.
8769: 7910: 1211: 310:, who first stated and proved it at the end of the 19th century. Cantor's theorem had immediate and important consequences for the 6114:
Cantor gave essentially this proof in a paper published in 1891 "Über eine elementare Frage der Mannigfaltigkeitslehre", where the
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Cantor's argument is elegant and remarkably simple. The complete proof is presented below, with detailed explanations to follow.
4191: 4122:{\displaystyle {\mathcal {P}}(\mathbb {N} )=\{\varnothing ,\{1,2\},\{1,2,3\},\{4\},\{1,5\},\{3,4,6\},\{2,4,6,\dots \},\dots \}.} 6739: 6123: 287:
Much more significant is Cantor's discovery of an argument that is applicable to any set, and shows that the theorem holds for
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than objects. "For suppose a correlation of all objects and some propositional functions to have been affected, and let phi-
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constructed in the previous paragraphs coincides with the row labels for the subset of entries on this main diagonal
8579: 6734: 9334: 9078: 7903: 6241: 551: 5430: 5391: 5330: 5269: 5230: 5162: 5127: 5124:. Then, every number maps to a nonempty set and no number maps to the empty set. But the empty set is a member of 5029: 4705: 4408: 4351: 4290: 4134: 3912: 3877: 8639: 8332: 7743: 7337: 5664: 8073: 7623: 7192: 5532: 3740:
could, albeit with a certain amount of direction in terms of tactics that might perhaps be considered cheating.
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to show that these infinite sets are equinumerous. In other words, we will attempt to pair off each element of
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Despite the syntactical similarities between the Russell set (in either variant) and the Cantor diagonal set,
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The proof of Cantor's theorem is straightforwardly adapted to show that assuming a set of all sets
3725: 6863: 5469: 5369: 5308: 5208: 5007: 4386: 4329: 4267: 4169: 3848: 2235: 2151: 1971: 1742: 1471:) can reach every possible subset, i.e., we just need to demonstrate the existence of a subset of 653: 9285: 9262: 9223: 9109: 9050: 8696: 8616: 8460: 8404: 8017: 7862: 7780: 7655: 7607: 7421: 7344: 7155: 7092: 6985: 5497: 5363: 899: 64: 58: 5723:
Another paradox can be derived from the proof of Cantor's theorem by instantiating the function
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to produce it. The main difficulty lies in an automated discovery of the Cantor diagonal set.
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Using this idea, let us build a special set of natural numbers. This set will provide the
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does not agree with any column in at least one entry. Consequently, no column represents
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so that such table can be constructed. Each column of the table is labelled by a unique
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is selfish because it is in the corresponding set, which contradicts the definition of
4840: 4820: 4800: 4780: 4760: 4740: 4678: 3773: 3755: 3704: 3684: 3681:(swap "true" and "false") entries of the main diagonal. Thus the indicator function of 3660: 3654: 3601: 3581: 3500: 3454: 3434: 3356: 3336: 3312: 3288: 3210: 3151: 3128: 3108: 3088: 3068: 3048: 3028: 3008: 2988: 2968: 2948: 2928: 2904: 2884: 2864: 2778: 2732: 2712: 2689: 2669: 2649: 2629: 2609: 2296: 2215: 2070: 1890: 1866: 1846: 1797: 1777: 1602: 1578: 1474: 1454: 1434: 1414: 1394: 1373: 1352: 1330: 1309: 1303: 1299: 1281: 1261: 1003: 997: 973: 769: 681: 524: 359: 339: 203: 168: 90: 8589: 1391:. This is the heart of Cantor's theorem: there is no surjective function from any set 9631: 9571: 9378: 9188: 9178: 9070: 8951: 8786: 8762: 8543: 8527: 8432: 8409: 8286: 8255: 8220: 8115: 7950: 7579: 7416: 7379: 7349: 7273: 7060: 7021: 7002: 6994: 6962: 6955: 6891: 6888:
Proceedings of the Tarski Symposium. Proceedings of Symposia in Pure Mathematics XXV,
6867: 6831: 6780: 5728: 85: 7063: 6943:", p.276. Bulletin of Symbolic Logic vol. 9, no. 3, (2003). Accessed 21 August 2023. 2851:{\displaystyle \operatorname {card} (A)<\operatorname {card} ({\mathcal {P}}(A))} 2316:
Equivalently, and slightly more formally, we have just proved that the existence of
1197:{\displaystyle \operatorname {card} (A)<\operatorname {card} ({\mathcal {P}}(A))} 514:{\displaystyle \operatorname {card} (A)<\operatorname {card} ({\mathcal {P}}(A))} 9585: 9580: 9473: 9430: 9252: 9213: 9208: 9193: 9019: 8976: 8873: 8671: 8621: 8195: 8157: 7867: 7857: 7842: 7837: 7705: 7359: 7145: 6165: 3729: 3678: 42:}, is three, while there are eight elements in its power set (3 < 2 = 8), here 9566: 9556: 9510: 9493: 9448: 9410: 9312: 9232: 9039: 8966: 8939: 8927: 8833: 8747: 8721: 8676: 8644: 8445: 8247: 8190: 8140: 8105: 8063: 7736: 7674: 7492: 7305: 7112: 6990: 315: 26: 7077: 6928:
Georg Cantor, Gesammelte Abhandlungen mathematischen und philosophischen Inhalts
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ed. L. Henkin, Providence RI, Second printing with additions 1979, pp. 297−308.
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Finally, to complete the proof, we need to exhibit an injective function from
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to its power set. To establish this, it is enough to show that no function
307: 288: 43: 7020:, Springer Monographs in Mathematics (3rd millennium ed.), Springer, 3497:. Given the order chosen for the row and column labels, the main diagonal 9535: 9415: 8594: 8584: 8531: 8215: 8135: 8120: 8000: 7945: 7852: 7487: 7197: 7140: 7013: 6980: 6119: 5463: 5424: 5302: 5263: 5202: 3724:
Despite the simplicity of the above proof, it is rather difficult for an
3306: 292: 193: 162: 6031:{\displaystyle R_{U}\in R_{U}\iff (R_{U}\in U\wedge R_{U}\notin R_{U}).} 8465: 8320: 8291: 8097: 7832: 7603: 7259: 6940: 455: 189: 77: 9617: 9520: 8573: 8490: 8450: 8414: 8350: 8162: 8152: 8125: 7888: 7635: 7598: 7549: 7447: 7172: 7108: 7068: 6952: 5731:; this turns Cantor's diagonal set into what is sometimes called the 5001: 4700: 4262: 3872: 3330: 197: 135: 1251:{\displaystyle \operatorname {card} (X)<\operatorname {card} (Y)} 9602: 9400: 8848: 8553: 8147: 6396:
that does not have any fixed points; that is, there is no morphism
7001:(Springer-Verlag edition). Reprinted by Martino Fine Books, 2011. 4737:
contains all sets of natural numbers, and so it contains this set
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of the set corresponding to the column. The indicator function of
9198: 7990: 5906: 5000:, we have contradicted our original supposition, that there is a 296: 5423:. Therefore, only one possibility remains, and that is that the 2729:
to its power set. Finding such a function is trivial: just map
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provides for a broad generalization of Cantor's theorem to any
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earlier proved the uncountability of the reals by other methods
4661: 4653: 299:, is strictly larger than the cardinality of the integers; see 108: 6049:'s system for instance) by defining the Russell set simply as 4917:, then it is non-selfish and it should instead be a member of 3085:, another contradiction. So the assumption that an element of 8742: 8088: 7933: 7532: 7292: 7228: 7058: 6989:. Princeton, NJ: D. Van Nostrand Company, 1960. Reprinted by 6046: 3005:
because that would contradict the criterion of membership in
5801:{\displaystyle R_{A}=\left\{\,x\in A:x\not \in x\,\right\}.} 4652:
Given such a pairing, some natural numbers are paired with
6957:
Conceptual Mathematics: A First Introduction to Categories
6812:. University of Cambridge Computer Laboratory. p. 14. 5496:
Cantor's theorem and its proof are closely related to two
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Since there is no natural number which can be paired with
4254:{\displaystyle \{2,4,6,\ldots \}=\{2k:k\in \mathbb {N} \}} 3065:
meaning that it satisfies the criterion for membership in
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The previous deduction yields a contradiction of the form
5927: 6914:"Über eine elementare Frage der Mannigfaltigskeitslehre" 6174:(1903, section 348), where he shows that there are more 5084:
may be empty. This would mean that every natural number
6853: 6222:." He attributes the idea behind the proof to Cantor. 5366:, by definition, and these singletons form a "copy" of 4460: 926:{\displaystyle \varphi \Leftrightarrow \lnot \varphi } 6705: 6658: 6632: 6594: 6574: 6548: 6510: 6486: 6466: 6434: 6402: 6370: 6346: 6326: 6302: 6282: 6258: 6055: 5948: 5891:{\displaystyle R_{U}\in R_{U}\iff R_{U}\notin R_{U}.} 5833: 5748: 5667: 5647: 5614: 5594: 5535: 5515: 5472: 5433: 5394: 5372: 5333: 5311: 5272: 5233: 5211: 5165: 5130: 5110: 5090: 5070: 5032: 5010: 4986: 4963: 4943: 4923: 4903: 4883: 4863: 4843: 4823: 4803: 4783: 4763: 4743: 4708: 4681: 4449: 4411: 4389: 4354: 4332: 4293: 4270: 4194: 4172: 4137: 3953: 3915: 3880: 3851: 3786: 3758: 3707: 3687: 3663: 3624: 3604: 3584: 3558: 3523: 3503: 3477: 3457: 3437: 3379: 3359: 3339: 3315: 3291: 3233: 3213: 3174: 3154: 3131: 3111: 3091: 3071: 3051: 3031: 3011: 2991: 2971: 2951: 2931: 2907: 2887: 2867: 2801: 2781: 2755: 2735: 2715: 2692: 2672: 2652: 2632: 2612: 2577: 2551: 2390: 2348: 2322: 2299: 2273: 2238: 2218: 2189: 2154: 2128: 2093: 2073: 2044: 2009: 1974: 1939: 1913: 1893: 1869: 1849: 1820: 1800: 1780: 1745: 1719: 1693: 1628: 1605: 1581: 1552: 1526: 1497: 1477: 1457: 1437: 1417: 1397: 1376: 1355: 1349:
It suffices to show that there is no surjection from
