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Well-founded relation

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5141: 1649: 1636: 1070: 1060: 1030: 1020: 998: 988: 953: 931: 921: 886: 854: 844: 819: 787: 772: 752: 720: 710: 700: 680: 648: 628: 618: 608: 576: 556: 512: 492: 482: 445: 420: 410: 378: 353: 316: 286: 254: 192: 157: 3242:. In the context of the natural numbers, this means that the relation <, which is well-founded, is used instead of the relation ≀, which is not. In some texts, the definition of a well-founded relation is changed from the definition above to include these conventions. 2470: 1380: 1309: 3173:
in the domain of the relation. Every reflexive relation on a nonempty domain has infinite descending chains, because any constant sequence is a descending chain. For example, in the natural numbers with their usual order ≀, we have
2663: 1624: 1238: 1509: 1465: 3178:. To avoid these trivial descending sequences, when working with a partial order ≀, it is common to apply the definition of well foundedness (perhaps implicitly) to the alternate relation < defined such that 1421: 1646:
indicates that the property is not guaranteed in general (it might, or might not, hold). For example, that every equivalence relation is symmetric, but not necessarily antisymmetric, is indicated by
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is an infinite descending chain. This relation fails to be well-founded even though the entire set has a minimum element, namely the empty string.
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There are other interesting special cases of well-founded induction. When the well-founded relation is the usual ordering on the class of all
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implies that set membership is a universal among the extensional well-founded relations: for any set-like well-founded relation
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are all finite, but this does not mean that their lengths are necessarily bounded. Consider the following example: Let
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is a well-founded set, but there are descending chains starting at ω of arbitrary great (finite) length; the chain
5648: 4843: 4587: 3412: 5284: 4148: 3841: 2147: 3582: 5366: 5104: 4806: 4569: 4564: 4389: 3810: 3494: 3311: 3269: 3045:) under the standard ordering, since, for example, the subset of positive rationals (or reals) lacks a minimum. 50: 5685: 5605: 5099: 4882: 4799: 4512: 4443: 4320: 3562: 3360: 2762: 5470: 5399: 5279: 5024: 4850: 4536: 4170: 3769: 20: 5373: 5361: 5324: 5299: 5274: 5228: 5197: 4902: 4897: 4507: 4246: 4175: 3504: 3405: 1158: 5670: 5304: 5294: 5170: 4831: 4421: 3815: 3783: 3474: 2778: 2498: 1542: 5643: 5309: 5121: 5070: 4967: 4465: 4426: 3903: 3548: 2867: 2808:. When the well-founded relation is set membership on the universal class, the technique is known as 2804:. When the well-founded set is a set of recursively-defined data structures, the technique is called 2191: 2036: 2032: 43: 3577: 5861: 5575: 5202: 4962: 4892: 4431: 4283: 4266: 3989: 3469: 2465:{\displaystyle (\forall x\in X)\;\implies P(x)]\quad {\text{implies}}\quad (\forall x\in X)\,P(x).} 2135: 1117: 941: 110: 3078:
be the union of the positive integers with a new element ω that is bigger than any integer. Then
1375:{\displaystyle {\begin{aligned}a\neq {}&b\Rightarrow \\aRb{\text{ or }}&bRa\end{aligned}}} 5823: 5806: 4794: 4771: 4732: 4618: 4559: 4205: 4125: 3969: 3913: 3526: 2790: 5735: 5351: 5084: 4811: 4789: 4756: 4649: 4495: 4480: 4453: 4404: 4288: 4223: 4048: 4014: 4009: 3883: 3714: 3691: 3027: 2984: 2754: 1304:{\displaystyle {\begin{aligned}aRb{\text{ and }}&bRa\\\Rightarrow a={}&b\end{aligned}}} 1087: 80: 5713: 5548: 5408: 5289: 5243: 5207: 5163: 5014: 4867: 4659: 4377: 4113: 4019: 3878: 3863: 3744: 3719: 2801: 2482: 2211: 2131: 1642:
indicates that the column's property is always true the row's term (at the very left), while
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Every class whose elements are sets, with the relation ∈ ("is an element of"). This is the
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A term's definition may require additional properties that are not listed in this table.
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An important reason that well-founded relations are interesting is because a version of
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The set of strings over a finite alphabet with more than one element, under the usual (
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On par with induction, well-founded relations also support construction of objects by
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Well-founded induction is sometimes called Noetherian induction, after
2119: 2112: 596: 1460:{\displaystyle {\begin{aligned}a\vee b\\{\text{exists}}\end{aligned}}} 5835: 5708: 5514: 5126: 5029: 4082: 3999: 3959: 3923: 3859: 3671: 3661: 3634: 3397: 2195: 1850: 1416:{\displaystyle {\begin{aligned}\min S\\{\text{exists}}\end{aligned}}} 19:"Noetherian induction" redirects here. For the use in topology, see 5630: 5497: 5248: 5111: 4909: 4357: 4062: 3656: 3209: 213: 2028:, i.e., that the elements less than any given element form a set. 4707: 3499: 2847: 2825: 5155: 1853: 3286:"Infinite Sequence Property of Strictly Well-Founded Relation" 4251: 3597: 3442: 2820:
Well-founded relations that are not totally ordered include:
3212:≀, it is common to use the relation < defined such that 3015:
Examples of relations that are not well-founded include:
