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Hausdorff maximal principle

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The proof that the Hausdorff maximal principle is equivalent to Zorn's lemma is somehow similar to this proof. Indeed, first assume Zorn's lemma. Since a union of a totally ordered set of chains is a chain, the hypothesis of Zorn's lemma (every chain has an upper bound) is satisfied for
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consists of all circular regions with centers at the origin. Another maximal totally ordered sub-collection consists of all circular regions bounded by circles tangent from the right to the y-axis at the origin.
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An equivalent form of the Hausdorff maximal principle is that in every partially ordered set, there exists a maximal chain. (Note if the set is empty, the empty subset is a maximal chain.)
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In a partially ordered set, a totally ordered subset is also called a chain. Thus, the maximal principle says every chain in the set extends to a maximal chain.
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This form follows from the original form since the empty set is a chain. Conversely, to deduce the original form from this form, consider the set
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under which two points are comparable only if they lie on the same horizontal line. The maximal totally ordered sets are horizontal lines in
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be a nonempty set of subsets of some fixed set, ordered by set inclusion, such that (1) the union of each totally ordered subset of
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is the collection of all circular regions (interiors of circles) in the plane. One maximal totally ordered sub-collection of
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is contained in a maximal totally ordered subset, where "maximal" is with respect to set inclusion.
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The idea of the proof is essentially due to Zermelo and is to prove the following weak form of
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For the purpose of comparison, here is a proof of the same fact by Zorn's lemma. As above, let
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is partially ordered by set inclusion. Thus, by the maximal principle in the above form,
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is a tower. The conditions 1. and 2. are again straightforward to check. For 3., let
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Real and Complex Analysis (International Series in Pure and Applied Mathematics)
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is a tower. The conditions 1. and 2. are straightforward to check. For 3., let
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is also orthonormal by the same argument as above and so is an upper bound of
173:). In general, there may be several maximal chains containing a given chain. 5334: 5207: 5013: 52:
The Hausdorff maximal principle is one of many statements equivalent to the
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is any collection of sets, the relation "is a proper subset of" is a
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since a union of a totally ordered set of chains is a chain. Since