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sets also. As a consequence, the cardinality of the
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Jahresbericht der Deutschen Mathematiker-Vereinigung
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Let us examine the proof for the specific case when
2881:, empty or non-empty, is always in the power set of 2666:
does not map onto every element of the power set of
295:, which is the same as that of the power set of the 192:, Cantor's theorem can be seen to be true by simple 6773:
Set Theory: With an Introduction to Real Point Sets
3431:, ..., in this order. The intersection of each row 2965:. But that leads to a contradiction: no element of 84:is a fundamental result which states that, for any 6954: 6946: 6941:The Empty Set, the Singleton, and the Ordered Pair 6886:Church, A. "Set theory with a universal set." in 6862:. Springer Science & Business Media. pp.  6717: 6691: 6644: 6618: 6580: 6560: 6534: 6496: 6472: 6452: 6420: 6388: 6356: 6332: 6312: 6288: 6268: 6092:{\displaystyle R=\left\{\,x:x\not \in x\,\right\}} 6091: 6030: 5890: 5800: 5712: 5653: 5633: 5600: 5580: 5521: 5480: 5454: 5415: 5380: 5354: 5319: 5293: 5254: 5219: 5186: 5151: 5116: 5104:maps to a subset of natural numbers that contains 5096: 5076: 5053: 5018: 4992: 4969: 4949: 4929: 4909: 4889: 4869: 4849: 4829: 4809: 4789: 4769: 4749: 4729: 4687: 4641: 4432: 4397: 4375: 4340: 4314: 4276: 4253: 4180: 4158: 4121: 3936: 3901: 3859: 3830: 3764: 3713: 3693: 3669: 3645: 3610: 3590: 3570: 3544: 3509: 3489: 3463: 3443: 3423: 3365: 3345: 3321: 3297: 3277: 3219: 3195: 3160: 3137: 3117: 3097: 3077: 3057: 3037: 3017: 2997: 2977: 2957: 2937: 2913: 2893: 2873: 2850: 2787: 2767: 2741: 2721: 2698: 2678: 2658: 2638: 2618: 2598: 2563: 2530: 2369: 2334: 2305: 2285: 2259: 2224: 2204: 2175: 2140: 2114: 2079: 2059: 2030: 1995: 1960: 1925: 1899: 1875: 1855: 1835: 1806: 1786: 1766: 1731: 1705: 1676: 1611: 1587: 1567: 1538: 1512: 1483: 1463: 1443: 1423: 1403: 1382: 1361: 1339: 1318: 1290: 1270: 1250: 1196: 1131: 1090: 1045: 1012: 982: 960: 925: 890: 841: 778: 753: 718: 690: 668: 642: 599: 533: 513: 446: 401: 368: 348: 272: 239: 212: 177: 153: 126: 99: 7107: 4777:must be paired off with some natural number, say 4287:Now that we have an idea of what the elements of 2545:, the assumption must be false. Thus there is no 9648: 6953:F. William Lawvere; Stephen H. Schanuel (2009). 6849: 6847: 6802: 6770: 4699:non-selfish natural numbers. By definition, the 3831:{\displaystyle A=\mathbb {N} =\{1,2,3,\ldots \}} 3653:is false. Each column records the values of the 1677:{\displaystyle B=\{x\in A\mid x\not \in f(x)\}.} 891:{\displaystyle \xi \in B\iff \xi \notin f(\xi )} 6858:Ernst Zermelo: An Approach to His Life and Work 3743: 318:(colloquially, "there's no largest infinity"). 6766: 6764: 6762: 6760: 19:For other theorems bearing Cantor's name, see 7904: 7244: 7093: 6844: 6830:. Oxford University Press. pp. 118–119. 6825: 6798: 6796: 3353:; the columns are ordered by the argument to 600:{\displaystyle B=\{x\in A\mid x\notin f(x)\}} 6821: 6819: 5455:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5416:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5355:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5294:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5255:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5187:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5152:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 5054:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4757:as an element. If the mapping is bijective, 4730:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4590: 4572: 4555: 4537: 4520: 4502: 4485: 4473: 4433:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4376:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4315:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4248: 4225: 4219: 4195: 4188:, e.g. the set of all positive even numbers 4159:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 4113: 4104: 4080: 4074: 4056: 4050: 4038: 4032: 4026: 4020: 4002: 3996: 3984: 3975: 3937:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 3902:{\displaystyle {\mathcal {P}}(\mathbb {N} )} 3825: 3801: 3272: 3240: 2762: 2756: 1668: 1635: 1126: 1120: 594: 561: 6757: 5713:{\displaystyle |{\mathcal {P}}(V)|\leq |V|} 9672:Theorems in the foundations of mathematics 8096: 7911: 7897: 7251: 7237: 7100: 7086: 6961:. Cambridge University Press. Session 29. 6793: 5976: 5972: 5861: 5857: 5581:{\displaystyle |{\mathcal {P}}(X)|>|X|} 2861:Another way to think of the proof is that 2471: 2467: 2412: 2408: 869: 865: 817: 813: 6816: 6083: 6067: 5815:exists, then considering its Russell set 5789: 5767: 5474: 5445: 5406: 5374: 5345: 5313: 5284: 5245: 5213: 5177: 5142: 5044: 5012: 4720: 4629: 4451: 4423: 4391: 4366: 4334: 4305: 4244: 4174: 4149: 3965: 3927: 3892: 3853: 3794: 3278:{\displaystyle A=\{x_{1},x_{2},\ldots \}} 4660:. Other natural numbers are paired with 1687:This means, by definition, that for all 1091:{\displaystyle g:A\to {\mathcal {P}}(A)} 447:{\displaystyle f:A\to {\mathcal {P}}(A)} 25: 6134:whose values are 2-valued functions on 5262:cannot be equal. We also know that the 247:subsets, and the theorem holds because 196:of the number of subsets. Counting the 69:question marks, boxes, or other symbols 16:Every set is smaller than its power set 9649: 7918: 6911: 6364:and that there exists an endomorphism 5159:, so the mapping still does not cover 4405:with an element from the infinite set 1208:By definition of cardinality, we have 643:{\displaystyle B\in {\mathcal {P}}(A)} 7892: 7232: 7081: 7059: 6777:Springer Science & Business Media 5608:. On the other hand, all elements of 4797:. However, this causes a problem. If 4668:. Likewise, 3 and 4 are non-selfish. 4322:are, let us attempt to pair off each 7012: 6214:, and therefore it differs from phi- 5491: 3517:of this table thus records whether 3148:Because of the double occurrence of 1907:did not include themselves. For all 6806:Set Theory as a Computational Logic 6740:Cantor's first uncountability proof 6568:. In other words, for every object 5939:above, which in turn entailed that 13: 6489: 6349: 6305: 6261: 6236: 5675: 5617: 5543: 5436: 5397: 5336: 5275: 5236: 5168: 5133: 5035: 4711: 4620: 4414: 4357: 4296: 4140: 3956: 3918: 3883: 2831: 1177: 1074: 1029: 917: 626: 494: 430: 385: 14: 9693: 7034: 5634:{\displaystyle {\mathcal {P}}(V)} 3978: 3471:records a true/false bit whether 3424:{\displaystyle f(x_{1}),f(x_{2})} 1863:was constructed from elements of 1046:{\displaystyle {\mathcal {P}}(A)} 402:{\displaystyle {\mathcal {P}}(A)} 21:Cantor's theorem (disambiguation) 9630: 7282: 6854:Heinz-Dieter Ebbinghaus (2007). 6745:Controversy over Cantor's theory 6699:must leave out at least one map 6619:{\displaystyle f:T\times T\to Y} 6535:{\displaystyle f:T\times T\to Y} 6453:{\displaystyle \alpha \circ y=y} 5641:are sets, and thus contained in 7168:Gödel's incompleteness theorems 6542:can parameterize all morphisms 1053:exist. For example, a function 7258: 6933: 6905: 6880: 6709: 6683: 6674: 6662: 6636: 6610: 6552: 6526: 6497:{\displaystyle {\mathcal {C}}} 6412: 6389:{\displaystyle \alpha :Y\to Y} 6380: 6357:{\displaystyle {\mathcal {C}}} 6313:{\displaystyle {\mathcal {C}}} 6269:{\displaystyle {\mathcal {C}}} 6118:for the uncountability of the 6022: 5977: 5973: 5858: 5706: 5698: 5690: 5686: 5680: 5669: 5628: 5622: 5574: 5566: 5558: 5554: 5548: 5537: 5449: 5441: 5410: 5402: 5349: 5341: 5288: 5280: 5249: 5241: 5181: 5173: 5146: 5138: 5048: 5040: 4724: 4716: 4633: 4625: 4567: 4532: 4497: 4468: 4427: 4419: 4370: 4362: 4309: 4301: 4153: 4145: 3969: 3961: 3931: 3923: 3909:. Let us see a sample of what 3896: 3888: 3640: 3634: 3539: 3533: 3418: 3405: 3396: 3383: 3190: 3184: 3025:, thus the element mapping to 2845: 2842: 2836: 2826: 2814: 2808: 2587: 2581: 2507: 2501: 2487: 2481: 2468: 2428: 2422: 2409: 2358: 2352: 2254: 2248: 2199: 2193: 2170: 2164: 2109: 2103: 2054: 2048: 2025: 2019: 1990: 1984: 1955: 1949: 1830: 1824: 1761: 1755: 1665: 1659: 1562: 1556: 1507: 1501: 1245: 1239: 1227: 1221: 1191: 1188: 1182: 1172: 1160: 1154: 1114: 1108: 1085: 1079: 1069: 1040: 1034: 949: 943: 914: 885: 879: 866: 836: 833: 827: 814: 801: 742: 736: 637: 631: 591: 585: 508: 505: 499: 489: 477: 471: 441: 435: 425: 396: 390: 1: 9591:History of mathematical logic 6750: 6692:{\displaystyle f(-,x):T\to Y} 6242:Lawvere's fixed-point theorem 6138:, then the 2-valued function 5462:is strictly greater than the 4937:. Therefore, no such element 4166:contains infinite subsets of 3618:where the table records that 3373:, i.e. the column labels are 609:axiom schema of specification 9516:Primitive recursive function 7163:Gödel's completeness theorem 6828:Beyond the Limits of Thought 6276:be such a category, and let 6168:has a very similar proof in 5824:leads to the contradiction: 5488:, proving Cantor's theorem. 5481:{\displaystyle \mathbb {N} } 5381:{\displaystyle \mathbb {N} } 5320:{\displaystyle \mathbb {N} } 5220:{\displaystyle \mathbb {N} } 5019:{\displaystyle \mathbb {N} } 4398:{\displaystyle \mathbb {N} } 4341:{\displaystyle \mathbb {N} } 4277:{\displaystyle \varnothing } 4181:{\displaystyle \mathbb {N} } 3860:{\displaystyle \mathbb {N} } 2260:{\displaystyle x\notin f(x)} 2176:{\displaystyle x\notin f(x)} 1996:{\displaystyle x\notin f(x)} 1767:{\displaystyle x\notin f(x)} 669:{\displaystyle B\subseteq A} 301:Cardinality of the continuum 30:The cardinality of the set { 7: 7047:Encyclopedia of Mathematics 6728: 6626:, an attempt to write maps 6122:also first appears (he had 1298:if and only if there is an 10: 9698: 8580:Schröder–Bernstein theorem 8307:Monadic predicate calculus 7966:Foundations of mathematics 7749:von Neumann–Bernays–Gödel 7151:Foundations of mathematics 6900:International Logic Review 6735:Schröder–Bernstein theorem 6460:. Then there is no object 6252:in the following way: let 6109: 6043:unrestricted comprehension 5901:This argument is known as 3778:Without loss of generality 3045:must not be an element of 1132:{\displaystyle g(x)=\{x\}} 273:{\displaystyle 2^{n}>n} 18: 9626: 9613:Philosophy of mathematics 9562:Automated theorem proving 9544: 9439: 9271: 9164: 9016: 8733: 8709: 8687:Von Neumann–Bernays–Gödel 8632: 8526: 8430: 8328: 8319: 8246: 8181: 8087: 8009: 7926: 7813: 7776: 7688: 7578: 7550:One-to-one correspondence 7466: 7407: 7291: 7280: 7266: 7119: 6803:Lawrence Paulson (1992). 