2039:, which can be proved when there is no infinite sequence 3384:, 3rd edition, "Well-founded relations", pages 251–5, 2579: 2325: 1911: 1782: 1756: 1730: 1695: 1671: 1577: 1545: 1518: 1474: 1430: 1389: 1318: 1247: 1191: 1161: 1135: 2712:As an example, consider the well-founded relation 2657: 2464: 2012: 1797: 1768: 1742: 1716: 1677: 1618: 1562: 1530: 1503: 1459: 1415: 1374: 1303: 1232: 1176: 1147: 3264:(2nd, rev. ed.). New York: Springer-Verlag. 2870:over a fixed alphabet, with the order defined by 2035:, a relation is well-founded when it contains no 1905:. In other words, a relation is well founded if: 5853: 1394: 2198:systems, a Noetherian relation is also called 2107:is a well-founded relation. If the order is a 5171: 3413: 3313:Theory of Relations, Volume 145 - 1st Edition 3032:"B" > "AB" > "AAB" > "AAAB" > ... 2020:Some authors include an extra condition that 1659:in the "Antisymmetric" column, respectively. 51: 3345:Elements of mathematics. Commutative algebra 2667:That is, if we want to construct a function 2613: 2103:is called well-founded if the corresponding 3259: 5829:Positive cone of a partially ordered group 5178: 5164: 3605: 3420: 3406: 3117:that is extensional, there exists a class 2405: 2401: 2385: 2381: 2366: 2344: 2205: 2150:, asserts that all sets are well-founded. 1947: 1943: 1930: 58: 44: 3070:, then the descending chains starting at 2628: 2446: 2013:{\displaystyle (\forall S\subseteq X)\;.} 5812:Positive cone of an ordered vector space 3355:Just, Winfried and Weese, Martin (1998) 3309: 2812:. See those articles for more details. 2738:is the graph of the successor function 5854: 3427: 3316:(1st ed.). Elsevier. p. 46. 3208:. More generally, when working with a 5159: 3401: 3003:if and only if there is an edge from 2789:is well-founded is also known as the 3262:Introduction to axiomatic set theory 2765:. If we consider the order relation 1662:All definitions tacitly require the 3049: 1177:{\displaystyle S\neq \varnothing :} 13: 5339:Properties & Types ( 2559:. Then there is a unique function 2505:a function that assigns an object 2431: 2351: 2329: 1984: 1969: 1951: 1915: 14: 5873: 5795:Positive cone of an ordered field 1940: 1168: 5649:Ordered topological vector space 5185: 5139: 3357:Discovering Modern Set Theory. I 3310:Fraisse, R. (15 December 2000). 3260:Zaring W.M., G. Takeuti (1971). 2235:is some property of elements of 2146:, which is one of the axioms of 2134:relation is well-founded on the 1647: 1634: 1563:{\displaystyle {\text{not }}aRa} 1068: 1058: 1028: 1018: 996: 986: 951: 929: 919: 884: 852: 842: 817: 785: 770: 750: 718: 708: 698: 678: 646: 626: 616: 606: 574: 554: 510: 490: 480: 443: 418: 408: 376: 351: 314: 284: 252: 190: 155: 3062:is a well-founded relation and 2427: 2421: 3337: 3303: 3278: 3252: 3144: 2589: 2583: 2456: 2450: 2443: 2428: 2418: 2415: 2409: 2402: 2398: 2395: 2389: 2382: 2367: 2363: 2348: 2345: 2341: 2326: 2224:) is a well-founded relation, 2004: 2001: 1987: 1981: 1966: 1963: 1948: 1944: 1931: 1927: 1912: 1655:in the "Symmetric" column and 1591: 1336: 1281: 1210: 1: 5606:Series-parallel partial order 5100:History of mathematical logic 3361:American Mathematical Society 3245: 3030:) order, since the sequence 1656: 1643: 1053: 1048: 1043: 1038: 1013: 981: 976: 971: 966: 961: 946: 914: 909: 904: 899: 894: 879: 867: 862: 837: 832: 827: 812: 800: 795: 780: 765: 760: 745: 733: 728: 693: 688: 673: 661: 656: 641: 636: 601: 589: 584: 569: 564: 549: 544: 539: 525: 520: 505: 500: 475: 470: 458: 453: 438: 433: 428: 403: 391: 386: 371: 366: 361: 346: 341: 329: 324: 309: 304: 299: 294: 279: 267: 262: 247: 242: 237: 232: 227: 222: 205: 200: 185: 180: 175: 170: 165: 5285:Cantor's isomorphism theorem 5025:Primitive recursive function 2831:, with the order defined by 2190:is also said to satisfy the 21:Noetherian topological space 7: 5325:Szpilrajn extension theorem 5300:Hausdorff maximal principle 5275:Boolean prime ideal theorem 2815: 2520:to each pair of an element 2239:, and we want to show that 2148:Zermelo–Fraenkel set theory 2031:Equivalently, assuming the 1873:; that is, there exists an 10: 5878: 5671:Topological vector lattice 4089:Schröder–Bernstein theorem 3816:Monadic predicate calculus 3475:Foundations of mathematics 3382:Introduction to Set Theory 2800:, the technique is called 2779:course-of-values recursion 2501:well-founded relation and 2265:it suffices to show that: 2037:infinite descending chains 18: 5701: 5629: 5568: 5338: 5267: 5216: 5193: 5135: 5122:Philosophy of mathematics 5071:Automated theorem proving 5053: 4948: 4780: 4673: 4525: 4242: 4218: 4196:Von Neumann–Bernays–Gödel 4141: 4035: 3939: 3837: 3828: 3755: 3690: 3596: 3518: 3435: 2884:is a proper substring of 2214:can be used on them: if ( 2192:ascending chain condition 2088:for every natural number 2033:axiom of dependent choice 5280:Cantor–Bernstein theorem 3107:Mostowski collapse lemma 3037:The set of non-negative 2983:The nodes of any finite 5824:Partially ordered group 5644:Specialization preorder 4772:Self-verifying theories 4593:Tarski's axiomatization 3544:Tarski's undefinability 3539:incompleteness theorems 3258:See Definition 6.21 in 2791:well-ordering principle 2253:holds for all elements 2206:Induction and recursion 16:Type of binary relation 5310:Kruskal's tree theorem 5305:Knaster–Tarski theorem 5295:Dushnik–Miller theorem 5146:Mathematics portal 4757:Proof of impossibility 4405:propositional variable 3715:Propositional calculus 3019:The negative integers 2985:directed acyclic graph 2866:The set of all finite 2755:mathematical induction 2659: 2466: 2014: 1842:or, more generally, a 1799: 1770: 1744: 1718: 1717:{\displaystyle a,b,c,} 1679: 1620: 1564: 1532: 1505: 1461: 1417: 1376: 1305: 1234: 1178: 1149: 5015:Kolmogorov complexity 4968:Computably enumerable 4868:Model complete theory 4660:Principia Mathematica 3720:Propositional formula 3549:Banach–Tarski paradox 2802:transfinite induction 2781:. The statement that 2660: 2483:transfinite recursion 2467: 2212:transfinite induction 2159:converse well-founded 2015: 1883:such that, for every 1800: 1771: 1745: 1719: 1680: 1621: 1565: 1533: 1506: 1462: 1418: 1377: 1306: 1235: 1179: 1150: 1129:Definitions, for all 5802:Ordered vector space 4963:Church–Turing thesis 4950:Computability theory 4159:continuum hypothesis 3677:Square of opposition 3535:Gödel's completeness 3343:Bourbaki, N. (1972) 2987:, with the relation 2806:structural induction 2749:. Then induction on 2686:using the values of 2577: 2563:such that for every 2323: 2194:. In the context of 2163:upwards well-founded 2111:then it is called a 1909: 1893:, one does not have 1798:{\displaystyle aRc.