153:(i.e., a chain that is not contained in a strictly larger chain in 1267:
be the set of all orthonormal subsets of the given Hilbert space
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There exists at least one tower; indeed, the set of all sets in
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without the axiom of choice). The principle is also called the
1347:. We shall show it is a maximal orthonormal subset. First, if 2968:
be the intersection of all towers, which is again a tower.
2798:, where "totally ordered" is with respect to set inclusion. 1505:
and so they are orthogonal to each other (and of course,
2102:{\displaystyle f:{\mathfrak {P}}(P)-\{\emptyset \}\to P} 1159:
By the Hausdorff maximal principle, we can show every
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as follows. (This fact can be stated as saying that
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The Hausdorff maximal principle states that, in any
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Reprinted by Springer-Verlag, New York, 1974. 35:in 1914 (Moore 1982:168). It states that in any 16:Mathematical result or axiom on order relations 1445:. That is, any given two distinct elements in 4670: 4108:. This completes the proof of the claim that 8: 2458: 2436: 2304: 2298: 2090: 2084: 1670: 1664: 851:{\displaystyle {\widetilde {C}}=C\cup \{y\}} 845: 839: 2052:By the axiom of choice, we have a function 27:is an alternate and earlier formulation of 5328:Positive cone of a partially ordered group 4677: 4663: 4655: 4591:. Princeton, NJ: D. Van Nostrand Company. 4513: 4481: 4480: 4478: 4466:{\displaystyle {\widetilde {C}}\subset C} 4446: 4445: 4443: 4422: 4416: 4396: 4375: 4369: 4343: 4342: 4340: 4319: 4313: 4293: 4272: 4266: 4246: 4222: 4216: 4189: 4183: 4162: 4156: 4136: 4113: 4093: 4072: 4066: 4040: 4039: 4037: 4016: 4004: 3983: 3977: 3956: 3944: 3924: 3904: 3878: 3877: 3875: 3849: 3829: 3803: 3802: 3800: 3774: 3773: 3771: 3745: 3744: 3736: 3710: 3684: 3683: 3669: 3649: 3623: 3622: 3620: 3608:{\displaystyle C\subset {\widetilde {A}}} 3594: 3593: 3585: 3573:{\displaystyle {\widetilde {A}}\subset C} 3553: 3552: 3550: 3529: 3523: 3503: 3477: 3457: 3437: 3417: 3402:{\displaystyle {\widetilde {C}}\subset A} 3382: 3381: 3379: 3353: 3332: 3326: 3306: 3286: 3266: 3246: 3226: 3205: 3199: 3178: 3172: 3152: 3126: 3100: 3079: 3073: 3053: 3031: 3025: 3003: 2982: 2976: 2952: 2946: 2925: 2919: 2899: 2875: 2849: 2848: 2846: 2826: 2806: 2783: 2752: 2747:The union of each totally ordered subset 2729: 2708: 2702: 2676: 2670: 2642: 2622: 2601: 2595: 2560: 2559: 2557: 2537: 2505: 2504: 2502: 2482: 2449: 2416: 2415: 2413: 2378: 2377: 2375: 2348: 2342: 2322: 2290: 2258: 2237: 2231: 2205: 2182: 2152: 2151: 2149: 2114: 2066: 2065: 2057: 2034: 2010: 1990: 1970: 1950: 1930: 1910: 1870: 1850: 1830: 1810: 1790: 1770: 1750: 1745:be the set of all orthonormal subsets of 1730: 1708: 1688: 1656: 1636: 1616: 1596: 1576: 1550: 1530: 1510: 1490: 1470: 1450: 1424: 1398: 1378: 1352: 1332: 1312: 1292: 1272: 1252: 1219: 1207: 1187: 1167: 1135: 1131: 1130: 1127: 1106: 1102: 1101: 1098: 1045: 1041: 1040: 1037: 970: 944: 918: 886: 885: 883: 863: 819: 818: 816: 790: 770: 750: 730: 710: 690: 667: 642: 617: 593: 568: 548: 528: 508: 488: 463: 442: 436: 416: 396: 371: 351: 326: 301: 276: 256: 235: 229: 209: 184: 158: 138: 110: 104: 84: 5311:Positive cone of an ordered vector space 4536: 4555: 1182:contains a maximal orthonormal subset 4567: 4543: 2532:. Thus, we