6771:Abhijit Dasgupta (2013). 6171:Principles of Mathematics 6158:) is not in the range of 6130:is a function defined on 3736:could not do it, whereas 3646:{\displaystyle x\in f(x)} 3545:{\displaystyle x\in f(x)} 3196:{\displaystyle x\in f(x)} 2599:{\displaystyle f(\xi )=B} 2564:{\displaystyle \xi \in A} 2495:(by assumption that  2370:{\displaystyle f(\xi )=B} 2335:{\displaystyle \xi \in A} 2141:{\displaystyle x\notin B} 2115:{\displaystyle x\in f(x)} 2031:{\displaystyle x\in f(x)} 1961:{\displaystyle x\in f(x)} 961:{\displaystyle f(\xi )=B} 754:{\displaystyle f(\xi )=B} 719:{\displaystyle \xi \in A} 312:philosophy of mathematics 306:The theorem is named for 7193:Löwenheim–Skolem theorem 6421:{\displaystyle y:1\to Y} 6296:be a terminal object in 5924:restricted comprehension 5301:cannot be less than the 5201:we have proven that the 3726:automated theorem prover 2606: ; in other words, 1843:cannot be equal because 321: 220:elements has a total of 200:as a subset, a set with 9263:Self-verifying theories 9084:Tarski's axiomatization 8035:Tarski's undefinability 8030:incompleteness theorems 7218:Use–mention distinction 6176:propositional functions 5930:) in the definition of 5498:paradoxes of set theory 2626:is not in the image of 2436:(by definition of  1431:(that maps elements in 990:is not surjective, via 900:universal instantiation 161:has a strictly greater 9637:Mathematics portal 9248:Proof of impossibility 8896:propositional variable 8206:Propositional calculus 7508:Constructible universe 7328:Constructibility (V=L) 7213:Type–token distinction 6912:Cantor, Georg (1891), 6826:Graham Priest (2002). 6719: 6718:{\displaystyle T\to Y} 6693: 6646: 6645:{\displaystyle T\to Y} 6620: 6582: 6562: 6561:{\displaystyle T\to Y} 6536: 6498: 6474: 6454: 6422: 6390: 6358: 6334: 6314: 6290: 6270: 6093: 6032: 5892: 5802: 5714: 5655: 5635: 5602: 5582: 5523: 5482: 5456: 5417: 5382: 5356: 5321: 5295: 5256: 5221: 5199:proof by contradiction 5188: 5153: 5118: 5098: 5078: 5055: 5020: 4994: 4971: 4951: 4931: 4911: 4891: 4871: 4851: 4831: 4811: 4791: 4771: 4751: 4731: 4689: 4643: 4434: 4399: 4377: 4342: 4316: 4278: 4255: 4182: 4160: 4123: 3938: 3903: 3861: 3832: 3766: 3715: 3695: 3671: 3647: 3612: 3592: 3572: 3571:{\displaystyle x\in A} 3546: 3511: 3491: 3490:{\displaystyle x\in y} 3465: 3445: 3425: 3367: 3347: 3323: 3305:is assumed to admit a 3299: 3279: 3221: 3197: 3162: 3139: 3119: 3099: 3079: 3059: 3039: 3019: 2999: 2979: 2959: 2939: 2915: 2895: 2875: 2852: 2789: 2769: 2743: 2723: 2700: 2680: 2660: 2640: 2620: 2600: 2565: 2532: 2377:implies the following 2371: 2336: 2307: 2287: 2286:{\displaystyle x\in B} 2261: 2226: 2206: 2177: 2142: 2116: 2081: 2061: 2032: 1997: 1962: 1927: 1926:{\displaystyle x\in A} 1901: 1877: 1857: 1837: 1808: 1788: 1768: 1733: 1732:{\displaystyle x\in B} 1707: 1706:{\displaystyle x\in A} 1678: 1613: 1589: 1569: 1546:. Recalling that each 1540: 1539:{\displaystyle x\in A} 1514: 1485: 1465: 1445: 1425: 1405: 1384: 1363: 1341: 1320: 1292: 1272: 1252: 1198: 1133: 1092: 1047: 1014: 984: 962: 927: 892: 843: 780: 755: 720: 692: 670: 644: 601: 535: 515: 448: 403: 370: 350: 274: 241: 214: 179: 155: 128: 101: 57:This article contains 51: 9506:Kolmogorov complexity 9459:Computably enumerable 9359:Model complete theory 9151:Principia Mathematica 8211:Propositional formula 8040:Banach–Tarski paradox 7731:Principia Mathematica 7565:Transfinite induction 7424:(i.e. set difference) 6720: 6694: 6647: 6621: 6583: 6563: 6537: 6504:such that a morphism 6499: 6475: 6455: 6423: 6391: 6359: 6335: 6315: 6291: 6271: 6094: 6033: 5893: 5803: 5715: 5656: 5636: 5603: 5583: 5524: 5483: 5457: 5418: 5383: 5357: 5322: 5296: 5257: 5222: 5189: 5154: 5119: 5099: 5079: 5056: 5021: 4995: 4972: 4952: 4932: 4912: 4892: 4872: 4852: 4832: 4812: 4792: 4772: 4752: 4732: 4690: 4644: 4435: 4400: 4378: 4348:with each element of 4343: 4317: 4279: 4256: 4183: 4161: 4124: 3939: 3904: 3862: 3833: 3767: 3748:is countably infinite 3716: 3696: 3672: 3648: 3613: 3593: 3573: 3547: 3512: 3492: 3466: 3446: 3426: 3368: 3348: 3324: 3300: 3280: 3222: 3198: 3163: 3140: 3120: 3100: 3080: 3060: 3040: 3020: 3000: 2980: 2960: 2940: 2916: 2896: 2876: 2853: 2790: 2770: 2768:{\displaystyle \{x\}} 2749:to the singleton set 2744: 2724: 2701: 2681: 2661: 2641: 2621: 2601: 2566: 2533: 2372: 2337: 2308: 2293:by the definition of 2288: 2262: 2227: 2207: 2178: 2143: 2117: 2082: 2062: 2033: 1998: 1963: 1928: 1902: 1878: 1858: 1838: 1809: 1789: 1769: 1734: 1708: 1679: 1614: 1590: 1570: 1541: 1515: 1491:that is not equal to 1486: 1466: 1446: 1426: 1406: 1385: 1364: 1342: 1321: 1293: 1273: 1253: 1199: 1134: 1093: 1048: 1015: 985: 963: 928: 893: 844: 781: 756: 721: 693: 671: 645: 602: 536: 516: 458:. As a consequence, 449: 404: 371: 351: 282:non-negative integers 275: 242: 240:{\displaystyle 2^{n}} 215: 180: 156: 129: 102: 29: 9454:Church–Turing thesis 9441:Computability theory 8650:continuum hypothesis 8168:Square of opposition 8026:Gödel's completeness 7805:Burali-Forti paradox 7560:Set-builder notation 7513:Continuum hypothesis 7453:Symmetric difference 7136:Church–Turing thesis 7130:Entscheidungsproblem 7009:(Paperback edition). 6898:. Also published in 6779:. pp. 362–363. 6703: 6656: 6652:as maps of the form 6630: 6592: 6572: 6546: 6508: 6484: 6464: 6432: 6400: 6368: 6344: 6324: 6300: 6280: 6256: 6210:is false or true of 6182:be the correlate of 6053: 5946: 5831: 5746: 5665: 5645: 5612: 5592: 5533: 5513: 5470: 5431: 5392: 5370: 5331: 5309: 5270: 5231: 5209: 5163: 5128: 5108: 5088: 5068: 5030: 5008: 4984: 4961: 4941: 4921: 4901: 4881: 4861: 4841: 4821: 4801: 4781: 4761: 4741: 4706: 4679: 4447: 4409: 4387: 4352: 4330: 4291: 4268: 4192: 4170: 4135: 3951: 3913: 3878: 3849: 3784: 3756: 3705: 3685: 3661: 3622: 3602: 3582: 3556: 3521: 3501: 3475: 3455: 3435: 3377: 3357: 3337: 3313: 3289: 3231: 3211: 3172: 3152: 3129: 3109: 3089: 3069: 3049: 3029: 3009: 2989: 2969: 2949: 2929: 2905: 2885: 2865: 2799: 2779: 2753: 2733: 2713: 2690: 2670: 2650: 2630: 2610: 2575: 2549: 2543:reductio ad absurdum 2388: 2346: 2320: 2297: 2271: 2236: 2216: 2205:{\displaystyle f(x)} 2187: 2152: 2126: 2091: 2071: 2060:{\displaystyle f(x)} 2042: 2007: 1972: 1937: 1911: 1891: 1867: 1847: 1836:{\displaystyle f(x)} 1818: 1798: 1778: 1743: 1717: 1691: 1626: 1603: 1579: 1568:{\displaystyle f(x)} 1550: 1524: 1513:{\displaystyle f(x)} 1495: 1475: 1455: 1435: 1415: 1395: 1374: 1353: 1331: 1310: 1282: 1262: 1212: 1145: 1102: 1057: 1024: 1004: 992:reductio ad absurdum 974: 937: 908: 853: 792: 770: 730: 704: 700:Then there exists a 682: 654: 615: 552: 525: 462: 413: 380: 360: 340: 251: 224: 204: 169: 142: 115: 91: 9608:Mathematical object 9499:P versus NP problem 9464:Computable function 9258:Reverse mathematics 9184:Logical consequence 9061:primitive recursive 9056:elementary function 8829:Free/bound variable 8682:Tarski–Grothendieck 8201:Logical connectives 8131:Logical equivalence 7981:Logical consequence 7766:Tarski–Grothendieck 6930:, E. Zermelo, 1932. 6588:and every morphism 6218:for every value of 3732:noted in 1992 that 3677:coincides with the 3168:in the expression " 3125:must be false; and 2706:is not surjective. 1597:Cantor diagonal set 842:{\displaystyle A\ } 334: —  9657:1891 introductions 9406:Transfer principle 9369:Semantics of logic 9354:Categorical theory 9330:Non-standard model 8844:Logical connective 7971:Information theory 7920:Mathematical logic 7355:Limitation of size 7064:"Cantor's Theorem" 7061:Weisstein, Eric W. 6993:, New York, 1974. 6715: 6689: 6642: 6616: 6578: 6558: 6532: 6494: 6470: 6450: 6418: 6386: 6354: 6330: 6310: 6286: 6266: 6231:Zermelo set theory 6089: 6028: 5888: 5798: 5710: 5651: 5631: 5598: 5578: 5519: 5478: 5452: 5413: 5378: 5352: 5317: 5291: 5252: 5217: 5184: 5149: 5114: 5094: 5074: 5064:Note that the set 5051: 5016: 4990: 4967: 4947: 4927: 4907: 4887: 4867: 4847: 4827: 4807: 4787: 4767: 4747: 4727: 4685: 4639: 4612: 4430: 4395: 4373: 4338: 4312: 4274: 4251: 4178: 4156: 4119: 3934: 3899: 3857: 3828: 3774:countably infinite 3762: 3711: 3691: 3667: 3655:indicator function 3643: 3608: 3588: 3568: 3542: 3507: 3487: 3461: 3441: 3421: 3363: 3343: 3319: 3295: 3275: 3217: 3193: 3158: 3135: 3115: 3095: 3075: 3055: 3035: 3015: 2995: 2975: 2955: 2935: 2925:, some element of 2911: 2891: 2871: 2848: 2785: 2765: 2739: 2719: 2696: 2676: 2656: 2636: 2616: 2596: 2561: 2528: 2526: 2367: 2332: 2303: 2283: 2267:by assumption and 2257: 2222: 2202: 2173: 2148:by definition. If 2138: 2122:by assumption and 2112: 2077: 2057: 2028: 1993: 1958: 1923: 1897: 1873: 1853: 1833: 1804: 1784: 1764: 1729: 1703: 1674: 1609: 1585: 1565: 1536: 1510: 1481: 1461: 1441: 1421: 1401: 1380: 1359: 1337: 1316: 1304:bijective function 1300:injective function 1288: 1268: 1248: 1194: 1129: 1088: 1043: 1010: 980: 958: 923: 888: 849:, we deduce   839: 776: 751: 716: 688: 666: 640: 597: 547: 531: 521:holds for any set 511: 444: 399: 366: 356:be a map from set 346: 332: 270: 237: 210: 175: 154:{\displaystyle A,} 151: 127:{\displaystyle A,} 124: 97: 59:special characters 52: 9644: 