} 1780: 1754: 1728: 1693: 1669: 1664:homogeneous relation 1575: 1543: 1516: 1472: 1428: 1387: 1316: 1245: 1189: 1159: 1133: 875:Strict partial order 150:Equivalence relation 5640:Alexandrov topology 5586:Lexicographic order 5545:Well-quasi-ordering 5117:Mathematical object 5008:P versus NP problem 4973:Computable function 4767:Reverse mathematics 4693:Logical consequence 4570:primitive recursive 4565:elementary function 4338:Free/bound variable 4191:Tarski–Grothendieck 3710:Logical connectives 3640:Logical equivalence 3490:Logical consequence 2978:axiom of regularity 2763:primitive recursion 2757:, and recursion on 2182:is well-founded on 2144:axiom of regularity 1769:{\displaystyle bRc} 1743:{\displaystyle aRb} 1531:{\displaystyle aRa} 1148:{\displaystyle a,b} 534:Well-quasi-ordering 5621:Transitive closure 5581:Converse/Transpose 5290:Dilworth's theorem 4915:Transfer principle 4878:Semantics of logic 4863:Categorical theory 4839:Non-standard model 4353:Logical connective 3480:Information theory 3429:Mathematical logic 2991:defined such that 2775:complete induction 2730:is the set of all 2655: 2462: 2315:must also be true. 2136:transitive closure 2010: 1795: 1766: 1740: 1714: 1675: 1616: 1614: 1560: 1528: 1501: 1499: 1457: 1455: 1413: 1411: 1372: 1370: 1301: 1299: 1230: 1228: 1174: 1145: 1009:Strict total order 5849: 5848: 5807:Partially ordered 5616:Symmetric closure 5601:Reflexive closure 5344: 5153: 5152: 5085:Abstract category 4888:Theories of truth 4698:Rule of inference 4688:Natural deduction 4669: 4668: 4214: 4213: 3919:Cartesian product 3824: 3823: 3730:Many-valued logic 3705:Boolean functions 3588:Russell's paradox 3563:diagonal argument 3460:First-order logic 3347:, Addison-Wesley. 3133:is isomorphic to 3066:is an element of 3021:{−1, −2, −3, ...} 2425: 2273:is an element of 2175:converse relation 1811: 1810: 1678:{\displaystyle R} 1629: 1628: 1601: 1549: 1495: 1451: 1407: 1355: 1264: 942:Strict weak order 128:Total, Semiconnex 5869: 5591:Linear extension 5340: 5320:Mirsky's theorem 5180: 5173: 5166: 5157: 5156: 5144: 5143: 5095:History of logic 5090:Category of sets 4983:Decision problem 4762:Ordinal analysis 4703:Sequent calculus 4601:Boolean algebras 4541: 4540: 4515: 4486:logical/constant 4240: 4239: 4226: 4149:Zermelo–Fraenkel 3900:Set operations: 3835: 3834: 3772: 3603: 3602: 3583:Löwenheim–Skolem 3470:Formal semantics 3422: 3415: 3408: 3399: 3398: 3348: 3341: 3335: 3334: 3332: 3330: 3307: 3301: 3300: 3298: 3296: 3282: 3276: 3275: 3256: 3241: 3231: 3221: 3207: 3197: 3187: 3177: 3172: 3169:holds for every 3168: 3152: 3140: 3132: 3120: 3116: 3112: 3101: 3097: 3093: 3081: 3077: 3073: 3069: 3065: 3061: 3050:Other properties 3039:rational numbers 3033: 3022: 3010: 3006: 3002: 2990: 2972: 2956: 2940: 2900: 2887: 2883: 2879: 2862: 2852: 2846: 2840: 2830: 2788: 2772: 2760: 2752: 2748: 2737: 2729: 2723: 2708: 2696: 2685: 2675:, we may define 2674: 2670: 2664: 2662: 2661: 2656: 2651: 2647: 2646: 2645: 2644: 2640: 2636: 2572: 2562: 2558: 2554: 2533: 2529: 2519: 2504: 2496: 2471: 2469: 2468: 2463: 2426: 2423: 2377: 2314: 2303: 2291: 2288:is true for all 2287: 2276: 2272: 2260: 2256: 2252: 2238: 2234: 2223: 2189: 2185: 2181: 2172: 2156: 2141: 2128:well-founded set 2125: 2091: 2087: 2066: 2062: 2023: 2019: 2017: 2016: 2011: 1997: 1904: 1892: 1882: 1872: 1869:with respect to 1864: 1848: 1825: 1804: 1802: 1801: 1796: 1775: 1773: 1772: 1767: 1749: 1747: 1746: 1741: 1723: 1721: 1720: 1715: 1684: 1682: 1681: 1676: 1658: 1654: 1651: 1650: 1645: 1641: 1638: 1637: 1625: 1623: 1622: 1617: 1615: 1602: 1599: 1569: 1567: 1566: 1561: 1550: 1547: 1537: 1535: 1534: 1529: 1510: 1508: 1507: 1502: 1500: 1496: 1493: 1466: 1464: 1463: 1458: 1456: 1452: 1449: 1422: 1420: 1419: 1414: 1412: 1408: 1405: 1381: 1379: 1378: 1373: 1371: 1356: 1353: 1330: 1310: 1308: 1307: 1302: 1300: 1291: 1265: 1262: 1239: 1237: 1236: 1231: 1229: 1214: 1195: 1183: 1181: 1180: 1175: 1154: 1152: 1151: 1146: 1075: 1072: 1071: 1065: 1062: 1061: 1055: 1050: 1045: 1040: 1035: 1032: 1031: 1025: 1022: 1021: 1015: 1003: 1000: 999: 993: 990: 989: 983: 978: 973: 968: 963: 958: 955: 954: 948: 936: 933: 932: 926: 923: 922: 916: 911: 906: 901: 896: 891: 888: 887: 881: 869: 864: 859: 856: 855: 849: 846: 845: 839: 834: 829: 824: 821: 820: 814: 808:Meet-semilattice 802: 797: 792: 789: 788: 782: 777: 774: 773: 767: 762: 757: 754: 753: 747: 741:Join-semilattice 735: 730: 725: 722: 721: 715: 712: 711: 705: 702: 701: 695: 690: 685: 682: 681: 675: 663: 658: 653: 650: 649: 643: 638: 633: 630: 629: 623: 620: 619: 613: 610: 609: 603: 591: 586: 581: 578: 577: 571: 566: 561: 558: 557: 551: 546: 541: 536: 527: 522: 517: 514: 513: 507: 502: 497: 494: 493: 487: 484: 483: 477: 472: 460: 455: 450: 447: 446: 440: 435: 430: 425: 422: 421: 415: 412: 411: 405: 393: 388: 383: 380: 379: 373: 368: 363: 358: 355: 354: 348: 343: 331: 326: 321: 318: 317: 311: 306: 301: 296: 291: 288: 287: 281: 269: 264: 259: 256: 255: 249: 244: 239: 234: 229: 224: 219: 217: 207: 202: 197: 194: 193: 187: 182: 177: 172: 167: 162: 159: 158: 152: 70: 69: 60: 53: 46: 39: 37:binary relations 28: 27: 5877: 5876: 5872: 5871: 5870: 5868: 5867: 5866: 5862:Wellfoundedness 5852: 5851: 5850: 5845: 5841:Young's lattice 5697: 5625: 5564: 5414:Heyting algebra 5362:Boolean algebra 5334: 5315:Laver's theorem 5263: 5229:Boolean algebra 5224:Binary relation 5212: 5189: 5184: 5154: 5149: 5138: 5131: 5076:Category theory 5066:Algebraic logic 5049: 5020:Lambda calculus 4958:Church encoding 4944: 4920:Truth predicate 4776: 4742:Complete theory 4665: 4534: 4530: 4526: 4521: 4513: 4233: and  4229: 4224: 4210: 4186:New Foundations 4154:axiom of choice 4137: 4099:Gödel numbering 4039: and  4031: 3935: 3820: 3770: 3751: 3700:Boolean algebra 3686: 3650:Equiconsistency 3615:Classical logic 3592: 3573:Halting problem 3561: and  3537: and  3525: and  3524: 3519:Theorems ( 3514: 3431: 3426: 3352: 3351: 3342: 3338: 3328: 3326: 3324: 3308: 3304: 3294: 3292: 3284: 3283: 3279: 3272: 3257: 3253: 3248: 3233: 3223: 3222:if and only if 3213: 3199: 3189: 3188:if and only if 3179: 3176:1 ≄ 1 ≄ 1 ≄ ... 