are done if we can find a 725:. By the hypothesis of Zorn's lemma, 7: 2497:is a maximal element if and only if 1237:{\displaystyle H\simeq \ell ^{2}(A)} 3999:is the intersection of all towers, 2153: 2067: 483:. Also, since any chain containing 4838:Properties & Types ( 4501:{\displaystyle {\widetilde {C}}=C} 4198: 4138: 4115: 4095: 3759:{\displaystyle C={\widetilde {A}}} 3268: 3228: 3154: 2580:{\displaystyle {\widetilde {C}}=C} 2525:{\displaystyle {\widetilde {C}}=C} 2398:{\displaystyle {\widetilde {C}}=C} 2357: 2170:{\displaystyle {\mathfrak {P}}(P)} 2087: 1525:is a subset of the unit sphere in 906:{\displaystyle {\widetilde {C}}=C} 133:) is contained in a maximal chain 14: 5294:Positive cone of an ordered field 2998:is totally ordered. We say a set 5148:Ordered topological vector space 4357:{\displaystyle {\widetilde {C}}} 4054:{\displaystyle {\widetilde {C}}} 3892:{\displaystyle {\widetilde {A}}} 3817:{\displaystyle {\widetilde {A}}} 3788:{\displaystyle {\widetilde {A}}} 3637:{\displaystyle {\widetilde {A}}} 2863:{\displaystyle {\widetilde {C}}} 2363:{\displaystyle C^{*}=\emptyset } 2049:satisfies the above conditions. 1965:and (2) each subset of a set in 1683:is a chain strictly larger than 1144:{\displaystyle \mathbb {R} ^{2}} 1115:{\displaystyle \mathbb {R} ^{2}} 1093:. This is a partial ordering of 1054:{\displaystyle \mathbb {R} ^{2}} 563:is in fact a maximal element of 3965:{\displaystyle U\subset T_{0}} 3664:. In the second case, we have 2455: 2442: 2164: 2158: 2125: 2119: 2093: 2078: 2072: 1231: 1225: 1032:) are two points of the plane 1: 5105:Series-parallel partial order 4204:{\displaystyle T_{0}=\Gamma } 1564:{\displaystyle B\supsetneq A} 4784:Cantor's isomorphism theorem 62:Hausdorff maximality theorem 4824:Szpilrajn extension theorem 4799:Hausdorff maximal principle 4774:Boolean prime ideal theorem 2771:{\displaystyle T'\subset T} 2310:{\displaystyle C\cup \{x\}} 1865:contains a maximal element 1676:{\displaystyle Q\cup \{B\}} 588:; i.e., a maximal chain in 58:Zermelo–Fraenkel set theory 25:Hausdorff maximal principle 5387: 5170:Topological vector lattice 4601:(Springer-Verlag edition). 3863:{\displaystyle C\subset A} 3491:{\displaystyle A\subset C} 3367:{\displaystyle A\subset C} 3167:be the set of all sets in 3140:{\displaystyle C\subset A} 3114:{\displaystyle A\subset C} 2656:{\displaystyle T\subset F} 1438:{\displaystyle T\subset S} 1412:{\displaystyle S\subset T} 4692: 4616:Zermelo's axiom of choice 2137:{\displaystyle f(S)\in S} 1845:. Thus, by Zorn's lemma, 705:contains a maximal chain 321:contains a maximal chain 224:containing a given chain 4779:Cantor–Bernstein theorem 4521:{\displaystyle \square } 4151:is a tower contained in 2278:{\displaystyle x\in P-C} 1716:{\displaystyle \square } 978:{\displaystyle \square } 5366:Mathematical principles 5323:Partially ordered group 5143:Specialization preorder 4144:{\displaystyle \Gamma } 4121:{\displaystyle \Gamma } 4101:{\displaystyle \Gamma } 4025:{\displaystyle U=T_{0}} 3939:is a tower. Now, since 3795:.) Either way, we have 3705:, which implies either 3274:{\displaystyle \Gamma } 3234:{\displaystyle \Gamma } 3194:that are comparable in 3160:{\displaystyle \Gamma } 804:{\displaystyle y\geq x} 4809:Kruskal's tree theorem 4804:Knaster–Tarski theorem 4794:Dushnik–Miller theorem 4614:Gregory Moore (1982), 4522: 4502: 4467: 4432: 4405: 4385: 4358: 4329: 4302: 4282: 4255: 4232: 4205: 4172: 4145: 4122: 4102: 4082: 4055: 4026: 3993: 3966: 3933: 3913: 3893: 3864: 3838: 3818: 3789: 3760: 3725: 3699: 3658: 3638: 3609: 3574: 3539: 3512: 3492: 3466: 3446: 3426: 3403: 3368: 3342: 3315: 3295: 3281:be given and then let 3275: 3255: 3235: 3215: 3188: 3161: 3141: 3115: 3089: 3062: 3041: 3012: 2992: 2962: 2935: 2908: 2884: 2864: 2835: 2815: 2792: 2772: 2738: 2718: 2686: 2657: 2631: 2611: 2581: 2546: 2526: 2491: 2468: 2399: 2364: 2331: 2311: 2279: 2247: 2220: 2219:{\displaystyle C\in F} 2191: 2171: 2138: 2103: 2043: 2025:has a maximal element. 