9643: 9576:Abstract category 9379:Theories of truth 9189:Rule of inference 9179:Natural deduction 9160: 9159: 8705: 8704: 8410:Cartesian product 8315: 8314: 8221:Many-valued logic 8196:Boolean functions 8079:Russell's paradox 8054:diagonal argument 7951:First-order logic 7886: 7885: 7795:Russell's paradox 7744:Zermelo–Fraenkel 7645:Dedekind-infinite 7518:Diagonal argument 7417:Cartesian product 7274:Set (mathematics) 7226: 7225: 7007:978-1-61427-131-4 6968:978-0-521-89485-2 6896:978-0-8218-7360-1 6873:978-3-540-49553-6 6837:978-0-19-925405-7 6786:978-1-4614-8854-5 6581:{\displaystyle T} 6473:{\displaystyle T} 6333:{\displaystyle Y} 6289:{\displaystyle 1} 6206:according as phi- 6198:does not hold of 6116:diagonal argument 5903:Russell's paradox 5729:identity function 5654:{\displaystyle V} 5601:{\displaystyle X} 5522:{\displaystyle V} 5492:Related paradoxes 5117:{\displaystyle x} 5097:{\displaystyle x} 5077:{\displaystyle B} 4993:{\displaystyle B} 4970:{\displaystyle B} 4950:{\displaystyle b} 4930:{\displaystyle B} 4910:{\displaystyle B} 4890:{\displaystyle b} 4870:{\displaystyle B} 4850:{\displaystyle b} 4830:{\displaystyle B} 4810:{\displaystyle b} 4790:{\displaystyle b} 4770:{\displaystyle B} 4750:{\displaystyle B} 4688:{\displaystyle B} 4261:, along with the 3765:{\displaystyle A} 3714:{\displaystyle B} 3694:{\displaystyle B} 3679:logically negated 3670:{\displaystyle B} 3611:{\displaystyle D} 3591:{\displaystyle B} 3510:{\displaystyle D} 3464:{\displaystyle y} 3444:{\displaystyle x} 3366:{\displaystyle f} 3346:{\displaystyle A} 3322:{\displaystyle y} 3298:{\displaystyle A} 3285:, in this order. 3220:{\displaystyle x} 3205:diagonal argument 3161:{\displaystyle x} 3138:{\displaystyle f} 3118:{\displaystyle B} 3098:{\displaystyle A} 3078:{\displaystyle B} 3058:{\displaystyle B} 3038:{\displaystyle B} 3018:{\displaystyle B} 2998:{\displaystyle B} 2978:{\displaystyle B} 2958:{\displaystyle B} 2938:{\displaystyle A} 2914:{\displaystyle f} 2894:{\displaystyle A} 2874:{\displaystyle B} 2788:{\displaystyle A} 2742:{\displaystyle x} 2722:{\displaystyle A} 2699:{\displaystyle f} 2679:{\displaystyle A} 2659:{\displaystyle f} 2639:{\displaystyle f} 2619:{\displaystyle B} 2519: 2496: 2445: 2437: 2306:{\displaystyle B} 2225:{\displaystyle B} 2080:{\displaystyle B} 1900:{\displaystyle f} 1876:{\displaystyle A} 1856:{\displaystyle B} 1807:{\displaystyle B} 1787:{\displaystyle x} 1612:{\displaystyle f} 1588:{\displaystyle A} 1484:{\displaystyle A} 1464:{\displaystyle A} 1444:{\displaystyle A} 1424:{\displaystyle f} 1404:{\displaystyle A} 1383:{\displaystyle Y} 1362:{\displaystyle X} 1340:{\displaystyle Y} 1319:{\displaystyle X} 1291:{\displaystyle Y} 1271:{\displaystyle X} 1258:for any two sets 1013:{\displaystyle A} 983:{\displaystyle f} 800: 779:{\displaystyle x} 691:{\displaystyle f} 545: 534:{\displaystyle A} 376:to its power set 369:{\displaystyle A} 349:{\displaystyle f} 330: 213:{\displaystyle n} 178:{\displaystyle A} 107:, the set of all 100:{\displaystyle A} 65:rendering support 9689: 9677:Cardinal numbers 9635: 9634: 9586:History of logic 9581:Category of sets 9474:Decision problem 9253:Ordinal analysis 9194:Sequent calculus 9092:Boolean algebras 9032: 9031: 9006: 8977:logical/constant 8731: 8730: 8717: 8640:Zermelo–Fraenkel 8391:Set operations: 8326: 8325: 8263: 8094: 8093: 8074:Löwenheim–Skolem 7961:Formal semantics 7913: 7906: 7899: 7890: 7889: 7868:Bertrand Russell 7858:John von Neumann 7843:Abraham Fraenkel 7838:Richard Dedekind 7800:Suslin's problem 7711:Cantor's theorem 7428:De Morgan's laws 7286: 7253: 7246: 7239: 7230: 7229: 7146:Effective method 7124:Cantor's theorem 7102: 7095: 7088: 7079: 7078: 7074: 7073: 7055: 7042:"Cantor theorem" 7030: 6986:Naive Set Theory 6973: 6972: 6960: 6950: 6944: 6937: 6931: 6925: 6909: 6903: 6884: 6878: 6877: 6861: 6851: 6842: 6841: 6823: 6814: 6813: 6811: 6800: 6791: 6790: 6768: 6724: 6722: 6721: 6716: 6698: 6696: 6695: 6690: 6651: 6649: 6648: 6643: 6625: 6623: 6622: 6617: 6587: 6585: 6584: 6579: 6567: 6565: 6564: 6559: 6541: 6539: 6538: 6533: 6503: 6501: 6500: 6495: 6493: 6492: 6479: 6477: 6476: 6471: 6459: 6457: 6456: 6451: 6427: 6425: 6424: 6419: 6395: 6393: 6392: 6387: 6363: 6361: 6360: 6355: 6353: 6352: 6340:is an object in 6339: 6337: 6336: 6331: 6319: 6317: 6316: 6311: 6309: 6308: 6295: 6293: 6292: 6287: 6275: 6273: 6272: 6267: 6265: 6264: 6186:. Then "not-phi- 6166:Bertrand Russell 6098: 6096: 6095: 6090: 6088: 6084: 6037: 6035: 6034: 6029: 6021: 6020: 6008: 6007: 5989: 5988: 5971: 5970: 5958: 5957: 5926:(as featured in 5897: 5895: 5894: 5889: 5884: 5883: 5871: 5870: 5856: 5855: 5843: 5842: 5807: 5805: 5804: 5799: 5794: 5790: 5758: 5757: 5719: 5717: 5716: 5711: 5709: 5701: 5693: 5679: 5678: 5672: 5660: 5658: 5657: 5652: 5640: 5638: 5637: 5632: 5621: 5620: 5607: 5605: 5604: 5599: 5587: 5585: 5584: 5579: 5577: 5569: 5561: 5547: 5546: 5540: 5528: 5526: 5525: 5520: 5504:Cantor's paradox 5487: 5485: 5484: 5479: 5477: 5461: 5459: 5458: 5453: 5448: 5440: 5439: 5422: 5420: 5419: 5414: 5409: 5401: 5400: 5387: 5385: 5384: 5379: 5377: 5361: 5359: 5358: 5353: 5348: 5340: 5339: 5326: 5324: 5323: 5318: 5316: 5300: 5298: 5297: 5292: 5287: 5279: 5278: 5261: 5259: 5258: 5253: 5248: 5240: 5239: 5226: 5224: 5223: 5218: 5216: 5193: 5191: 5190: 5185: 5180: 5172: 5171: 5158: 5156: 5155: 5150: 5145: 5137: 5136: 5123: 5121: 5120: 5115: 5103: 5101: 5100: 5095: 5083: 5081: 5080: 5075: 5060: 5058: 5057: 5052: 5047: 5039: 5038: 5025: 5023: 5022: 5017: 5015: 4999: 4997: 4996: 4991: 4976: 4974: 4973: 4968: 4956: 4954: 4953: 4948: 4936: 4934: 4933: 4928: 4916: 4914: 4913: 4908: 4896: 4894: 4893: 4888: 4876: 4874: 4873: 4868: 4856: 4854: 4853: 4848: 4836: 4834: 4833: 4828: 4816: 4814: 4813: 4808: 4796: 4794: 4793: 4788: 4776: 4774: 4773: 4768: 4756: 4754: 4753: 4748: 4736: 4734: 4733: 4728: 4723: 4715: 4714: 4694: 4692: 4691: 4686: 4648: 4646: 4645: 4640: 4632: 4624: 4623: 4617: 4616: 4454: 4439: 4437: 4436: 4431: 4426: 4418: 4417: 4404: 4402: 4401: 4396: 4394: 4382: 4380: 4379: 4374: 4369: 4361: 4360: 4347: 4345: 4344: 4339: 4337: 4321: 4319: 4318: 4313: 4308: 4300: 4299: 4283: 4281: 4280: 4275: 4260: 4258: 4257: 4252: 4247: 4187: 4185: 4184: 4179: 4177: 4165: 4163: 4162: 4157: 4152: 4144: 4143: 4128: 4126: 4125: 4120: 3968: 3960: 3959: 3943: 3941: 3940: 3935: 3930: 3922: 3921: 3908: 3906: 3905: 3900: 3895: 3887: 3886: 3866: 3864: 3863: 3858: 3856: 3837: 3835: 3834: 3829: 3797: 3771: 3769: 3768: 3763: 3730:Lawrence Paulson 3720: 3718: 3717: 3712: 3700: 3698: 3697: 3692: 3676: 3674: 3673: 3668: 3652: 3650: 3649: 3644: 3617: 3615: 3614: 3609: 3597: 3595: 3594: 3589: 3577: 3575: 3574: 3569: 3551: 3549: 3548: 3543: 3516: 3514: 3513: 3508: 3496: 3494: 3493: 3488: 3470: 3468: 3467: 3462: 3450: 3448: 3447: 3442: 3430: 3428: 3427: 3422: 3417: 3416: 3395: 3394: 3372: 3370: 3369: 3364: 3352: 3350: 3349: 3344: 3328: 3326: 3325: 3320: 3304: 3302: 3301: 3296: 3284: 3282: 3281: 3276: 3265: 3264: 3252: 3251: 3226: 3224: 3223: 3218: 3202: 3200: 3199: 3194: 3167: 3165: 3164: 3159: 3145:cannot be onto. 3144: 3142: 3141: 3136: 3124: 3122: 3121: 3116: 3104: 3102: 3101: 3096: 3084: 3082: 3081: 3076: 3064: 3062: 3061: 3056: 3044: 3042: 3041: 3036: 3024: 3022: 3021: 3016: 3004: 3002: 3001: 2996: 2984: 2982: 2981: 2976: 2964: 2962: 2961: 2956: 2944: 2942: 2941: 2936: 2920: 2918: 2917: 2912: 2900: 2898: 2897: 2892: 2880: 2878: 2877: 2872: 2857: 2855: 2854: 2849: 2835: 2834: 2794: 2792: 2791: 2786: 2774: 2772: 2771: 2766: 2748: 2746: 2745: 2740: 2728: 2726: 2725: 2720: 2705: 2703: 2702: 2697: 2685: 2683: 2682: 2677: 2665: 2663: 2662: 2657: 2645: 2643: 2642: 2637: 2625: 2623: 2622: 2617: 2605: 2603: 2602: 2597: 2570: 2568: 2567: 2562: 2537: 2535: 2534: 2529: 2527: 2520: 2517: 2497: 2494: 2491: 2446: 2443: 2438: 2435: 2432: 2376: 2374: 2373: 2368: 2341: 2339: 2338: 2333: 2312: 2310: 2309: 2304: 2292: 2290: 2289: 2284: 2266: 2264: 2263: 2258: 2231: 2229: 2228: 2223: 2211: 2209: 2208: 2203: 2182: 2180: 2179: 2174: 2147: 2145: 2144: 2139: 2121: 2119: 2118: 2113: 2086: 2084: 2083: 2078: 2066: 2064: 2063: 2058: 2037: 2035: 2034: 2029: 2002: 2000: 1999: 1994: 1967: 1965: 1964: 1959: 1932: 1930: 1929: 1924: 1906: 1904: 1903: 1898: 1882: 1880: 1879: 1874: 1862: 1860: 1859: 1854: 1842: 1840: 1839: 1834: 1813: 1811: 1810: 1805: 1793: 1791: 1790: 1785: 1773: 1771: 1770: 1765: 1738: 1736: 1735: 1730: 1712: 1710: 1709: 1704: 1683: 1681: 1680: 1675: 1618: 1616: 1615: 1610: 1594: 1592: 1591: 1586: 1574: 1572: 1571: 1566: 1545: 1543: 1542: 1537: 1519: 1517: 1516: 1511: 1490: 1488: 1487: 1482: 1470: 1468: 1467: 1462: 1450: 1448: 1447: 1442: 1430: 1428: 1427: 1422: 1410: 1408: 1407: 1402: 1390: 1389: 1387: 1386: 1381: 1368: 1366: 1365: 1360: 1348: 1346: 1344: 1343: 1338: 1325: 1323: 1322: 1317: 1297: 1295: 1294: 1289: 1277: 1275: 1274: 1269: 1257: 1255: 1254: 1249: 1203: 1201: 1200: 1195: 1181: 1180: 1138: 1136: 1135: 1130: 1097: 1095: 1094: 1089: 1078: 1077: 1052: 1050: 1049: 1044: 1033: 1032: 1019: 1017: 1016: 1011: 989: 987: 986: 981: 967: 965: 964: 959: 932: 930: 929: 924: 897: 895: 894: 889: 848: 846: 845: 840: 798: 785: 783: 782: 777: 760: 758: 757: 752: 725: 723: 722: 717: 697: 695: 694: 689: 675: 673: 672: 667: 649: 647: 646: 641: 630: 629: 606: 604: 603: 598: 540: 538: 537: 532: 520: 518: 517: 512: 498: 497: 453: 451: 450: 445: 434: 433: 408: 406: 405: 400: 389: 388: 375: 373: 372: 367: 355: 353: 352: 347: 335: 331:Theorem (Cantor) 279: 277: 276: 271: 263: 262: 246: 244: 243: 238: 236: 235: 219: 217: 216: 211: 184: 182: 181: 176: 160: 158: 157: 152: 133: 131: 130: 125: 106: 104: 103: 98: 82:Cantor's theorem 76:In mathematical 9697: 9696: 9692: 9691: 9690: 9688: 9687: 9686: 9662:1891 in science 9647: 9646: 9645: 9640: 9629: 9622: 9567:Category theory 9557:Algebraic logic 