3175: 3170: 3158: 3150: 3147: 3134: 3122: 3118: 3114: 3110: 3099: 3095: 3083: 3079: 3075: 3071: 3067: 3063: 3055: 3052: 3031: 3020: 3008: 3004: 2992: 2988: 2971: 2964: 2958: 2955: 2948: 2942: 2941:if and only if 2938: 2931: 2924: 2917: 2910: 2907:natural numbers 2892: 2885: 2881: 2880:if and only if 2871: 2854: 2850: 2844: 2832: 2828: 2818: 2798:ordinal numbers 2782: 2766: 2758: 2750: 2739: 2735: 2732:natural numbers 2725: 2713: 2698: 2687: 2676: 2672: 2668: 2632: 2621: 2617: 2616: 2612: 2602: 2598: 2578: 2575: 2574: 2564: 2560: 2556: 2538: 2536:initial segment 2531: 2530:and a function 2521: 2506: 2502: 2486: 2422: 2373: 2324: 2321: 2320: 2305: 2293: 2289: 2278: 2274: 2270: 2258: 2254: 2243: 2236: 2225: 2215: 2208: 2187: 2186:. In this case 2183: 2177: 2170: 2154: 2139: 2123: 2089: 2086: 2077: 2068: 2064: 2063:of elements of 2060: 2053: 2046: 2040: 2021: 1993: 1910: 1907: 1906: 1894: 1884: 1874: 1870: 1867:minimal element 1856: 1846: 1823: 1821:binary relation 1813: 1812: 1805: 1781: 1778: 1777: 1755: 1752: 1751: 1729: 1726: 1725: 1694: 1691: 1690: 1670: 1667: 1666: 1660: 1652: 1648: 1639: 1635: 1613: 1612: 1598: 1595: 1594: 1578: 1576: 1573: 1572: 1546: 1544: 1541: 1540: 1517: 1514: 1513: 1498: 1497: 1492: 1489: 1488: 1475: 1473: 1470: 1469: 1454: 1453: 1448: 1445: 1444: 1431: 1429: 1426: 1425: 1410: 1409: 1404: 1401: 1400: 1390: 1388: 1385: 1384: 1369: 1368: 1357: 1352: 1340: 1339: 1331: 1329: 1319: 1317: 1314: 1313: 1298: 1297: 1292: 1290: 1278: 1277: 1266: 1263: and  1261: 1248: 1246: 1243: 1242: 1227: 1226: 1215: 1213: 1207: 1206: 1192: 1190: 1187: 1186: 1160: 1157: 1156: 1134: 1131: 1130: 1073: 1069: 1063: 1059: 1033: 1029: 1023: 1019: 1001: 997: 991: 987: 956: 952: 934: 930: 924: 920: 889: 885: 857: 853: 847: 843: 822: 818: 790: 786: 775: 771: 755: 751: 723: 719: 713: 709: 703: 699: 683: 679: 651: 647: 631: 627: 621: 617: 611: 607: 579: 575: 559: 555: 532: 515: 511: 495: 491: 485: 481: 466:Prewellordering 448: 444: 423: 419: 413: 409: 381: 377: 356: 352: 319: 315: 289: 285: 257: 253: 215: 212: 195: 191: 160: 156: 148: 140: 64: 31: 24: 17: 12: 11: 5: 5875: 5865: 5864: 5847: 5846: 5844: 5843: 5838: 5833: 5832: 5831: 5821: 5820: 5819: 5814: 5809: 5799: 5798: 5797: 5787: 5782: 5781: 5780: 5775: 5768:Order morphism 5765: 5764: 5763: 5753: 5748: 5743: 5738: 5733: 5732: 5731: 5721: 5716: 5711: 5705: 5703: 5699: 5698: 5696: 5695: 5694: 5693: 5688: 5686:Locally convex 5683: 5678: 5668: 5666:Order topology 5663: 5662: 5661: 5659:Order topology 5656: 5646: 5636: 5634: 5627: 5626: 5624: 5623: 5618: 5613: 5608: 5603: 5598: 5593: 5588: 5583: 5578: 5572: 5570: 5566: 5565: 5563: 5562: 5552: 5542: 5537: 5532: 5527: 5522: 5517: 5512: 5507: 5506: 5505: 5495: 5490: 5489: 5488: 5483: 5478: 5473: 5471:Chain-complete 5463: 5458: 5457: 5456: 5451: 5446: 5441: 5436: 5426: 5421: 5416: 5411: 5406: 5396: 5391: 5386: 5381: 5376: 5371: 5370: 5369: 5359: 5354: 5348: 5346: 5336: 5335: 5333: 5332: 5327: 5322: 5317: 5312: 5307: 5302: 5297: 5292: 5287: 5282: 5277: 5271: 5269: 5265: 5264: 5262: 5261: 5256: 5251: 5246: 5241: 5236: 5231: 5226: 5220: 5218: 5214: 5213: 5211: 5210: 5205: 5200: 5194: 5191: 5190: 5183: 5182: 5175: 5168: 5160: 5151: 5150: 5136: 5133: 5132: 5130: 5129: 5124: 5119: 5114: 5109: 5108: 5107: 5097: 5092: 5087: 5078: 5073: 5068: 5063: 5061:Abstract logic 5057: 5055: 5051: 5050: 5048: 5047: 5042: 5040:Turing machine 5037: 5032: 5027: 5022: 5017: 5012: 5011: 5010: 5005: 5000: 4995: 4990: 4980: 4978:Computable set 4975: 4970: 4965: 4960: 4954: 4952: 4946: 4945: 4943: 4942: 4937: 4932: 4927: 4922: 4917: 4912: 4907: 4906: 4905: 4900: 4895: 4885: 4880: 4875: 4873:Satisfiability 4870: 4865: 4860: 4859: 4858: 4848: 4847: 4846: 4836: 4835: 4834: 4829: 4824: 4819: 4814: 4804: 4803: 4802: 4797: 4790:Interpretation 4786: 4784: 4778: 4777: 4775: 4774: 4769: 4764: 4759: 4754: 4744: 4739: 4738: 4737: 4736: 4735: 4725: 4720: 4710: 4705: 4700: 4695: 4690: 4685: 4679: 4677: 4671: 4670: 4667: 4666: 4664: 4663: 4655: 4654: 4653: 4652: 4647: 4646: 4645: 4640: 4635: 4615: 4614: 4613: 4611:minimal axioms 4608: 4597: 4596: 4595: 4584: 4583: 4582: 4577: 4572: 4567: 4562: 4557: 4544: 4542: 4523: 4522: 4520: 4519: 4518: 4517: 4505: 4500: 4499: 4498: 4493: 4488: 4483: 4473: 4468: 4463: 4458: 4457: 4456: 4451: 4441: 4440: 4439: 4434: 4429: 4424: 4414: 4409: 4408: 4407: 4402: 4397: 4387: 4386: 4385: 4380: 4375: 4370: 4365: 4360: 4350: 4345: 4340: 4335: 4334: 4333: 4328: 4323: 4318: 4308: 4303: 4301:Formation rule 4298: 4293: 4292: 4291: 4286: 4276: 4275: 4274: 4264: 4259: 4254: 4249: 4243: 4237: 4220:Formal systems 4216: 4215: 4212: 4211: 4209: 4208: 4203: 4198: 4193: 4188: 4183: 4178: 4173: 4168: 4163: 4162: 4161: 4156: 4145: 4143: 4139: 4138: 4136: 4135: 4134: 4133: 4123: 4118: 4117: 4116: 4109:Large cardinal 4106: 4101: 4096: 4091: 4086: 4072: 4071: 4070: 4065: 4060: 4045: 4043: 4033: 4032: 4030: 4029: 4028: 4027: 4022: 4017: 4007: 4002: 3997: 3992: 3987: 3982: 3977: 3972: 3967: 3962: 3957: 3952: 3946: 3944: 3937: 3936: 3934: 3933: 3932: 3931: 3926: 3921: 3916: 3911: 3906: 3898: 3897: 3896: 3891: 3881: 3876: 3874:Extensionality 3871: 3869:Ordinal number 3866: 3856: 3851: 3850: 3849: 3838: 3832: 