2019: 1999: 1979: 1959: 1939: 1919: 1879: 1859: 1839: 1819: 1799: 1779: 1759: 1739: 1717: 1697: 1677: 1645: 1625: 1605: 1585: 1565: 1539: 1519: 1499: 1479: 1465:are contained in some 1459: 1439: 1413: 1387: 1367: 1341: 1321: 1301: 1281: 1261: 1238: 1196: 1176: 1145: 1116: 1055: 979: 959: 933: 932:{\displaystyle y\in C} 907: 878:and so by maximality, 872: 858:is a chain containing 852: 805: 779: 759: 739: 719: 699: 676: 656: 631: 602: 582: 557: 537: 517: 497: 477: 458:, it is an element of 452: 425: 405: 391:, which is a chain in 385: 360: 340: 315: 290: 265: 245: 218: 198: 167: 147: 120: 93: 4523: 4503: 4468: 4433: 4431:{\displaystyle T_{0}} 4406: 4386: 4384:{\displaystyle T_{0}} 4359: 4330: 4328:{\displaystyle T_{0}} 4303: 4283: 4281:{\displaystyle T_{0}} 4256: 4233: 4231:{\displaystyle T_{0}} 4206: 4173: 4171:{\displaystyle T_{0}} 4146: 4123: 4103: 4083: 4081:{\displaystyle T_{0}} 4056: 4027: 3994: 3992:{\displaystyle T_{0}} 3967: 3934: 3914: 3894: 3865: 3839: 3819: 3790: 3761: 3726: 3700: 3659: 3639: 3615:. In the first case, 3610: 3575: 3540: 3538:{\displaystyle T_{0}} 3513: 3493: 3467: 3447: 3427: 3404: 3369: 3343: 3341:{\displaystyle T_{0}} 3316: 3296: 3276: 3256: 3236: 3216: 3214:{\displaystyle T_{0}} 3189: 3187:{\displaystyle T_{0}} 3162: 3142: 3116: 3090: 3088:{\displaystyle T_{0}} 3063: 3042: 3040:{\displaystyle T_{0}} 3013: 2993: 2991:{\displaystyle T_{0}} 2963: 2961:{\displaystyle T_{0}} 2936: 2934:{\displaystyle C_{0}} 2909: 2885: 2865: 2836: 2816: 2793: 2773: 2739: 2719: 2717:{\displaystyle C_{0}} 2687: 2685:{\displaystyle C_{0}} 2658: 2632: 2612: 2610:{\displaystyle C_{0}} 2582: 2547: 2527: 2492: 2469: 2400: 2365: 2332: 2312: 2280: 2248: 2246:{\displaystyle C^{*}} 2221: 2192: 2172: 2139: 2104: 2044: 2020: 2000: 1980: 1960: 1940: 1920: 1880: 1860: 1840: 1820: 1800: 1780: 1760: 1740: 1718: 1698: 1678: 1646: 1626: 1606: 1586: 1566: 1540: 1520: 1500: 1480: 1460: 1440: 1414: 1388: 1368: 1342: 1322: 1302: 1282: 1262: 1239: 1197: 1177: 1146: 1117: 1056: 980: 960: 934: 908: 873: 853: 806: 780: 760: 740: 720: 700: 677: 657: 632: 603: 583: 558: 538: 518: 498: 478: 453: 451:{\displaystyle C_{0}} 426: 406: 386: 361: 341: 316: 291: 266: 246: 244:{\displaystyle C_{0}} 219: 199: 168: 148: 121: 119:{\displaystyle C_{0}} 94: 78:partially ordered set 37:partially ordered set 5301:Ordered vector space 4512: 4477: 4442: 4415: 4395: 4368: 4339: 4312: 4292: 4265: 4245: 4238:is totally ordered. 4215: 4182: 4155: 4135: 4112: 4092: 4065: 4036: 4003: 3976: 3943: 3923: 3903: 3874: 3848: 3828: 3799: 3770: 3735: 3709: 3668: 3648: 3619: 3584: 3549: 3522: 3502: 3476: 3456: 3436: 3416: 3378: 3352: 3325: 3305: 3285: 3265: 3245: 3225: 3198: 3171: 3151: 3125: 3099: 3072: 3052: 3024: 3002: 2975: 2945: 2918: 2898: 2874: 2845: 2825: 2805: 2782: 2751: 2728: 2701: 2669: 2641: 2621: 2594: 2556: 2536: 2501: 2481: 2412: 2374: 2341: 2321: 2289: 2257: 2230: 2204: 2181: 2148: 2113: 2056: 2033: 2009: 1989: 1969: 1949: 1929: 1909: 1869: 1849: 1829: 1809: 1805:, then the union of 1789: 1769: 1749: 1729: 1707: 1687: 1655: 1635: 1615: 1595: 1575: 1549: 1529: 1509: 1489: 1469: 1449: 1423: 1397: 1377: 1351: 1331: 1311: 1291: 1271: 1251: 1244:as Hilbert spaces.) 