9540: 9511:Lambda calculus 9449:Church encoding 9435: 9411:Truth predicate 9267: 9233:Complete theory 9156: 9025: 9021: 9017: 9012: 9004: 8724: and  8720: 8715: 8701: 8677:New Foundations 8645:axiom of choice 8628: 8590:Gödel numbering 8530: and  8522: 8426: 8311: 8261: 8242: 8191:Boolean algebra 8177: 8141:Equiconsistency 8106:Classical logic 8083: 8064:Halting problem 8052: and  8028: and  8016: and  8015: 8010:Theorems ( 8005: 7922: 7917: 7887: 7882: 7809: 7788: 7772: 7737:New Foundations 7684: 7574: 7493:Cardinal number 7476: 7462: 7403: 7287: 7278: 7262: 7257: 7227: 7222: 7115: 7113:metamathematics 7106: 7040: 7037: 7028: 6991:Springer-Verlag 6977: 6976: 6969: 6951: 6947: 6938: 6934: 6910: 6906: 6885: 6881: 6874: 6852: 6845: 6838: 6824: 6817: 6809: 6801: 6794: 6787: 6769: 6758: 6753: 6731: 6704: 6701: 6700: 6657: 6654: 6653: 6631: 6628: 6627: 6593: 6590: 6589: 6573: 6570: 6569: 6547: 6544: 6543: 6509: 6506: 6505: 6488: 6487: 6485: 6482: 6481: 6465: 6462: 6461: 6433: 6430: 6429: 6428:that satisfies 6401: 6398: 6397: 6369: 6366: 6365: 6348: 6347: 6345: 6342: 6341: 6325: 6322: 6321: 6320:. Suppose that 6304: 6303: 6301: 6298: 6297: 6281: 6278: 6277: 6260: 6259: 6257: 6254: 6253: 6250:finite products 6239: 6237:Generalizations 6112: 6066: 6062: 6054: 6051: 6050: 6016: 6012: 6003: 5999: 5984: 5980: 5966: 5962: 5953: 5949: 5947: 5944: 5943: 5938: 5917: 5879: 5875: 5866: 5862: 5851: 5847: 5838: 5834: 5832: 5829: 5828: 5823: 5766: 5762: 5753: 5749: 5747: 5744: 5743: 5735:of a given set 5705: 5697: 5689: 5674: 5673: 5668: 5666: 5663: 5662: 5646: 5643: 5642: 5616: 5615: 5613: 5610: 5609: 5593: 5590: 5589: 5573: 5565: 5557: 5542: 5541: 5536: 5534: 5531: 5530: 5514: 5511: 5510: 5494: 5473: 5471: 5468: 5467: 5444: 5435: 5434: 5432: 5429: 5428: 5405: 5396: 5395: 5393: 5390: 5389: 5373: 5371: 5368: 5367: 5344: 5335: 5334: 5332: 5329: 5328: 5312: 5310: 5307: 5306: 5283: 5274: 5273: 5271: 5268: 5267: 5244: 5235: 5234: 5232: 5229: 5228: 5212: 5210: 5207: 5206: 5176: 5167: 5166: 5164: 5161: 5160: 5141: 5132: 5131: 5129: 5126: 5125: 5109: 5106: 5105: 5089: 5086: 5085: 5069: 5066: 5065: 5043: 5034: 5033: 5031: 5028: 5027: 5011: 5009: 5006: 5005: 4985: 4982: 4981: 4962: 4959: 4958: 4942: 4939: 4938: 4922: 4919: 4918: 4902: 4899: 4898: 4882: 4879: 4878: 4862: 4859: 4858: 4842: 4839: 4838: 4822: 4819: 4818: 4802: 4799: 4798: 4782: 4779: 4778: 4762: 4759: 4758: 4742: 4739: 4738: 4719: 4710: 4709: 4707: 4704: 4703: 4680: 4677: 4676: 4628: 4619: 4618: 4611: 4610: 4605: 4600: 4594: 4593: 4570: 4565: 4559: 4558: 4535: 4530: 4524: 4523: 4500: 4495: 4489: 4488: 4471: 4466: 4456: 4455: 4450: 4448: 4445: 4444: 4422: 4413: 4412: 4410: 4407: 4406: 4390: 4388: 4385: 4384: 4365: 4356: 4355: 4353: 4350: 4349: 4333: 4331: 4328: 4327: 4304: 4295: 4294: 4292: 4289: 4288: 4269: 4266: 4265: 4243: 4193: 4190: 4189: 4173: 4171: 4168: 4167: 4148: 4139: 4138: 4136: 4133: 4132: 3964: 3955: 3954: 3952: 3949: 3948: 3926: 3917: 3916: 3914: 3911: 3910: 3891: 3882: 3881: 3879: 3876: 3875: 3852: 3850: 3847: 3846: 3840:natural numbers 3793: 3785: 3782: 3781: 3757: 3754: 3753: 3750: 3706: 3703: 3702: 3686: 3683: 3682: 3662: 3659: 3658: 3623: 3620: 3619: 3603: 3600: 3599: 3583: 3580: 3579: 3557: 3554: 3553: 3522: 3519: 3518: 3502: 3499: 3498: 3476: 3473: 3472: 3456: 3453: 3452: 3436: 3433: 3432: 3412: 3408: 3390: 3386: 3378: 3375: 3374: 3358: 3355: 3354: 3338: 3335: 3334: 3314: 3311: 3310: 3290: 3287: 3286: 3260: 3256: 3247: 3243: 3232: 3229: 3228: 3212: 3209: 3208: 3173: 3170: 3169: 3153: 3150: 3149: 3130: 3127: 3126: 3110: 3107: 3106: 3090: 3087: 3086: 3070: 3067: 3066: 3050: 3047: 3046: 3030: 3027: 3026: 3010: 3007: 3006: 2990: 2987: 2986: 2970: 2967: 2966: 2950: 2947: 2946: 2930: 2927: 2926: 2906: 2903: 2902: 2886: 2883: 2882: 2866: 2863: 2862: 2830: 2829: 2800: 2797: 2796: 2780: 2777: 2776: 2754: 2751: 2750: 2734: 2731: 2730: 2714: 2711: 2710: 2691: 2688: 2687: 2671: 2668: 2667: 2651: 2648: 2647: 2631: 2628: 2627: 2611: 2608: 2607: 2576: 2573: 2572: 2550: 2547: 2546: 2525: 2524: 2516: 2493: 2490: 2463: 2451: 2450: 2442: 2434: 2431: 2404: 2391: 2389: 2386: 2385: 2347: 2344: 2343: 2321: 2318: 2317: 2298: 2295: 2294: 2272: 2269: 2268: 2237: 2234: 2233: 2217: 2214: 2213: 2188: 2185: 2184: 2153: 2150: 2149: 2127: 2124: 2123: 2092: 2089: 2088: 2072: 2069: 2068: 2043: 2040: 2039: 2008: 2005: 2004: 1973: 1970: 1969: 1938: 1935: 1934: 1912: 1909: 1908: 1892: 1889: 1888: 1868: 1865: 1864: 1848: 1845: 1844: 1819: 1816: 1815: 1799: 1796: 1795: 1779: 1776: 1775: 1744: 1741: 1740: 1739:if and only if 1718: 1715: 1714: 1692: 1689: 1688: 1627: 1624: 1623: 1604: 1601: 1600: 1580: 1577: 1576: 1575:is a subset of 1551: 1548: 1547: 1525: 1522: 1521: 1496: 1493: 1492: 1476: 1473: 1472: 1456: 1453: 1452: 1436: 1433: 1432: 1416: 1413: 1412: 1396: 1393: 1392: 1375: 1372: 1371: 1369: 1354: 1351: 1350: 1332: 1329: 1328: 1326: 1311: 1308: 1307: 1283: 1280: 1279: 1263: 1260: 1259: 1213: 1210: 1209: 1206: 1176: 1175: 1146: 1143: 1142: 1140: 1103: 1100: 1099: 1073: 1072: 1058: 1055: 1054: 1028: 1027: 1025: 1022: 1021: 1005: 1002: 1001: 995: 975: 972: 971: 969: 938: 935: 934: 909: 906: 905: 903: 854: 851: 850: 793: 790: 789: 771: 768: 767: 762: 731: 728: 727: 705: 702: 701: 699: 698:is surjective. 683: 680: 679: 677: 655: 652: 651: 625: 624: 616: 613: 612: 607:exists via the 553: 550: 549: 543: 526: 523: 522: 493: 492: 463: 460: 459: 429: 428: 414: 411: 410: 384: 383: 381: 378: 377: 361: 358: 357: 341: 338: 337: 333: 324: 316:cardinal number 258: 254: 252: 249: 248: 231: 227: 225: 222: 221: 205: 202: 201: 170: 167: 166: 143: 140: 139: 116: 113: 112: 92: 89: 88: 74: 73: 72: 63:Without proper 24: 17: 12: 11: 5: 9695: 9685: 9684: 9679: 9674: 9669: 9664: 9659: 9642: 9641: 9627: 9624: 9623: 9621: 9620: 9615: 9610: 9605: 9600: 9599: 9598: 9588: 9583: 9578: 9569: 9564: 9559: 9554: 9552:Abstract logic 9548: 9546: 9542: 9541: 9539: 9538: 9533: 9531:Turing machine 9528: 9523: 9518: 9513: 9508: 9503: 9502: 9501: 9496: 9491: 9486: 9481: 9471: 9469:Computable set 9466: 9461: 9456: 9451: 9445: 9443: 9437: 9436: 9434: 9433: 9428: 9423: 9418: 9413: 9408: 9403: 9398: 9397: 9396: 9391: 9386: 9376: 9371: 9366: 9364:Satisfiability 9361: 9356: 9351: 9350: 9349: 9339: 9338: 9337: 9327: 9326: 9325: 9320: 9315: 9310: 9305: 9295: 9294: 9293: 9288: 9281:Interpretation 9277: 9275: 9269: 9268: 9266: 9265: 9260: 9255: 9250: 9245: 9235: 9230: 9229: 9228: 9227: 9226: 9216: 9211: 9201: 9196: 9191: 9186: 9181: 9176: 9170: 9168: 9162: 9161: 9158: 9157: 9155: 9154: 9146: 9145: 9144: 9143: 9138: 9137: 9136: 9131: 9126: 9106: 9105: 9104: 9102:minimal axioms 9099: 9088: 9087: 9086: 9075: 9074: 9073: 9068: 9063: 9058: 9053: 9048: 9035: 9033: 9014: 9013: 9011: 9010: 9009: 9008: 8996: 8991: 8990: 8989: 8984: 8979: 8974: 8964: 8959: 8954: 8949: 8948: 8947: 8942: 8932: 8931: 8930: 8925: 8920: 8915: 8905: 8900: 8899: 8898: 8893: 8888: 8878: 8877: 8876: 8871: 8866: 8861: 8856: 8851: 8841: 8836: 8831: 8826: 8825: 8824: 8819: 8814: 8809: 8799: 8794: 8792:Formation rule 8789: 8784: 8783: 8782: 8777: 8767: 8766: 8765: 8755: 8750: 8745: 8740: 8734: 8728: 8711:Formal systems 8707: 8706: 8703: 8702: 8700: 8699: 8694: 8689: 8684: 8679: 8674: 8669: 8664: 8659: 8654: 8653: 8652: 8647: 8636: 8634: 8630: 8629: 8627: 8626: 8625: 8624: 8614: 8609: 8608: 8607: 8600:Large cardinal 8597: 8592: 8587: 8582: 8577: 8563: 8562: 8561: 8556: 8551: 8536: 8534: 8524: 8523: 8521: 8520: 8519: 8518: 8513: 8508: 8498: 8493: 8488: 8483: 8478: 8473: 8468: 8463: 8458: 8453: 8448: 8443: 8437: 8435: 8428: 8427: 8425: 8424: 8423: 8422: 8417: 8412: 8407: 8402: 8397: 8389: 8388: 8387: 8382: 8372: 8367: 8365:Extensionality 8362: 8360:Ordinal number 8357: 8347: 8342: 8341: 8340: 8329: 8323: 8317: 8316: 8313: 8312: 8310: 8309: 8304: 8299: 8294: 8289: 8284: 8279: 8278: 8277: 8267: 8266: 8265: 8252: 8250: 8244: 8243: 8241: 8240: 8239: 8238: 8233: 8228: 8218: 8213: 8208: 8203: 8198: 8193: 8187: 8185: 8179: 8178: 8176: 8175: 8170: 8165: 8160: 8155: 8150: 8145: 8144: 8143: 8133: 8128: 8123: 8118: 8113: 8108: 8102: 8100: 8091: 8085: 8084: 8082: 8081: 8076: 8071: 8066: 8061: 8056: 8044:Cantor's  8042: 8037: 8032: 8022: 8020: 8007: 8006: 8004: 8003: 7998: 7993: 7988: 7983: 7978: 7973: 7968: 7963: 7958: 7953: 7948: 7943: 7942: 7941: 7930: 7928: 7924: 7923: 7916: 7915: 7908: 7901: 7893: 7884: 7883: 7881: 7880: 7875: 7873:Thoralf Skolem 7870: 7865: 7860: 7855: 7850: 7845: 7840: 7835: 7830: 7825: 7819: 7817: 7811: 7810: 7808: 7807: 7802: 7797: 7791: 7789: 7787: 7786: 7783: 7777: 7774: 7773: 7771: 7770: 7769: 7768: 7763: 7758: 7757: 7756: 7741: 7740: 7739: 7727: 7726: 7725: 7714: 7713: 7708: 7703: 7698: 7692: 7690: 7686: 7685: 7683: 7682: 7677: 7672: 7667: 7658: 7653: 7648: 7638: 7633: 7632: 7631: 7626: 7621: 7611: 7601: 7596: 7591: 7585: 7583: 7576: 7575: 7573: 7572: 7567: 7562: 7557: 7555:Ordinal number 7552: 7547: 7542: 7537: 7536: 7535: 7530: 7520: 7515: 7510: 7505: 7500: 7490: 7485: 7479: 7477: 7475: 7474: 7471: 7467: 7464: 7463: 7461: 7460: 7455: 7450: 7445: 7440: 7435: 7433:Disjoint union 7430: 7425: 7419: 7413: 7411: 7405: 7404: 7402: 7401: 7400: 7399: 7394: 7383: 7382: 7380:Martin's axiom 7377: 7372: 7367: 7362: 7357: 7352: 7347: 7345:Extensionality 7342: 7341: 7340: 7330: 7325: 7324: 7323: 7318: 7313: 7303: 7297: 7295: 7289: 7288: 7281: 7279: 7277: 7276: 7270: 7268: 7264: 7263: 7256: 7255: 7248: 7241: 7233: 7224: 7223: 7221: 7220: 7215: 7210: 7205: 7203:Satisfiability 7200: 7195: 7190: 7188:Interpretation 7185: 7180: 7175: 7170: 7165: 7160: 7159: 7158: 7148: 7143: 7138: 7133: 7126: 7120: 7117: 7116: 7105: 7104: 7097: 7090: 7082: 7076: 7075: 7056: 7036: 7035:External links 7033: 7032: 7031: 7026: 7010: 6975: 6974: 6967: 6945: 6939:A. Kanamori, " 6932: 6904: 6879: 6872: 6843: 6836: 6815: 6792: 6785: 6755: 6754: 