3826: 3825: 3822: 3821: 3819: 3818: 3813: 3808: 3803: 3798: 3793: 3788: 3787: 3786: 3776: 3775: 3774: 3761: 3759: 3753: 3752: 3750: 3749: 3748: 3747: 3742: 3737: 3727: 3722: 3717: 3712: 3707: 3702: 3696: 3694: 3688: 3687: 3685: 3684: 3679: 3674: 3669: 3664: 3659: 3654: 3653: 3652: 3642: 3637: 3632: 3627: 3622: 3617: 3611: 3609: 3600: 3594: 3593: 3591: 3590: 3585: 3580: 3575: 3570: 3565: 3553:Cantor's  3551: 3546: 3541: 3531: 3529: 3516: 3515: 3513: 3512: 3507: 3502: 3497: 3492: 3487: 3482: 3477: 3472: 3467: 3462: 3457: 3452: 3451: 3450: 3439: 3437: 3433: 3432: 3425: 3424: 3417: 3410: 3402: 3396: 3395: 3371: 3350: 3349: 3336: 3322: 3302: 3277: 3270: 3250: 3249: 3247: 3244: 3153:is said to be 3146: 3143: 3092:− 2, ..., 2, 1 3051: 3048: 3047: 3046: 3035: 3024: 3013: 3012: 2981: 2974: 2969: 2962: 2953: 2946: 2936: 2929: 2922: 2915: 2889: 2864: 2842:if and only if 2829:{1, 2, 3, ...} 2817: 2814: 2654: 2650: 2643: 2639: 2635: 2631: 2627: 2624: 2620: 2615: 2611: 2608: 2605: 2601: 2597: 2594: 2591: 2588: 2585: 2582: 2461: 2458: 2455: 2452: 2449: 2445: 2442: 2439: 2436: 2433: 2430: 2420: 2417: 2414: 2411: 2408: 2404: 2400: 2397: 2394: 2391: 2388: 2384: 2380: 2376: 2372: 2369: 2365: 2362: 2359: 2356: 2353: 2350: 2347: 2343: 2340: 2337: 2334: 2331: 2328: 2317: 2316: 2263: 2262: 2207: 2204: 2132:set membership 2084: 2072: 2058: 2051: 2044: 2009: 2006: 2003: 2000: 1996: 1992: 1989: 1986: 1983: 1980: 1977: 1974: 1971: 1968: 1965: 1962: 1959: 1956: 1953: 1950: 1946: 1942: 1939: 1936: 1933: 1929: 1926: 1923: 1920: 1917: 1914: 1809: 1808: 1794: 1791: 1788: 1785: 1765: 1762: 1759: 1739: 1736: 1733: 1713: 1710: 1707: 1704: 1701: 1698: 1674: 1631: 1630: 1627: 1626: 1611: 1608: 1605: 1597: 1596: 1593: 1590: 1587: 1584: 1581: 1580: 1570: 1559: 1556: 1553: 1538: 1527: 1524: 1521: 1511: 1491: 1490: 1487: 1484: 1481: 1478: 1477: 1467: 1447: 1446: 1443: 1440: 1437: 1434: 1433: 1423: 1403: 1402: 1399: 1396: 1393: 1392: 1382: 1367: 1364: 1361: 1358: 1354: or  1351: 1348: 1345: 1342: 1341: 1338: 1335: 1332: 1328: 1325: 1322: 1321: 1311: 1296: 1293: 1289: 1286: 1283: 1280: 1279: 1276: 1273: 1270: 1267: 1260: 1257: 1254: 1251: 1250: 1240: 1225: 1222: 1219: 1216: 1212: 1209: 1208: 1205: 1202: 1199: 1196: 1194: 1184: 1173: 1170: 1167: 1164: 1144: 1141: 1138: 1126: 1125: 1120: 1115: 1110: 1105: 1100: 1095: 1090: 1085: 1080: 1077: 1076: 1066: 1056: 1051: 1046: 1041: 1036: 1026: 1016: 1011: 1005: 1004: 994: 984: 979: 974: 969: 964: 959: 949: 944: 938: 937: 927: 917: 912: 907: 902: 897: 892: 882: 877: 871: 870: 865: 860: 850: 840: 835: 830: 825: 815: 810: 804: 803: 798: 793: 783: 778: 768: 763: 758: 748: 743: 737: 736: 731: 726: 716: 706: 696: 691: 686: 676: 671: 665: 664: 659: 654: 644: 639: 634: 624: 614: 604: 599: 593: 592: 587: 582: 572: 567: 562: 552: 547: 542: 537: 529: 528: 523: 518: 508: 503: 498: 488: 478: 473: 468: 462: 461: 456: 451: 441: 436: 431: 426: 416: 406: 401: 395: 394: 389: 384: 374: 369: 364: 359: 349: 344: 339: 337:Total preorder 333: 332: 327: 322: 312: 307: 302: 297: 292: 282: 277: 271: 270: 265: 260: 250: 245: 240: 235: 230: 225: 220: 209: 208: 203: 198: 188: 183: 178: 173: 168: 163: 153: 145: 144: 142: 137: 135: 133: 131: 129: 126: 124: 122: 119: 118: 113: 108: 103: 98: 93: 88: 83: 78: 73: 66: 65: 63: 62: 55: 48: 40: 26: 25: 15: 9: 6: 4: 3: 2: 5874: 5863: 5860: 5859: 5857: 5842: 5839: 5837: 5834: 5830: 5827: 5826: 5825: 5822: 5818: 5815: 5813: 5810: 5808: 5805: 5804: 5803: 5800: 5796: 5793: 5792: 5791: 5790:Ordered field 5788: 5786: 5783: 5779: 5776: 5774: 5771: 5770: 5769: 5766: 5762: 5759: 5758: 5757: 5754: 5752: 5749: 5747: 5746:Hasse diagram 5744: 5742: 5739: 5737: 5734: 5730: 5727: 5726: 5725: 5724:Comparability 5722: 5720: 5717: 5715: 5712: 5710: 5707: 5706: 5704: 5700: 5692: 5689: 5687: 5684: 5682: 5679: 5677: 5674: 5673: 5672: 5669: 5667: 5664: 5660: 5657: 5655: 5652: 5651: 5650: 5647: 5645: 5641: 5638: 5637: 5635: 5632: 5628: 5622: 5619: 5617: 5614: 5612: 5609: 5607: 5604: 5602: 5599: 5597: 5596:Product order 5594: 5592: 5589: 5587: 5584: 5582: 5579: 5577: 5574: 5573: 5571: 5569:Constructions 5567: 5561: 5557: 5553: 5550: 5546: 5543: 5541: 5538: 5536: 5533: 5531: 5528: 5526: 5523: 5521: 5518: 5516: 5513: 5511: 5508: 5504: 5501: 5500: 5499: 5496: 5494: 5491: 5487: 5484: 5482: 5479: 5477: 5474: 5472: 5469: 5468: 5467: 5466:Partial order 5464: 5462: 5459: 5455: 5454:Join and meet 5452: 5450: 5447: 5445: 5442: 5440: 5437: 5435: 5432: 5431: 5430: 5427: 5425: 5422: 5420: 5417: 5415: 5412: 5410: 5407: 5405: 5401: 5397: 5395: 5392: 5390: 5387: 5385: 5382: 5380: 5377: 5375: 5372: 5368: 5365: 5364: 5363: 5360: 5358: 5355: 5353: 5352:Antisymmetric 5350: 5349: 5347: 5343: 5337: 5331: 5328: 5326: 5323: 5321: 5318: 5316: 5313: 5311: 5308: 5306: 5303: 5301: 5298: 5296: 5293: 5291: 5288: 5286: 5283: 5281: 5278: 5276: 5273: 5272: 5270: 5266: 5260: 5259:Weak ordering 5257: 5255: 5252: 5250: 5247: 5245: 5244:Partial order 5242: 5240: 5237: 5235: 5232: 5230: 5227: 5225: 5222: 5221: 5219: 5215: 5209: 5206: 5204: 5201: 5199: 5196: 5195: 5192: 5188: 5181: 5176: 5174: 5169: 5167: 5162: 5161: 5158: 5148: 5147: 5142: 5134: 5128: 5125: 5123: 5120: 5118: 5115: 5113: 5110: 5106: 5103: 5102: 5101: 5098: 5096: 5093: 5091: 5088: 5086: 5082: 5079: 5077: 5074: 5072: 5069: 5067: 5064: 5062: 5059: 5058: 5056: 5052: 5046: 5043: 5041: 5038: 5036: 5035:Recursive set 5033: 5031: 5028: 5026: 5023: 5021: 5018: 5016: 5013: 5009: 5006: 5004: 5001: 4999: 4996: 4994: 4991: 4989: 4986: 4985: 4984: 4981: 4979: 4976: 4974: 4971: 4969: 4966: 4964: 4961: 4959: 4956: 4955: 4953: 4951: 4947: 4941: 4938: 4936: 4933: 4931: 4928: 4926: 4923: 4921: 4918: 4916: 4913: 4911: 4908: 4904: 4901: 4899: 4896: 4894: 4891: 4890: 4889: 4886: 4884: 4881: 4879: 4876: 4874: 4871: 4869: 4866: 4864: 4861: 4857: 4854: 4853: 4852: 4849: 4845: 4844:of arithmetic 4842: 4841: 4840: 4837: 4833: 4830: 4828: 4825: 4823: 4820: 4818: 4815: 4813: 