6752: 6749: 6748: 6747: 6742: 6737: 6730: 6727: 6714: 6711: 6708: 6688: 6685: 6682: 6679: 6676: 6673: 6670: 6667: 6664: 6661: 6641: 6638: 6635: 6615: 6612: 6609: 6606: 6603: 6600: 6597: 6577: 6557: 6554: 6551: 6531: 6528: 6525: 6522: 6519: 6516: 6513: 6491: 6469: 6449: 6446: 6443: 6440: 6437: 6417: 6414: 6411: 6408: 6405: 6385: 6382: 6379: 6376: 6373: 6351: 6329: 6307: 6285: 6263: 6238: 6235: 6194:)," i.e. "phi- 6146:) = 1 − 6111: 6108: 6087: 6082: 6079: 6076: 6073: 6070: 6065: 6061: 6058: 6039: 6038: 6027: 6024: 6019: 6015: 6011: 6006: 6002: 5998: 5995: 5992: 5987: 5983: 5979: 5975: 5969: 5965: 5961: 5956: 5952: 5934: 5913: 5899: 5898: 5887: 5882: 5878: 5874: 5869: 5865: 5860: 5854: 5850: 5846: 5841: 5837: 5819: 5809: 5808: 5797: 5793: 5788: 5785: 5782: 5779: 5776: 5773: 5770: 5765: 5761: 5756: 5752: 5708: 5704: 5700: 5696: 5692: 5688: 5685: 5682: 5677: 5671: 5650: 5630: 5627: 5624: 5619: 5597: 5576: 5572: 5568: 5564: 5560: 5556: 5553: 5550: 5545: 5539: 5518: 5493: 5490: 5476: 5451: 5447: 5443: 5438: 5412: 5408: 5404: 5399: 5376: 5351: 5347: 5343: 5338: 5315: 5290: 5286: 5282: 5277: 5251: 5247: 5243: 5238: 5215: 5183: 5179: 5175: 5170: 5148: 5144: 5140: 5135: 5113: 5093: 5073: 5050: 5046: 5042: 5037: 5014: 4989: 4966: 4957:which maps to 4946: 4926: 4906: 4886: 4866: 4846: 4826: 4806: 4786: 4766: 4746: 4726: 4722: 4718: 4713: 4695:be the set of 4684: 4650: 4649: 4638: 4635: 4631: 4627: 4622: 4615: 4609: 4606: 4604: 4601: 4599: 4596: 4595: 4592: 4589: 4586: 4583: 4580: 4577: 4574: 4571: 4569: 4566: 4564: 4561: 4560: 4557: 4554: 4551: 4548: 4545: 4542: 4539: 4536: 4534: 4531: 4529: 4526: 4525: 4522: 4519: 4516: 4513: 4510: 4507: 4504: 4501: 4499: 4496: 4494: 4491: 4490: 4487: 4484: 4481: 4478: 4475: 4472: 4470: 4467: 4465: 4462: 4461: 4459: 4453: 4429: 4425: 4421: 4416: 4393: 4372: 4368: 4364: 4359: 4336: 4311: 4307: 4303: 4298: 4273: 4250: 4246: 4242: 4239: 4236: 4233: 4230: 4227: 4224: 4221: 4218: 4215: 4212: 4209: 4206: 4203: 4200: 4197: 4176: 4155: 4151: 4147: 4142: 4130: 4129: 4118: 4115: 4112: 4109: 4106: 4103: 4100: 4097: 4094: 4091: 4088: 4085: 4082: 4079: 4076: 4073: 4070: 4067: 4064: 4061: 4058: 4055: 4052: 4049: 4046: 4043: 4040: 4037: 4034: 4031: 4028: 4025: 4022: 4019: 4016: 4013: 4010: 4007: 4004: 4001: 3998: 3995: 3992: 3989: 3986: 3983: 3980: 3977: 3974: 3971: 3967: 3963: 3958: 3933: 3929: 3925: 3920: 3898: 3894: 3890: 3885: 3855: 3827: 3824: 3821: 3818: 3815: 3812: 3809: 3806: 3803: 3800: 3796: 3792: 3789: 3780:, we may take 3761: 3749: 3742: 3710: 3690: 3666: 3642: 3639: 3636: 3633: 3630: 3627: 3607: 3587: 3567: 3564: 3561: 3541: 3538: 3535: 3532: 3529: 3526: 3506: 3486: 3483: 3480: 3460: 3440: 3420: 3415: 3411: 3407: 3404: 3401: 3398: 3393: 3389: 3385: 3382: 3362: 3342: 3318: 3294: 3274: 3271: 3268: 3263: 3259: 3255: 3250: 3246: 3242: 3239: 3236: 3216: 3192: 3189: 3186: 3183: 3180: 3177: 3157: 3134: 3114: 3094: 3074: 3054: 3034: 3014: 2994: 2974: 2954: 2934: 2910: 2890: 2870: 2847: 2844: 2841: 2838: 2833: 2828: 2825: 2822: 2819: 2816: 2813: 2810: 2807: 2804: 2784: 2764: 2761: 2758: 2738: 2718: 2695: 2675: 2655: 2635: 2615: 2595: 2592: 2589: 2586: 2583: 2580: 2560: 2557: 2554: 2541:Therefore, by 2539: 2538: 2523: 2515: 2512: 2509: 2506: 2503: 2500: 2492: 2489: 2486: 2483: 2480: 2477: 2474: 2470: 2466: 2464: 2462: 2459: 2456: 2453: 2452: 2449: 2441: 2433: 2430: 2427: 2424: 2421: 2418: 2415: 2411: 2407: 2405: 2403: 2400: 2397: 2394: 2393: 2366: 2363: 2360: 2357: 2354: 2351: 2331: 2328: 2325: 2302: 2282: 2279: 2276: 2256: 2253: 2250: 2247: 2244: 2241: 2221: 2201: 2198: 2195: 2192: 2172: 2169: 2166: 2163: 2160: 2157: 2137: 2134: 2131: 2111: 2108: 2105: 2102: 2099: 2096: 2076: 2056: 2053: 2050: 2047: 2027: 2024: 2021: 2018: 2015: 2012: 1992: 1989: 1986: 1983: 1980: 1977: 1957: 1954: 1951: 1948: 1945: 1942: 1922: 1919: 1916: 1896: 1872: 1852: 1832: 1829: 1826: 1823: 1803: 1783: 1763: 1760: 1757: 1754: 1751: 1748: 1728: 1725: 1722: 1702: 1699: 1696: 1685: 1684: 1673: 1670: 1667: 1664: 1661: 1658: 1655: 1652: 1649: 1646: 1643: 1640: 1637: 1634: 1631: 1608: 1584: 1564: 1561: 1558: 1555: 1535: 1532: 1529: 1509: 1506: 1503: 1500: 1480: 1460: 1451:to subsets of 1440: 1420: 1400: 1379: 1358: 1336: 1315: 1287: 1267: 1247: 1244: 1241: 1238: 1235: 1232: 1229: 1226: 1223: 1220: 1217: 1193: 1190: 1187: 1184: 1179: 1174: 1171: 1168: 1165: 1162: 1159: 1156: 1153: 1150: 1141:Consequently, 1128: 1125: 1122: 1119: 1116: 1113: 1110: 1107: 1087: 1084: 1081: 1076: 1071: 1068: 1065: 1062: 1042: 1039: 1036: 1031: 1009: 998:injective maps 979: 957: 954: 951: 948: 945: 942: 922: 919: 916: 913: 887: 884: 881: 878: 875: 872: 868: 864: 861: 858: 838: 835: 832: 829: 826: 823: 820: 816: 812: 809: 806: 803: 797: 775: 750: 747: 744: 741: 738: 735: 715: 712: 709: 687: 665: 662: 659: 639: 636: 633: 628: 623: 620: 596: 593: 590: 587: 584: 581: 578: 575: 572: 569: 566: 563: 560: 557: 544: 530: 510: 507: 504: 501: 496: 491: 488: 485: 482: 479: 476: 473: 470: 467: 443: 440: 437: 432: 427: 424: 421: 418: 398: 395: 392: 387: 365: 345: 328: 323: 320: 269: 266: 261: 257: 234: 230: 209: 174: 150: 147: 123: 120: 96: 67:, you may see 55: 54: 53: 15: 9: 6: 4: 3: 2: 9694: 9683: 9680: 9678: 9675: 9673: 9670: 9668: 9665: 9663: 9660: 9658: 9655: 9654: 9652: 9639: 9638: 9633: 9625: 9619: 9616: 9614: 9611: 9609: 9606: 9604: 9601: 9597: 9594: 9593: 9592: 9589: 9587: 9584: 9582: 9579: 9577: 9573: 9570: 9568: 9565: 9563: 9560: 9558: 9555: 9553: 9550: 9549: 9547: 9543: 9537: 9534: 9532: 9529: 9527: 9526:Recursive set 9524: 9522: 9519: 9517: 9514: 9512: 9509: 9507: 9504: 9500: 9497: 9495: 9492: 9490: 9487: 9485: 9482: 9480: 9477: 9476: 9475: 9472: 9470: 9467: 9465: 9462: 9460: 9457: 9455: 9452: 9450: 9447: 9446: 9444: 9442: 9438: 9432: 9429: 9427: 9424: 9422: 9419: 9417: 9414: 9412: 9409: 9407: 9404: 9402: 9399: 9395: 9392: 9390: 9387: 9385: 9382: 9381: 9380: 9377: 9375: 9372: 9370: 9367: 9365: 9362: 9360: 9357: 9355: 9352: 9348: 9345: 9344: 9343: 9340: 9336: 9335:of arithmetic 9333: 9332: 9331: 9328: 9324: 9321: 9319: 9316: 9314: 9311: 9309: 9306: 9304: 9301: 9300: 9299: 9296: 9292: 9289: 9287: 9284: 9283: 9282: 9279: 9278: 9276: 9274: 9270: 9264: 9261: 9259: 9256: 9254: 9251: 9249: 9246: 9243: 9242:from ZFC 9239: 9236: 9234: 9231: 9225: 9222: 9221: 9220: 9217: 9215: 9212: 9210: 9207: 9206: 9205: 9202: 9200: 9197: 9195: 9192: 9190: 9187: 9185: 9182: 9180: 9177: 9175: 9172: 9171: 9169: 9167: 9163: 9153: 9152: 9148: 9147: 9142: 9141:non-Euclidean 9139: 9135: 9132: 9130: 9127: 9125: 9124: 9120: 9119: 9117: 9114: 9113: 9111: 9107: 9103: 9100: 9098: 9095: 9094: 9093: 9089: 9085: 9082: 9081: 9080: 9076: 9072: 9069: 9067: 9064: 9062: 9059: 9057: 9054: 9052: 9049: 9047: 9044: 9043: 9041: 9037: 9036: 9034: 9029: 9023: 9018:Example  9015: 9007: 9002: 9001: 9000: 8997: 8995: 8992: 8988: 8985: 8983: 8980: 8978: 8975: 8973: 8970: 8969: 8968: 8965: 8963: 8960: 8958: 8955: 8953: 8950: 8946: 8943: 8941: 8938: 8937: 8936: 8933: 8929: 8926: 8924: 8921: 8919: 8916: 8914: 8911: 8910: 8909: 8906: 8904: 8901: 8897: 8894: 8892: 8889: 8887: 8884: 8883: 8882: 8879: 8875: 8872: 8870: 8867: 8865: 8862: 8860: 8857: 8855: 8852: 8850: 8847: 8846: 8845: 8842: 8840: 8837: 8835: 8832: 8830: 8827: 8823: 8820: 8818: 8815: 8813: 8810: 8808: 8805: 8804: 8803: 8800: 8798: 8795: 8793: 8790: 8788: 8785: 8781: 8778: 8776: 8775:by definition 8773: 8772: 8771: 8768: 8764: 8761: 8760: 8759: 8756: 8754: 8751: 8749: 8746: 8744: 8741: 8739: 8736: 8735: 8732: 8729: 8727: 8723: 8718: 8712: 8708: 8698: 8695: 8693: 8690: 8688: 8685: 8683: 8680: 8678: 8675: 8673: 8670: 8668: 8665: 8663: 8662:Kripke–Platek 8660: 8658: 8655: 8651: 8648: 8646: 8643: 8642: 8641: 8638: 8637: 8635: 8631: 8623: 8620: 8619: 8618: 8615: 8613: 8610: 8606: 8603: 8602: 8601: 8598: 8596: 8593: 8591: 8588: 8586: 8583: 8581: 8578: 8575: 8571: 8567: 8564: 8560: 8557: 8555: 8552: 8550: 8547: 8546: 8545: 8541: 8538: 8537: 8535: 8533: 8529: 8525: 8517: 8514: 8512: 8509: 8507: 8506:constructible 8504: 8503: 8502: 8499: 8497: 8494: 8492: 8489: 8487: 8484: 8482: 8479: 8477: 8474: 8472: 8469: 8467: 8464: 8462: 8459: 8457: 8454: 8452: 8449: 8447: 8444: 8442: 8439: 8438: 8436: 8434: 8429: 8421: 8418: 8416: 8413: 8411: 8408: 8406: 8403: 8401: 8398: 8396: 8393: 8392: 8390: 8386: 8383: 8381: 8378: 8377: 8376: 8373: 8371: 8368: 8366: 8363: 8361: 8358: 8356: 8352: 8348: 8346: 8343: 8339: 8336: 8335: 8334: 8331: 8330: 8327: 8324: 8322: 8318: 8308: 8305: 8303: 8300: 8298: 8295: 8293: 8290: 8288: 8285: 8283: 8280: 8276: 8273: 8272: 8271: 8268: 8264: 8259: 8258: 8257: 8254: 8253: 8251: 8249: 8245: 8237: 8234: 8232: 8229: 8227: 8224: 8223: 8222: 8219: 8217: 8214: 8212: 8209: 8207: 8204: 8202: 8199: 8197: 8194: 8192: 8189: 8188: 8186: 8184: 8183:Propositional 8180: 8174: 8171: 8169: 8166: 8164: 8161: 8159: 8156: 8154: 8151: 8149: 8146: 8142: 8139: 8138: 8137: 8134: 8132: 8129: 8127: 8124: 8122: 8119: 8117: 8114: 8112: 8111:Logical truth 8109: 8107: 8104: 8103: 8101: 8099: 8095: 8092: 8090: 8086: 8080: 8077: 8075: 8072: 8070: 8067: 8065: 8062: 8060: 8057: 8055: 8051: 8047: 8043: 8041: 8038: 8036: 8033: 8031: 8027: 8024: 8023: 8021: 8019: 8013: 8008: 8002: 7999: 7997: 7994: 7992: 7989: 7987: 7984: 7982: 7979: 7977: 7974: 7972: 7969: 7967: 7964: 7962: 7959: 7957: 7954: 7952: 7949: 7947: 7944: 7940: 7937: 7936: 7935: 7932: 7931: 7929: 7925: 7921: 7914: 7909: 7907: 7902: 7900: 7895: 7894: 7891: 7879: 7878:Ernst Zermelo 7876: 7874: 7871: 7869: 7866: 7864: 7863:Willard Quine 7861: 7859: 7856: 7854: 7851: 7849: 7846: 7844: 7841: 7839: 7836: 7834: 7831: 7829: 7826: 7824: 7821: 7820: 7818: 7816: 7815:Set theorists 7812: 7806: 7803: 7801: 7798: 7796: 7793: 7792: 7790: 7784: 7782: 7779: 7778: 7775: 7767: 7764: 7762: 7761:Kripke–Platek 7759: 7755: 7752: 7751: 7750: 7747: 7746: 7745: 7742: 7738: 7735: 7734: 