4810: 4809: 4808: 4805: 4801: 4798: 4796: 4793: 4792: 4791: 4788: 4787: 4785: 4783: 4779: 4773: 4770: 4768: 4765: 4763: 4760: 4758: 4755: 4752: 4751:from ZFC 4748: 4745: 4743: 4740: 4734: 4731: 4730: 4729: 4726: 4724: 4721: 4719: 4716: 4715: 4714: 4711: 4709: 4706: 4704: 4701: 4699: 4696: 4694: 4691: 4689: 4686: 4684: 4681: 4680: 4678: 4676: 4672: 4662: 4661: 4657: 4656: 4651: 4650:non-Euclidean 4648: 4644: 4641: 4639: 4636: 4634: 4633: 4629: 4628: 4626: 4623: 4622: 4620: 4616: 4612: 4609: 4607: 4604: 4603: 4602: 4598: 4594: 4591: 4590: 4589: 4585: 4581: 4578: 4576: 4573: 4571: 4568: 4566: 4563: 4561: 4558: 4556: 4553: 4552: 4550: 4546: 4545: 4543: 4538: 4532: 4527:Example  4524: 4516: 4511: 4510: 4509: 4506: 4504: 4501: 4497: 4494: 4492: 4489: 4487: 4484: 4482: 4479: 4478: 4477: 4474: 4472: 4469: 4467: 4464: 4462: 4459: 4455: 4452: 4450: 4447: 4446: 4445: 4442: 4438: 4435: 4433: 4430: 4428: 4425: 4423: 4420: 4419: 4418: 4415: 4413: 4410: 4406: 4403: 4401: 4398: 4396: 4393: 4392: 4391: 4388: 4384: 4381: 4379: 4376: 4374: 4371: 4369: 4366: 4364: 4361: 4359: 4356: 4355: 4354: 4351: 4349: 4346: 4344: 4341: 4339: 4336: 4332: 4329: 4327: 4324: 4322: 4319: 4317: 4314: 4313: 4312: 4309: 4307: 4304: 4302: 4299: 4297: 4294: 4290: 4287: 4285: 4284:by definition 4282: 4281: 4280: 4277: 4273: 4270: 4269: 4268: 4265: 4263: 4260: 4258: 4255: 4253: 4250: 4248: 4245: 4244: 4241: 4238: 4236: 4232: 4227: 4221: 4217: 4207: 4204: 4202: 4199: 4197: 4194: 4192: 4189: 4187: 4184: 4182: 4179: 4177: 4174: 4172: 4171:Kripke–Platek 4169: 4167: 4164: 4160: 4157: 4155: 4152: 4151: 4150: 4147: 4146: 4144: 4140: 4132: 4129: 4128: 4127: 4124: 4122: 4119: 4115: 4112: 4111: 4110: 4107: 4105: 4102: 4100: 4097: 4095: 4092: 4090: 4087: 4084: 4080: 4076: 4073: 4069: 4066: 4064: 4061: 4059: 4056: 4055: 4054: 4050: 4047: 4046: 4044: 4042: 4038: 4034: 4026: 4023: 4021: 4018: 4016: 4015:constructible 4013: 4012: 4011: 4008: 4006: 4003: 4001: 3998: 3996: 3993: 3991: 3988: 3986: 3983: 3981: 3978: 3976: 3973: 3971: 3968: 3966: 3963: 3961: 3958: 3956: 3953: 3951: 3948: 3947: 3945: 3943: 3938: 3930: 3927: 3925: 3922: 3920: 3917: 3915: 3912: 3910: 3907: 3905: 3902: 3901: 3899: 3895: 3892: 3890: 3887: 3886: 3885: 3882: 3880: 3877: 3875: 3872: 3870: 3867: 3865: 3861: 3857: 3855: 3852: 3848: 3845: 3844: 3843: 3840: 3839: 3836: 3833: 3831: 3827: 3817: 3814: 3812: 3809: 3807: 3804: 3802: 3799: 3797: 3794: 3792: 3789: 3785: 3782: 3781: 3780: 3777: 3773: 3768: 3767: 3766: 3763: 3762: 3760: 3758: 3754: 3746: 3743: 3741: 3738: 3736: 3733: 3732: 3731: 3728: 3726: 3723: 3721: 3718: 3716: 3713: 3711: 3708: 3706: 3703: 3701: 3698: 3697: 3695: 3693: 3692:Propositional 3689: 3683: 3680: 3678: 3675: 3673: 3670: 3668: 3665: 3663: 3660: 3658: 3655: 3651: 3648: 3647: 3646: 3643: 3641: 3638: 3636: 3633: 3631: 3628: 3626: 3623: 3621: 3620:Logical truth 3618: 3616: 3613: 3612: 3610: 3608: 3604: 3601: 3599: 3595: 3589: 3586: 3584: 3581: 3579: 3576: 3574: 3571: 3569: 3566: 3564: 3560: 3556: 3552: 3550: 3547: 3545: 3542: 3540: 3536: 3533: 3532: 3530: 3528: 3522: 3517: 3511: 3508: 3506: 3503: 3501: 3498: 3496: 3493: 3491: 3488: 3486: 3483: 3481: 3478: 3476: 3473: 3471: 3468: 3466: 3463: 3461: 3458: 3456: 3453: 3449: 3446: 3445: 3444: 3441: 3440: 3438: 3434: 3430: 3423: 3418: 3416: 3411: 3409: 3404: 3403: 3400: 3394: 3393:0-8247-7915-0 3390: 3387: 3386:Marcel Dekker 3383: 3379: 3375: 3374:Karel Hrbáček 3372: 3369: 3368:0-8218-0266-6 3365: 3362: 3358: 3354: 3353: 3346: 3340: 3325: 3323:9780444505422 3319: 3315: 3314: 3306: 3291: 3287: 3281: 3273: 3267: 3263: 3255: 3251: 3243: 3240: 3236: 3230: 3226: 3220: 3216: 3211: 3206: 3202: 3196: 3192: 3186: 3182: 3167: 3164: 3161: 3156: 3142: 3138: 3130: 3126: 3108: 3103: 3091: 3087: 3059: 3044: 3040: 3036: 3029: 3028:lexicographic 3025: 3018: 3017: 3016: 3001: 2998: 2995: 2986: 2982: 2979: 2975: 2968: 2961: 2952: 2945: 2935: 2928: 2921: 2914: 2909:, ordered by 2908: 2904: 2899: 2895: 2890: 2878: 2874: 2869: 2865: 2861: 2857: 2849: 2843: 2839: 2835: 2827: 2824:The positive 2823: 2822: 2821: 2813: 2811: 2807: 2803: 2799: 2794: 2792: 2786: 2780: 2776: 2770: 2764: 2756: 2753:is the usual 2746: 2742: 2733: 2728: 2721: 2717: 2710: 2707: 2704: 2701: 2694: 2690: 2683: 2679: 2665: 2652: 2648: 2641: 2637: 2633: 2629: 2625: 2622: 2618: 2609: 2606: 2603: 2599: 2595: 2592: 2586: 2580: 2571: 2567: 2552: 2549: 2546: 2542: 2537: 2528: 2524: 2517: 2513: 2509: 2500: 2494: 2490: 2484: 2479: 2477: 2472: 2459: 2453: 2447: 2440: 2437: 2434: 2412: 2406: 2392: 2386: 2378: 2374: 2370: 2360: 2357: 2354: 2338: 2335: 2332: 2312: 2308: 2302: 2299: 2296: 2285: 2281: 2268: 2267: 2266: 2250: 2246: 2242: 2241: 2240: 2232: 2228: 2222: 2218: 2213: 2203: 2201: 2197: 2193: 2180: 2176: 2168: 2164: 2160: 2151: 2149: 2145: 2137: 2133: 2129: 2121: 2116: 2114: 2110: 2106: 2102: 2101:partial order 2098: 2093: 2083: 2080: 2075: 2071: 2057: 2050: 2043: 2038: 2034: 2029: 2027: 2007: 1998: 1994: 1990: 1978: 1975: 1972: 1960: 1957: 1954: 1937: 1934: 1924: 1921: 1918: 1903: 1900: 1897: 1891: 1887: 1881: 1877: 1868: 1863: 1859: 1855: 1852: 1845: 1841: 1837: 1833: 1829: 1822: 1818: 1807: 1792: 1789: 1786: 1783: 1763: 1760: 1757: 1737: 1734: 1731: 1711: 1708: 1705: 1702: 1699: 1696: 1688: 1672: 1665: 1633: 1632: 1609: 1606: 1603: 1588: 1585: 1582: 1571: 1557: 1554: 1551: 1539: 1525: 1522: 1519: 1512: 1485: 1482: 1479: 1468: 1441: 1438: 1435: 1424: 1397: 1383: 1365: 1362: 1359: 1349: 1346: 1343: 1333: 1326: 1323: 1312: 1294: 1287: 1284: 1274: 1271: 1268: 1258: 1255: 1252: 1241: 1223: 1220: 1217: 1203: 1200: 1197: 1185: 1171: 1165: 1162: 1142: 1139: 1136: 1128: 1127: 1124: 1121: 1119: 1116: 1114: 1111: 1109: 1106: 1104: 1101: 1099: 1096: 1094: 1091: 1089: 1088:Antisymmetric 1086: 1084: 1081: 1079: 1078: 1067: 1057: 1052: 1047: 1042: 1037: 1027: 1017: 1012: 1010: 1007: 1006: 995: 985: 980: 975: 970: 965: 960: 950: 945: 943: 940: 939: 928: 918: 913: 908: 903: 898: 893: 883: 878: 876: 873: 872: 866: 861: 851: 841: 836: 831: 826: 816: 811: 809: 806: 805: 799: 794: 784: 779: 769: 764: 759: 749: 744: 742: 739: 738: 732: 727: 717: 707: 697: 692: 687: 677: 672: 670: 667: 666: 660: 655: 645: 640: 635: 625: 615: 605: 600: 598: 597:Well-ordering 595: 594: 588: 583: 573: 568: 563: 553: 548: 543: 538: 535: 531: 530: 524: 519: 509: 504: 499: 489: 479: 474: 469: 467: 464: 463: 457: 452: 442: 437: 432: 427: 417: 407: 402: 400: 397: 396: 390: 385: 375: 370: 365: 360: 350: 345: 340: 338: 335: 334: 328: 323: 313: 308: 303: 298: 293: 283: 278: 276: 275:Partial order 273: 272: 266: 261: 251: 246: 241: 236: 231: 226: 221: 218: 211: 210: 204: 199: 189: 184: 179: 174: 169: 164: 154: 151: 147: 146: 143: 138: 136: 134: 132: 130: 127: 125: 123: 121: 120: 117: 114: 112: 109: 107: 104: 102: 99: 97: 94: 92: 89: 87: 84: 82: 81:Antisymmetric 79: 77: 74: 72: 71: 68: 67: 61: 56: 54: 49: 47: 42: 41: 38: 34: 30: 29: 22: 5633:& Orders 5611:Star product 5540:Well-founded 5539: 5493:Prefix order 5449:Distributive 5439:Complemented 5409:Foundational 5374:Completeness 5330:Zorn's lemma 5234:Cyclic order 5217:Key concepts 5187:Order theory 5137: 4935:Ultraproduct 4782:Model theory 4747:Independence 4683:Formal proof 4675:Proof theory 4658: 4631: 4588:real numbers 4560:second-order 4471:Substitution 4348:Metalanguage 4289:conservative 4262:Axiom schema 4206:Constructive 4176:Morse–Kelley 4142:Set theories 4121:Aleph number 4114:inaccessible 4020:Grothendieck 3904:intersection 3791:Higher-order 3779:Second-order 3725:Truth tables 3682:Venn diagram 3465:Formal proof 3381: 3356: 3344: 3339: 3327:. Retrieved 3312: 3305: 3293:. Retrieved 3289: 3280: 3261: 3254: 3238: 3234: 3228: 3224: 3218: 3214: 3204: 3200: 3194: 3190: 3184: 3180: 3165: 3162: 3159: 3148: 3136: 3128: 3124: 3104: 3089: 3085: 3057: 3053: 3014: 2999: 2996: 2993: 2966: 2959: 2950: 2943: 2933: 2926: 2919: 2912: 2897: 2893: 2876: 2872: 2859: 2855: 2837: 2833: 2819: 2795: 2784: 2773:, we obtain 2768: 2744: 2740: 2726: 2719: 2715: 2711: 2705: 2702: 2699: 2692: 2688: 2681: 2677: 2666: 2569: 2565: 2550: 2547: 2544: 2540: 2526: 2522: 2515: 2511: 2507: 2492: 2488: 2480: 2476:Emmy Noether 2473: 2318: 2310: 2306: 2300: 2297: 2294: 2283: 2279: 2264: 2248: 2244: 2230: 2226: 2220: 2216: 2209: 2199: 2178: 2166: 2162: 2158: 2152: 2127: 2126:is called a 2117: 2105:strict order 2097:order theory 2094: 2081: 2078: 2073: 2069: 2055: 2048: 2041: 2030: 1901: 1898: 1895: 1889: 1885: 1879: 1875: 1861: 1857: 1836:foundational 1835: 1831: 1828:well-founded 1827: 1814: 1661: 1098:Well-founded 1097: 216:(Quasiorder) 91:Well-founded 90: 5817:Riesz space 5778:Isomorphism 5654:Normal cone 5576:Composition 5510:Semilattice 5419:Homogeneous 5404:Equivalence 5254:Total order 5045:Type theory 4993:undecidable 4925:Truth value 4812:equivalence 4491:non-logical 4104:Enumeration 4094:Isomorphism 4041:cardinality 4025:Von Neumann 3990:Ultrafilter 3955:Uncountable 3889:equivalence 3806:Quantifiers 3796:Fixed-point 3765:First-order 3645:Consistency 3630:Proposition 3607:Traditional 3578:Lindström's 3568:Compactness 3510:Type theory 3455:Cardinality 3378:Thomas Jech 3329:20 February 3149:A relation 3145:Reflexivity 3113:on a class 3094:has length 2810:∈-induction 2200:terminating 2153:A relation 2109:total order 1832:wellfounded 1817:mathematics 1118:Irreflexive 399:Total order 111:Irreflexive 5785:Order type 5719:Cofinality 5560:Well-order 5535:Transitive 5424:Idempotent 5357:Asymmetric 4856:elementary 4549:arithmetic 4417:Quantifier 4395:functional 4267:Expression 3985:Transitive 3929:identities 3914:complement 3847:hereditary 3830:Set theory 3271:0387900241 3246:References 3121:such that 2292:such that 2167:Noetherian 2120:set theory 2113:well-order 2067:such that 1826:is called 1689:: for all 1687:transitive 1123:Asymmetric 116:Asymmetric 33:Transitive 5836:Upper set 5773:Embedding 5709:Antichain 5530:Tolerance 5520:Symmetric 5515:Semiorder 5461:Reflexive 5379:Connected 5127:Supertask 5030:Recursion 4988:decidable 4822:saturated 4800:of models 4723:deductive 4718:axiomatic 4638:Hilbert's 4625:Euclidean 4606:canonical 4529:axiomatic 4461:Signature 4390:Predicate 4279:Extension 4201:Ackermann 4126:Operation 4005:Universal 3995:Recursive 3970:Singleton 3965:Inhabited 3950:Countable 3940:Types of 3924:power set 3894:partition 3811:Predicate 3757:Predicate 3672:Syllogism 3662:Soundness 3635:Inference 3625:Tautology 3527:paradoxes 3290:ProofWiki 3155:reflexive 2438:∈ 2432:∀ 2403:⟹ 2383:⟹ 2358:∈ 2352:∀ 2336:∈ 2330:∀ 2319:That is, 2196:rewriting 2173:, if the 1985:¬ 1976:∈ 1970:∀ 1958:∈ 1952:∃ 1945:⟹ 1941:∅ 1938:≠ 1922:⊆ 1916:∀ 1851:non-empty 1849:if every 1600:not  1592:⇒ 1548:not  1483:∧ 1439:∨ 1337:⇒ 1327:≠ 1282:⇒ 1211:⇒ 1169:∅ 1166:≠ 1113:Reflexive 1108:Has meets 1103:Has joins 1093:Connected 1083:Symmetric 214:Preorder 141:reflexive 106:Reflexive 101:Has meets 96:Has joins 86:Connected 76:Symmetric 5856:Category 5631:Topology 5498:Preorder 5481:Eulerian 5444:Complete 5394:Directed 5384:Covering 5249:Preorder 5208:Category 5203:Glossary 5112:Logicism 5105:timeline 5081:Concrete 4940:Validity 4910:T-schema 4903:Kripke's 4898:Tarski's 4893:semantic 4883:Strength 4832:submodel 4827:spectrum 4795:function 4643:Tarski's 4632:Elements 4619:geometry 4575:Robinson 4496:variable 4481:function 4454:spectrum 4444:Sentence 4400:variable 4343:Language 4296:Relation 4257:Automata 4247:Alphabet 4231:language 4085:-jection 4063:codomain 4049:Function 4010:Universe 3980:Infinite 3884:Relation 3667:Validity 3657:Argument 3555:theorem, 3210:preorder 3098:for any 2925:) < ( 2891:The set 2826:integers 2816:Examples 2724:, where 2499:set-like 2122:, a set 2026:set-like 1657:✗ 1644:✗ 1054:✗ 1049:✗ 1044:✗ 1039:✗ 1014:✗ 982:✗ 977:✗ 972:✗ 967:✗ 962:✗ 947:✗ 915:✗ 910:✗ 905:✗ 900:✗ 895:✗ 880:✗ 868:✗ 863:✗ 838:✗ 833:✗ 828:✗ 813:✗ 801:✗ 796:✗ 781:✗ 766:✗ 