7733: 7732: 7728: 7724: 7721: 7720: 7719: 7716: 7715: 7712: 7709: 7707: 7704: 7702: 7699: 7697: 7694: 7693: 7691: 7687: 7681: 7678: 7676: 7673: 7671: 7668: 7666: 7664: 7659: 7657: 7654: 7652: 7649: 7646: 7642: 7639: 7637: 7634: 7630: 7627: 7625: 7622: 7620: 7617: 7616: 7615: 7612: 7609: 7605: 7602: 7600: 7597: 7595: 7592: 7590: 7587: 7586: 7584: 7581: 7577: 7571: 7568: 7566: 7563: 7561: 7558: 7556: 7553: 7551: 7548: 7546: 7543: 7541: 7538: 7534: 7531: 7529: 7526: 7525: 7524: 7521: 7519: 7516: 7514: 7511: 7509: 7506: 7504: 7501: 7498: 7494: 7491: 7489: 7486: 7484: 7481: 7480: 7478: 7472: 7469: 7468: 7465: 7459: 7456: 7454: 7451: 7449: 7446: 7444: 7441: 7439: 7436: 7434: 7431: 7429: 7426: 7423: 7420: 7418: 7415: 7414: 7412: 7410: 7406: 7398: 7397:specification 7395: 7393: 7390: 7389: 7388: 7385: 7384: 7381: 7378: 7376: 7373: 7371: 7368: 7366: 7363: 7361: 7358: 7356: 7353: 7351: 7348: 7346: 7343: 7339: 7336: 7335: 7334: 7331: 7329: 7326: 7322: 7319: 7317: 7314: 7312: 7309: 7308: 7307: 7304: 7302: 7299: 7298: 7296: 7294: 7290: 7285: 7275: 7272: 7271: 7269: 7265: 7261: 7254: 7249: 7247: 7242: 7240: 7235: 7234: 7231: 7219: 7216: 7214: 7211: 7209: 7206: 7204: 7201: 7199: 7196: 7194: 7191: 7189: 7186: 7184: 7181: 7179: 7176: 7174: 7171: 7169: 7166: 7164: 7161: 7157: 7154: 7153: 7152: 7149: 7147: 7144: 7142: 7139: 7137: 7134: 7132: 7131: 7127: 7125: 7122: 7121: 7118: 7114: 7110: 7103: 7098: 7096: 7091: 7089: 7084: 7083: 7080: 7071: 7070: 7065: 7062: 7057: 7053: 7049: 7048: 7043: 7039: 7038: 7029: 7027:3-540-44085-2 7023: 7019: 7015: 7011: 7008: 7004: 7000: 6999:0-387-90092-6 6996: 6992: 6988: 6987: 6982: 6979: 6978: 6970: 6964: 6959: 6958: 6949: 6942: 6936: 6929: 6923: 6920:(in German), 6919: 6915: 6908: 6902:15 pp. 11−23. 6901: 6897: 6893: 6889: 6883: 6875: 6869: 6865: 6860: 6859: 6850: 6848: 6839: 6833: 6829: 6822: 6820: 6808: 6807: 6799: 6797: 6788: 6782: 6778: 6774: 6767: 6765: 6763: 6761: 6756: 6746: 6743: 6741: 6738: 6736: 6733: 6732: 6726: 6712: 6706: 6686: 6680: 6677: 6671: 6668: 6665: 6659: 6639: 6633: 6613: 6607: 6604: 6601: 6598: 6595: 6575: 6555: 6549: 6529: 6523: 6520: 6517: 6514: 6511: 6467: 6447: 6444: 6441: 6438: 6435: 6415: 6409: 6406: 6403: 6383: 6377: 6374: 6371: 6327: 6283: 6251: 6247: 6243: 6234: 6232: 6227: 6226:Ernst Zermelo 6223: 6221: 6217: 6213: 6209: 6205: 6201: 6197: 6193: 6189: 6185: 6181: 6177: 6173: 6172: 6167: 6163: 6161: 6157: 6153: 6149: 6145: 6141: 6137: 6133: 6129: 6125: 6121: 6117: 6107: 6105: 6104:Alonzo Church 6100: 6085: 6080: 6077: 6074: 6071: 6068: 6063: 6059: 6056: 6048: 6044: 6025: 6017: 6013: 6009: 6004: 6000: 5996: 5993: 5990: 5985: 5981: 5967: 5963: 5959: 5954: 5950: 5942: 5941: 5940: 5937: 5933: 5929: 5925: 5921: 5916: 5912: 5908: 5904: 5885: 5880: 5876: 5872: 5867: 5863: 5852: 5848: 5844: 5839: 5835: 5827: 5826: 5825: 5822: 5818: 5814: 5795: 5791: 5786: 5783: 5780: 5777: 5774: 5771: 5768: 5763: 5759: 5754: 5750: 5742: 5741: 5740: 5738: 5734: 5730: 5726: 5721: 5702: 5694: 5683: 5648: 5625: 5595: 5570: 5562: 5551: 5516: 5509: 5508:universal set 5505: 5501: 5499: 5489: 5465: 5426: 5365: 5362:contains all 5304: 5265: 5204: 5200: 5197:Through this 5195: 5111: 5091: 5071: 5062: 5003: 4987: 4978: 4964: 4944: 4924: 4904: 4884: 4864: 4844: 4824: 4804: 4784: 4764: 4744: 4702: 4698: 4682: 4675:we seek. Let 4674: 4673:contradiction 4669: 4667: 4663: 4659: 4655: 4636: 4613: 4607: 4602: 4597: 4587: 4584: 4581: 4578: 4575: 4562: 4552: 4549: 4546: 4543: 4540: 4527: 4517: 4514: 4511: 4508: 4505: 4492: 4482: 4479: 4476: 4463: 4457: 4443: 4442: 4441: 4325: 4285: 4271: 4264: 4240: 4237: 4234: 4231: 4228: 4222: 4216: 4213: 4210: 4207: 4204: 4201: 4198: 4116: 4110: 4107: 4101: 4098: 4095: 4092: 4089: 4086: 4083: 4077: 4071: 4068: 4065: 4062: 4059: 4053: 4047: 4044: 4041: 4035: 4029: 4023: 4017: 4014: 4011: 4008: 4005: 3999: 3993: 3990: 3987: 3981: 3972: 3947: 3946: 3945: 3874: 3870: 3845:Suppose that 3843: 3841: 3838:, the set of 3822: 3819: 3816: 3813: 3810: 3807: 3804: 3798: 3790: 3787: 3779: 3775: 3759: 3747: 3741: 3739: 3735: 3731: 3727: 3722: 3708: 3688: 3680: 3664: 3656: 3637: 3631: 3628: 3625: 3605: 3585: 3565: 3562: 3559: 3536: 3530: 3527: 3524: 3504: 3484: 3481: 3478: 3458: 3438: 3413: 3409: 3402: 3399: 3391: 3387: 3380: 3360: 3340: 3332: 3316: 3308: 3292: 3269: 3266: 3261: 3257: 3253: 3248: 3244: 3237: 3234: 3214: 3206: 3203:", this is a 3187: 3181: 3178: 3175: 3155: 3146: 3132: 3112: 3092: 3072: 3052: 3032: 3012: 2992: 2972: 2952: 2932: 2924: 2908: 2888: 2868: 2859: 2839: 2823: 2820: 2817: 2811: 2805: 2802: 2782: 2759: 2736: 2716: 2707: 2693: 2673: 2653: 2633: 2613: 2593: 2590: 2584: 2578: 2558: 2555: 2552: 2544: 2521: 2513: 2510: 2504: 2498: 2484: 2478: 2475: 2472: 2465: 2460: 2457: 2454: 2447: 2439: 2425: 2419: 2416: 2413: 2406: 2401: 2398: 2395: 2384: 2383: 2382: 2380: 2379:contradiction 2364: 2361: 2355: 2349: 2329: 2326: 2323: 2314: 2300: 2280: 2277: 2274: 2251: 2245: 2242: 2239: 2219: 2212:cannot equal 2196: 2190: 2167: 2161: 2158: 2155: 2135: 2132: 2129: 2106: 2100: 2097: 2094: 2074: 2067:cannot equal 2051: 2045: 2022: 2016: 2013: 2010: 1987: 1981: 1978: 1975: 1952: 1946: 1943: 1940: 1920: 1917: 1914: 1894: 1886: 1870: 1850: 1827: 1821: 1801: 1781: 1758: 1752: 1749: 1746: 1726: 1723: 1720: 1700: 1697: 1694: 1671: 1662: 1656: 1653: 1650: 1647: 1644: 1641: 1638: 1632: 1629: 1622: 1621: 1620: 1606: 1598: 1582: 1559: 1553: 1533: 1530: 1527: 1504: 1498: 1478: 1458: 1438: 1418: 1398: 1377: 1356: 1334: 1313: 1305: 1301: 1285: 1265: 1242: 1236: 1233: 1230: 1224: 1218: 1215: 1205: 1185: 1169: 1166: 1163: 1157: 1151: 1148: 1123: 1117: 1111: 1105: 1082: 1066: 1063: 1060: 1037: 1007: 999: 993: 977: 955: 952: 946: 940: 920: 911: 901: 882: 876: 873: 870: 862: 859: 856: 830: 824: 821: 818: 810: 807: 804: 795: 788: 773: 766: 748: 745: 739: 733: 713: 710: 707: 685: 663: 660: 657: 634: 621: 618: 610: 588: 582: 579: 576: 573: 570: 567: 564: 558: 555: 542: 528: 502: 486: 483: 480: 474: 468: 465: 457: 438: 422: 419: 416: 393: 363: 343: 327: 319: 317: 313: 309: 304: 303:for details. 302: 298: 294: 290: 285: 283: 267: 264: 259: 255: 232: 228: 207: 199: 195: 191: 186: 172: 164: 148: 145: 137: 134:known as the 121: 118: 110: 94: 87: 83: 79: 70: 66: 62: 60: 49: 45: 41: 37: 33: 28: 22: 9682:Georg Cantor 9628: 9426:Ultraproduct 9273:Model theory 9238:Independence 9174:Formal proof 9166:Proof theory 9149: 9122: 9079:real numbers 9051:second-order 8962:Substitution 8839:Metalanguage 8780:conservative 8753:Axiom schema 8697:Constructive 8667:Morse–Kelley 8633:Set theories 8612:Aleph number 8605:inaccessible 8511:Grothendieck 8395:intersection 8282:Higher-order 8270:Second-order 8216:Truth tables 8173:Venn diagram 8045: 7956:Formal proof 7828:Georg Cantor 7823:Paul Bernays 7754:Morse–Kelley 7729: 7710: 7662: 7661:Subset  7608:hereditarily 7570:Venn diagram 7528:ordered pair 7443:Intersection 7387:Axiom schema 7208:Independence 7183:Decidability 7178:Completeness 7128: 7123: 7067: 7045: 7017: 7014:Jech, Thomas 6984: 6981:Halmos, Paul 6956: 6948: 6935: 6927: 6921: 6917: 6907: 6899: 6887: 6882: 6857: 6827: 6805: 6772: 6240: 6224: 6219: 6215: 6211: 6207: 6203: 6199: 6195: 6191: 6187: 6183: 6179: 6169: 6164: 6159: 6155: 6151: 6147: 6143: 6139: 6135: 6131: 6127: 6113: 6101: 6041:Had we used 6040: 5935: 5931: 5919: 5914: 5910: 5900: 5820: 5816: 5812: 5810: 5736: 5732: 5724: 5722: 5661:, therefore 5588:for any set 5502: 5495: 5196: 5063: 4979: 4696: 4670: 4665: 4657: 4651: 4286: 4131: 3944:looks like: 3869:equinumerous 3844: 3751: 3745: 3723: 3307:linear order 3147: 2945:must map to 2860: 2708: 2540: 2315: 1686: 1207: 786: 764: 548: 329: 325: 308:Georg Cantor 305: 293:real numbers 286: 187: 81: 75: 56: 39: 35: 31: 9536:Type theory 9484:undecidable 9416:Truth value 9303:equivalence 8982:non-logical 8595:Enumeration 8585:Isomorphism 8532:cardinality 8516:Von Neumann 8481:Ultrafilter 8446:Uncountable 8380:equivalence 8297:Quantifiers 8287:Fixed-point 8256:First-order 8136:Consistency 8121:Proposition 8098:Traditional 8069:Lindström's 8059:Compactness 8001:Type theory 7946:Cardinality 7853:Thomas Jech 7696:Alternative 7675:Uncountable 7629:Ultrafilter 7488:Cardinality 7392:replacement 7333:Determinacy 7198:Metatheorem 7156:of geometry 7141:Consistency 5733:Russell set 5464:cardinality 5425:cardinality 5303:cardinality 5264:cardinality 5203:cardinality 4977:can exist. 4666:non-selfish 3451:and column 2985:can map to 970:Therefore, 763:From   194:enumeration 190:finite sets 163:cardinality 9667:Set theory 9651:Categories 9347:elementary 9040:arithmetic 8908:Quantifier 8886:functional 8758:Expression 8476:Transitive 8420:identities 8405:complement 8338:hereditary 8321:Set theory 7848:Kurt Gödel 7833:Paul Cohen 7670:Transitive 7438:Identities 7422:Complement 7409:Operations 7370:Regularity 7338:projective 7301:Adjunction 7260:Set theory 7018:Set Theory 6926:, also in 6751:References 5388:inside of 5364:singletons 4897:is not in 3578:. The set 2571:such that 2342:such that 1774:. For all 1098:such that 898: via 726:such that 456:surjective 78:set theory 9618:Supertask 9521:Recursion 9479:decidable 9313:saturated 9291:of models 9214:deductive 9209:axiomatic 9129:Hilbert's 9116:Euclidean 9097:canonical 9020:axiomatic 8952:Signature 8881:Predicate 8770:Extension 8692:Ackermann 8617:Operation 8496:Universal 8486:Recursive 8461:Singleton 8456:Inhabited 8441:Countable 8431:Types of 8415:power set 8385:partition 8302:Predicate 8248:Predicate 8163:Syllogism 8153:Soundness 8126:Inference 8116:Tautology 8018:paradoxes 7781:Paradoxes 7701:Axiomatic 7680:Universal 7656:Singleton 7651:Recursive 7594:Countable 7589:Amorphous 7448:Power set 7365:Power set 7316:dependent 7311:countable 7173:Soundness 7109:Metalogic 7069:MathWorld 7052:EMS Press 6710:→ 6684:→ 6666:− 6637:→ 6611:→ 6605:× 6553:→ 6527:→ 6521:× 6439:∘ 6436:α 6413:→ 6381:→ 6372:α 6010:∉ 5997:∧ 5991:∈ 5974:⟺ 5960:∈ 5873:∉ 5859:⟺ 5845:∈ 5772:∈ 5727:with the 5695:≤ 5002:bijection 4701:power set 4608:⋮ 4603:⋮ 4598:⋮ 4568:⟷ 4533:⟷ 4498:⟷ 4469:⟷ 4272:∅ 4263:empty set 4241:∈ 4217:… 4111:… 4102:… 3979:∅ 3873:power set 3871:with its 3823:… 3629:∈ 3563:∈ 3552:for each 3528:∈ 3482:∈ 3331:power set 3329:from the 3270:… 3179:∈ 2824:⁡ 2806:⁡ 2585:ξ 2556:∈ 2553:ξ 2505:ξ 2485:ξ 2476:∈ 2473:ξ 2469:⟺ 2458:∈ 2455:ξ 2426:ξ 2417:∉ 2414:ξ 2410:⟺ 2399:∈ 2396:ξ 2356:ξ 2327:∈ 2324:ξ 2278:∈ 2243:∉ 2159:∉ 2133:∉ 2098:∈ 2014:∈ 1979:∉ 1944:∈ 1918:∈ 1794:the sets 1750:∉ 1724:∈ 1698:∈ 1648:∣ 1642:∈ 1531:∈ 1237:⁡ 1219:⁡ 1170:⁡ 1152:⁡ 1070:→ 947:ξ 921:φ 918:¬ 915:⇔ 912:φ 883:ξ 874:∉ 871:ξ 867:⟺ 860:∈ 857:ξ 822:∉ 815:⟺ 808:∈ 740:ξ 711:∈ 708:ξ 661:⊆ 622:∈ 580:∉ 574:∣ 568:∈ 487:⁡ 469:⁡ 426:→ 198:empty set 185:itself. 