761:✗ 746:✗ 734:✗ 729:✗ 694:✗ 689:✗ 674:✗ 662:✗ 657:✗ 642:✗ 637:✗ 602:✗ 590:✗ 585:✗ 570:✗ 565:✗ 550:✗ 545:✗ 540:✗ 526:✗ 521:✗ 506:✗ 501:✗ 476:✗ 471:✗ 459:✗ 454:✗ 439:✗ 434:✗ 429:✗ 404:✗ 392:✗ 387:✗ 372:✗ 367:✗ 362:✗ 347:✗ 342:✗ 330:✗ 325:✗ 310:✗ 305:✗ 300:✗ 295:✗ 280:✗ 268:✗ 263:✗ 248:✗ 243:✗ 238:✗ 233:✗ 228:✗ 223:✗ 206:✗ 201:✗ 186:✗ 181:✗ 176:✗ 171:✗ 166:✗ 5736:Duality 5714:Cofinal 5702:Related 5681:FrĂ©chet 5558:)  5434:Bounded 5429:Lattice 5402:)  5400:Partial 5268:Results 5239:Lattice 5054:Related 4851:Diagram 4749: ( 4728:Hilbert 4713:Systems 4708:Theorem 4586:of the 4531:systems 4311:Formula 4306:Grammar 4222: ( 4166:General 3879:Forcing 3864:Element 3784:Monadic 3559:paradox 3500:Theorem 3436:General 3380:(1999) 3060:, <) 2868:strings 2848:divides 2787:, <) 2771:, <) 2534:on the 2424:implies 2304:, then 2130:if the 1838:) on a 669:Lattice 5761:Subnet 5741:Filter 5691:Normed 5676:Banach 5642:& 5549:Better 5486:Strict 5476:Graded 5367:topics 5198:Topics 4817:finite 4580:Skolem 4533:  4508:Theory 4476:Symbol 4466:String 4449:atomic 4326:ground 4321:closed 4316:atomic 4272:ground 4235:syntax 4131:binary 4058:domain 3975:Finite 3740:finite 3598:Logics 3557:  3505:Theory 3391:  3376:& 3366:  3320:  3295:10 May 3268:  2777:, and 2761:gives 2734:, and 2485:. Let 2142:. The 1865:has a 1854:subset 1494:exists 1450:exists 1406:exists 35:  5751:Ideal 5729:Graph 5525:Total 5503:Total 5389:Dense 4807:Model 4555:Peano 4412:Proof 4252:Arity 4181:Naive 4068:image 4000:Fuzzy 3960:Empty 3909:union 3854:Class 3495:Model 3485:Lemma 3443:Axiom 3217:< 3183:< 3088:− 1, 3043:reals 2965:< 2949:< 2903:pairs 2875:< 2836:< 2497:be a 2061:, ... 1844:class 1776:then 139:Anti- 5342:list 4930:Type 4733:list 4537:list 4514:list 4503:Term 4437:rank 4331:open 4225:list 4037:Maps 3942:sets 3801:Free 3771:list 3521:list 3448:list 3389:ISBN 3364:ISBN 3331:2019 3318:ISBN 3297:2021 3266:ISBN 3232:and 3198:and 3139:, ∈) 3105:The 3041:(or 2957:and 2853:and 2697:for 2277:and 2099:, a 1830:(or 1819:, a 1750:and 1155:and 5756:Net 5556:Pre 4617:of 4599:of 4547:of 4079:Sur 4053:Map 3860:Ur- 3842:Set 3237:≰ 3157:if 3084:ω, 3054:If 3007:to 2905:of 2901:of 2671:on 2555:of 2269:If 2257:of 2169:on 2165:or 2157:is 2138:of 2118:In 2095:In 2024:is 1840:set 1834:or 1815:In 1724:if 1685:be 1395:min 5858:: 5003:NP 4627:: 4621:: 4551:: 4228:), 4083:Bi 4075:In 3359:, 3288:. 3227:≀ 3203:≠ 3193:≀ 3141:. 3127:, 3102:. 2932:, 2918:, 2896:× 2858:≠ 2793:. 2747:+1 2743:↩ 2718:, 2709:. 2573:, 2568:∈ 2543:: 2525:∈ 2514:, 2491:, 2478:. 2219:, 2202:. 2161:, 2115:. 2092:. 2076:+1 2054:, 2047:, 1888:∈ 1878:∈ 1860:⊆ 5554:( 5551:) 5547:( 5398:( 5345:) 5179:e 5172:t 5165:v 5083:/ 4998:P 4753:) 4539:) 4535:( 4432:∀ 4427:! 4422:∃ 4383:= 4378:↔ 4373:→ 4368:∧ 4363:√ 4358:ÂŹ 4081:/ 4077:/ 4051:/ 3862:) 3858:( 3745:∞ 3735:3 3523:) 3421:e 3414:t 3407:v 3370:. 3333:. 3299:. 3274:. 3239:a 3235:b 3229:b 3225:a 3219:b 3215:a 3205:b 3201:a 3195:b 3191:a 3185:b 3181:a 3171:a 3166:a 3163:R 3160:a 3151:R 3137:C 3135:( 3131:) 3129:R 3125:X 3123:( 3119:C 3115:X 3111:R 3100:n 3096:n 3090:n 3086:n 3080:X 3076:X 3072:x 3068:X 3064:x 3058:X 3056:( 3011:. 3009:b 3005:a 3000:b 2997:R 2994:a 2989:R 2980:. 2973:. 2970:2 2967:m 2963:2 2960:n 2954:1 2951:m 2947:1 2944:n 2939:) 2937:2 2934:m 2930:1 2927:m 2923:2 2920:n 2916:1 2913:n 2911:( 2898:N 2894:N 2888:. 2886:t 2882:s 2877:t 2873:s 2863:. 2860:b 2856:a 2851:b 2845:a 2838:b 2834:a 2785:N 2783:( 2769:N 2767:( 2759:S 2751:S 2745:x 2741:x 2736:S 2727:N 2722:) 2720:S 2716:N 2714:( 2706:x 2703:R 2700:y 2695:) 2693:y 2691:( 2689:G 2684:) 2682:x 2680:( 2678:G 2673:X 2669:G 2653:. 2649:) 2642:} 2638:x 2634:R 2630:y 2626:: 2623:y 2619:{ 2614:| 2610:G 2607:, 2604:x 2600:( 2596:F 2593:= 2590:) 2587:x 2584:( 2581:G 2570:X 2566:x 2561:G 2557:X 2553:} 2551:x 2548:R 2545:y 2541:y 2539:{ 2532:g 2527:X 2523:x 2518:) 2516:g 2512:x 2510:( 2508:F 2503:F 2495:) 2493:R 2489:X 2487:( 2460:. 2457:) 2454:x 2451:( 2448:P 2444:) 2441:X 2435:x 2429:( 2419:] 2416:) 2413:x 2410:( 2407:P 2399:] 2396:) 2393:y 2390:( 2387:P 2379:x 2375:R 2371:y 2368:[ 2364:) 2361:X 2355:y 2349:( 2346:[ 2342:) 2339:X 2333:x 2327:( 2313:) 2311:x 2309:( 2307:P 2301:x 2298:R 2295:y 2290:y 2286:) 2284:y 2282:( 2280:P 2275:X 2271:x 2261:, 2259:X 2255:x 2251:) 2249:x 2247:( 2245:P 2237:X 2233:) 2231:x 2229:( 2227:P 2221:R 2217:X 2188:R 2184:X 2179:R 2171:X 2155:R 2140:x 2124:x 2090:n 2085:n 2082:x 2079:R 2074:n 2070:x 2065:X 2059:2 2056:x 2052:1 2049:x 2045:0 2042:x 2022:R 2008:. 2005:] 2002:) 1999:m 1995:R 1991:s 1988:( 1982:) 1979:S 1973:s 1967:( 1964:) 1961:S 1955:m 1949:( 1935:S 1932:[ 1928:) 1925:X 1919:S 1913:( 1902:m 1899:R 1896:s 1890:S 1886:s 1880:S 1876:m 1871:R 1862:X 1858:S 1847:X 1824:R 1793:. 1790:c 1787:R 1784:a 1764:c 1761:R 1758:b 1738:b 1735:R 1732:a 1712:, 1709:c 1706:, 1703:b 1700:, 1697:a 1673:R 1653:Y 1640:Y 1610:a 1607:R 1604:b 1589:b 1586:R 1583:a 1558:a 1555:R 1552:a 1526:a 1523:R 1520:a 1486:b 1480:a 1442:b 1436:a 1398:S 1366:a 1363:R 1360:b 1350:b 1347:R 1344:a 1334:b 1324:a 1295:b 1288:= 1285:a 1275:a 1272:R 1269:b 1259:b 1256:R 1253:a 1224:a 1221:R 1218:b 1204:b 1201:R 1198:a 1172:: 1163:S 1143:b 1140:, 1137:a 1074:Y 1064:Y 1034:Y 1024:Y 1002:Y 992:Y 957:Y 935:Y 925:Y 890:Y 858:Y 848:Y 823:Y 791:Y 776:Y 756:Y 724:Y 714:Y 704:Y 684:Y 652:Y 632:Y 622:Y 612:Y 580:Y 560:Y 516:Y 496:Y 486:Y 449:Y 424:Y 414:Y 382:Y 357:Y 320:Y 290:Y 258:Y 196:Y 161:Y 59:e 52:t 45:v 23:.

Index

Noetherian topological space
Transitive
binary relations
v
t
e
Symmetric
Antisymmetric
Connected
Well-founded
Has joins
Has meets
Reflexive
Irreflexive
Asymmetric
Equivalence relation
Preorder (Quasiorder)
Partial order
Total preorder
Total order
Prewellordering
Well-quasi-ordering
Well-ordering
Lattice
Join-semilattice
Meet-semilattice
Strict partial order
Strict weak order
Strict total order
Symmetric

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