136:power set 48:inclusion 9603:Logicism 9596:timeline 9572:Concrete 9431:Validity 9401:T-schema 9394:Kripke's 9389:Tarski's 9384:semantic 9374:Strength 9323:submodel 9318:spectrum 9286:function 9134:Tarski's 9123:Elements 9110:geometry 9066:Robinson 8987:variable 8972:function 8945:spectrum 8935:Sentence 8891:variable 8834:Language 8787:Relation 8748:Automata 8738:Alphabet 8722:language 8576:-jection 8554:codomain 8540:Function 8501:Universe 8471:Infinite 8375:Relation 8158:Validity 8148:Argument 8046:theorem, 7785:Problems 7689:Theories 7665:Superset 7641:Infinite 7470:Concepts 7350:Infinity 7267:Overview 7016:(2002), 6729:See also 6246:category 6078:∉ 5784:∉ 5327:because 5004:between 3738:Isabelle 3105:maps to 2686:, i.e., 2232:because 2087:because 1654:∉ 1520:for any 996:We know 933:, since 650:because 409:. Then 297:integers 289:infinite 280:for all 9545:Related 9342:Diagram 9240: ( 9219:Hilbert 9204:Systems 9199:Theorem 9077:of the 9022:systems 8802:Formula 8797:Grammar 8713: ( 8657:General 8370:Forcing 8355:Element 8275:Monadic 8050:paradox 7991:Theorem 7927:General 7723:General 7718:Zermelo 7624:subbase 7606: ( 7545:Forcing 7523:Element 7495: ( 7473:Methods 7360:Pairing 7054:, 2001 6924:: 75–78 6110:History 6045:(as in 5907:Zermelo 4837:, then 4662:subsets 4658:selfish 4654:subsets 4324:element 1933:either 1302:but no 765:for all 678:Assume 454:is not 109:subsets 44:ordered 9308:finite 9071:Skolem 9024:  8999:Theory 8967:Symbol 8957:String 8940:atomic 8817:ground 8812:closed 8807:atomic 8763:ground 8726:syntax 8622:binary 8549:domain 8466:Finite 8231:finite 8089:Logics 8048:  7996:Theory 7614:Filter 7604:Finite 7540:Family 7483:Almost 7321:global 7306:Choice 7293:Axioms 7024:  7005:  6997:  6965:  6894:  6870:  6834:  6783:  4817:is in 2921:to be 2901:. For 1887:under 1885:images 1883:whose 799:  611:, and 9298:Model 9046:Peano 8903:Proof 8743:Arity 8672:Naive 8559:image 8491:Fuzzy 8451:Empty 8400:union 8345:Class 7986:Model 7976:Lemma 7934:Axiom 7706:Naive 7636:Fuzzy 7599:Empty 7582:types 7533:tuple 7503:Class 7497:large 7458:Union 7375:Union 6866:–87. 6810:(PDF) 6248:with 6120:reals 6047:Frege 4877:. If 3744:When 3734:Otter 3227:from 2795:that 2183:then 2038:then 2003:. If 1306:from 1000:from 546:Proof 322:Proof 165:than 9421:Type 9224:list 9028:list 9005:list 8994:Term 8928:rank 8822:open 8716:list 8528:Maps 8433:sets 8292:Free 8262:list 8012:list 7939:list 7619:base 7111:and 7022:ISBN 7003:ISBN 6995:ISBN 6963:ISBN 6892:ISBN 6868:ISBN 6832:ISBN 6781:ISBN 5563:> 5227:and 5026:and 2923:onto 2821:card 2818:< 2803:card 2646:and 1814:and 1278:and 1234:card 1231:< 1216:card 1204:. ∎ 1167:card 1164:< 1149:card 484:card 481:< 466:card 336:Let 265:> 188:For 9108:of 9090:of 9038:of 8570:Sur 8544:Map 8351:Ur- 8333:Set 7580:Set 6480:of 5928:ZFC 5466:of 5427:of 5305:of 5266:of 5205:of 4697:all 4326:of 3867:is 3772:is 3333:of 1968:or 1599:of 1370:to 1327:to 1020:to 138:of 111:of 86:set 46:by 9653:: 9494:NP 9118:: 9112:: 9042:: 8719:), 8574:Bi 8566:In 7066:. 7050:, 7044:, 6983:, 6916:, 6864:86 6846:^ 6818:^ 6795:^ 6775:. 6759:^ 6725:. 6233:. 6162:. 6154:)( 5739:: 5720:. 5500:. 5194:. 5061:. 4284:. 3842:. 3776:. 3721:. 2858:. 2381:: 2313:. 1713:, 1619:: 1139:. 994:. 968:. 902:. 787:in 761:. 676:. 541:. 284:. 80:, 38:, 34:, 9574:/ 9489:P 9244:) 9030:) 9026:( 8923:∀ 8918:! 8913:∃ 8874:= 8869:↔ 8864:→ 8859:∧ 8854:√ 8849:ÂŹ 8572:/ 8568:/ 8542:/ 8353:) 8349:( 8236:∞ 8226:3 8014:) 7912:e 7905:t 7898:v 7663:· 7647:) 7643:( 7610:) 7499:) 7252:e 7245:t 7238:v 7101:e 7094:t 7087:v 7072:. 6971:. 6922:1 6876:. 6840:. 6789:. 6713:Y 6707:T 6687:Y 6681:T 6678:: 6675:) 6672:x 6669:, 6663:( 6660:f 6640:Y 6634:T 6614:Y 6608:T 6602:T 6599:: 6596:f 6576:T 6556:Y 6550:T 6530:Y 6524:T 6518:T 6515:: 6512:f 6490:C 6468:T 6448:y 6445:= 6442:y 6416:Y 6410:1 6407:: 6404:y 6384:Y 6378:Y 6375:: 6350:C 6328:Y 6306:C 6284:1 6262:C 6220:x 6216:x 6212:x 6208:x 6204:x 6200:x 6196:x 6192:x 6190:( 6188:x 6184:x 6180:x 6160:f 6156:x 6152:x 6150:( 6148:f 6144:x 6142:( 6140:G 6136:X 6132:X 6128:f 6086:} 6081:x 6075:x 6072:: 6069:x 6064:{ 6060:= 6057:R 6026:. 6023:) 6018:U 6014:R 6005:U 6001:R 5994:U 5986:U 5982:R 5978:( 5968:U 5964:R 5955:U 5951:R 5936:A 5932:R 5920:U 5918:∈ 5915:U 5911:R 5886:. 5881:U 5877:R 5868:U 5864:R 5853:U 5849:R 5840:U 5836:R 5821:U 5817:R 5813:U 5796:. 5792:} 5787:x 5781:x 5778:: 5775:A 5769:x 5764:{ 5760:= 5755:A 5751:R 5737:A 5725:f 5707:| 5703:V 5699:| 5691:| 5687:) 5684:V 5681:( 5676:P 5670:| 5649:V 5629:) 5626:V 5623:( 5618:P 5596:X 5575:| 5571:X 5567:| 5559:| 5555:) 5552:X 5549:( 5544:P 5538:| 5517:V 5475:N 5450:) 5446:N 5442:( 5437:P 5411:) 5407:N 5403:( 5398:P 5375:N 5350:) 5346:N 5342:( 5337:P 5314:N 5289:) 5285:N 5281:( 5276:P 5250:) 5246:N 5242:( 5237:P 5214:N 5182:) 5178:N 5174:( 5169:P 5147:) 5143:N 5139:( 5134:P 5112:x 5092:x 5072:B 5049:) 5045:N 5041:( 5036:P 5013:N 4988:B 4965:B 4945:b 4925:B 4905:B 4885:b 4865:B 4845:b 4825:B 4805:b 4785:b 4765:B 4745:B 4725:) 4721:N 4717:( 4712:P 4683:B 4637:. 4634:) 4630:N 4626:( 4621:P 4614:} 4591:} 4588:5 4585:, 4582:3 4579:, 4576:1 4573:{ 4563:4 4556:} 4553:6 4550:, 4547:5 4544:, 4541:4 4538:{ 4528:3 4521:} 4518:3 4515:, 4512:2 4509:, 4506:1 4503:{ 4493:2 4486:} 4483:5 4480:, 4477:4 4474:{ 4464:1 4458:{ 4452:N 4428:) 4424:N 4420:( 4415:P 4392:N 4371:) 4367:N 4363:( 4358:P 4335:N 4310:) 4306:N 4302:( 4297:P 4249:} 4245:N 4238:k 4235:: 4232:k 4229:2 4226:{ 4223:= 4220:} 4214:, 4211:6 4208:, 4205:4 4202:, 4199:2 4196:{ 4175:N 4154:) 4150:N 4146:( 4141:P 4117:. 4114:} 4108:, 4105:} 4099:, 4096:6 4093:, 4090:4 4087:, 4084:2 4081:{ 4078:, 4075:} 4072:6 4069:, 4066:4 4063:, 4060:3 4057:{ 4054:, 4051:} 4048:5 4045:, 4042:1 4039:{ 4036:, 4033:} 4030:4 4027:{ 4024:, 4021:} 4018:3 4015:, 4012:2 4009:, 4006:1 4003:{ 4000:, 3997:} 3994:2 3991:, 3988:1 3985:{ 3982:, 3976:{ 3973:= 3970:) 3966:N 3962:( 3957:P 3932:) 3928:N 3924:( 3919:P 3897:) 3893:N 3889:( 3884:P 3854:N 3826:} 3820:, 3817:3 3814:, 3811:2 3808:, 3805:1 3802:{ 3799:= 3795:N 3791:= 3788:A 3760:A 3746:A 3709:B 3689:B 3665:B 3641:) 3638:x 3635:( 3632:f 3626:x 3606:D 3586:B 3566:A 3560:x 3540:) 3537:x 3534:( 3531:f 3525:x 3505:D 3485:y 3479:x 3459:y 3439:x 3419:) 3414:2 3410:x 3406:( 3403:f 3400:, 3397:) 3392:1 3388:x 3384:( 3381:f 3361:f 3341:A 3317:y 3293:A 3273:} 3267:, 3262:2 3258:x 3254:, 3249:1 3245:x 3241:{ 3238:= 3235:A 3215:x 3191:) 3188:x 3185:( 3182:f 3176:x 3156:x 3133:f 3113:B 3093:A 3073:B 3053:B 3033:B 3013:B 2993:B 2973:B 2953:B 2933:A 2909:f 2889:A 2869:B 2846:) 2843:) 2840:A 2837:( 2832:P 2827:( 2815:) 2812:A 2809:( 2783:A 2763:} 2760:x 2757:{ 2737:x 2717:A 2694:f 2674:A 2654:f 2634:f 2614:B 2594:B 2591:= 2588:) 2582:( 2579:f 2559:A 2522:. 2518:) 2514:B 2511:= 2508:) 2502:( 2499:f 2488:) 2482:( 2479:f 2461:B 2448:; 2444:) 2440:B 2429:) 2423:( 2420:f 2402:B 2365:B 2362:= 2359:) 2353:( 2350:f 2330:A 2301:B 2281:B 2275:x 2255:) 2252:x 2249:( 2246:f 2240:x 2220:B 2200:) 2197:x 2194:( 2191:f 2171:) 2168:x 2165:( 2162:f 2156:x 2136:B 2130:x 2110:) 2107:x 2104:( 2101:f 2095:x 2075:B 2055:) 2052:x 2049:( 2046:f 2026:) 2023:x 2020:( 2017:f 2011:x 1991:) 1988:x 1985:( 1982:f 1976:x 1956:) 1953:x 1950:( 1947:f 1941:x 1921:A 1915:x 1895:f 1871:A 1851:B 1831:) 1828:x 1825:( 1822:f 1802:B 1782:x 1762:) 1759:x 1756:( 1753:f 1747:x 1727:B 1721:x 1701:A 1695:x 1672:. 1669:} 1666:) 1663:x 1660:( 1657:f 1651:x 1645:A 1639:x 1636:{ 1633:= 1630:B 1607:f 1583:A 1563:) 1560:x 1557:( 1554:f 1534:A 1528:x 1508:) 1505:x 1502:( 1499:f 1479:A 1459:A 1439:A 1419:f 1399:A 1378:Y 1357:X 1347:. 1335:Y 1314:X 1286:Y 1266:X 1246:) 1243:Y 1240:( 1228:) 1225:X 1222:( 1192:) 1189:) 1186:A 1183:( 1178:P 1173:( 1161:) 1158:A 1155:( 1127:} 1124:x 1121:{ 1118:= 1115:) 1112:x 1109:( 1106:g 1086:) 1083:A 1080:( 1075:P 1067:A 1064:: 1061:g 1041:) 1038:A 1035:( 1030:P 1008:A 978:f 956:B 953:= 950:) 944:( 941:f 886:) 880:( 877:f 863:B 837:] 834:) 831:x 828:( 825:f 819:x 811:B 805:x 802:[ 796:A 774:x 749:B 746:= 743:) 737:( 734:f 714:A 686:f 664:A 658:B 638:) 635:A 632:( 627:P 619:B 595:} 592:) 589:x 586:( 583:f 577:x 571:A 565:x 562:{ 559:= 556:B 529:A 509:) 506:) 503:A 500:( 495:P 490:( 478:) 475:A 472:( 442:) 439:A 436:( 431:P 423:A 420:: 417:f 397:) 394:A 391:( 386:P 364:A 344:f 268:n 260:n 256:2 233:n 229:2 208:n 173:A 149:, 146:A 122:, 119:A 95:A 71:. 61:. 50:. 40:z 36:y 32:x 23:.

Index

Cantor's theorem (disambiguation)

ordered
inclusion
special characters
rendering support
question marks, boxes, or other symbols
set theory
set
subsets
power set
cardinality
finite sets
enumeration
empty set
non-negative integers
infinite
real numbers
integers
Cardinality of the continuum
Georg Cantor
philosophy of mathematics
cardinal number
surjective
axiom schema of specification
universal instantiation
reductio ad absurdum
injective maps
injective function
bijective function

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