1206: 1186: 1166: 1126: 1097: 1036: 998:strict partial order 969: 943: 917: 882: 862: 815: 789: 769: 749: 729: 709: 689: 666: 641: 616: 592: 567: 547: 527: 507: 487: 462: 435: 415: 395: 370: 350: 325: 300: 275: 255: 228: 208: 183: 157: 137: 103: 83: 5139:Alexandrov topology 5085:Lexicographic order 5044:Well-quasi-ordering 3724:{\displaystyle A=C} 2971:Now, we shall show 2637:. We call a subset 1703:, a contradiction. 1366:{\displaystyle S,T} 958:{\displaystyle y=x} 745:has an upper bound 5120:Transitive closure 5080:Converse/Transpose 4789:Dilworth's theorem 4518: 4498: 4463: 4428: 4401: 4381: 4354: 4325: 4298: 4278: 4251: 4228: 4201: 4168: 4141: 4118: 4098: 4078: 4051: 4022: 3989: 3962: 3929: 3909: 3889: 3860: 3834: 3814: 3785: 3756: 3721: 3695: 3654: 3634: 3605: 3570: 3535: 3508: 3488: 3462: 3442: 3422: 3399: 3364: 3338: 3311: 3301:be the set of all 3291: 3271: 3251: 3231: 3211: 3184: 3157: 3137: 3111: 3085: 3058: 3037: 3008: 2988: 2958: 2931: 2904: 2880: 2860: 2831: 2811: 2788: 2768: 2734: 2714: 2682: 2653: 2627: 2607: 2577: 2542: 2522: 2487: 2464: 2395: 2360: 2327: 2307: 2275: 2253:be the set of all 2243: 2216: 2187: 2167: 2144:for the power set 2134: 2099: 2039: 2015: 1995: 1975: 1955: 1935: 1915: 1875: 1855: 1835: 1815: 1795: 1775: 1755: 1735: 1713: 1693: 1673: 1641: 1621: 1601: 1581: 1561: 1535: 1515: 1495: 1475: 1455: 1435: 1409: 1383: 1363: 1337: 1317: 1297: 1277: 1257: 1234: 1192: 1172: 1141: 1112: 1051: 975: 955: 929: 903: 868: 848: 801: 775: 755: 735: 715: 695: 672: 655:{\displaystyle P'} 652: 630:{\displaystyle P'} 627: 598: 581:{\displaystyle P'} 578: 553: 533: 513: 493: 476:{\displaystyle P'} 473: 448: 421: 401: 384:{\displaystyle C'} 381: 356: 339:{\displaystyle C'} 336: 314:{\displaystyle P'} 311: 289:{\displaystyle P'} 286: 261: 241: 214: 197:{\displaystyle P'} 194: 163: 143: 116: 89: 68:(Kelley 1955:33). 5348: 5347: 5306:Partially ordered 5115:Symmetric closure 5100:Reflexive closure 4843: 4647:978-0-07-054234-1 4489: 4454: 4404:{\displaystyle C} 4351: 4301:{\displaystyle C} 4254:{\displaystyle C} 4061:is comparable in 4048: 3932:{\displaystyle U} 3912:{\displaystyle U} 3886: 3837:{\displaystyle U} 3811: 3782: 3753: 3692: 3657:{\displaystyle U} 3631: 3602: 3561: 3518:is comparable in 3511:{\displaystyle C} 3465:{\displaystyle U} 3445:{\displaystyle A} 3425:{\displaystyle U} 3390: 3348:such that either 3314:{\displaystyle A} 3294:{\displaystyle U} 3254:{\displaystyle C} 3061:{\displaystyle A} 3011:{\displaystyle C} 2907:{\displaystyle F} 2883:{\displaystyle T} 2857: 2834:{\displaystyle T} 2814:{\displaystyle C} 2791:{\displaystyle T} 2737:{\displaystyle T} 2630:{\displaystyle F} 2568: 2545:{\displaystyle C} 2513: 2490:{\displaystyle C} 2424: 2405:. Otherwise, let 2386: 2330:{\displaystyle F} 2190:{\displaystyle P} 2042:{\displaystyle P} 2018:{\displaystyle F} 1998:{\displaystyle F} 1978:{\displaystyle F} 1958:{\displaystyle F} 1938:{\displaystyle F} 1918:{\displaystyle F} 1878:{\displaystyle A} 1858:{\displaystyle P} 1838:{\displaystyle Q} 1818:{\displaystyle Q} 1798:{\displaystyle P} 1778:{\displaystyle Q} 1758:{\displaystyle H} 1738:{\displaystyle P} 1696:{\displaystyle Q} 1644:{\displaystyle Q} 1624:{\displaystyle B} 1604:{\displaystyle P} 1584:{\displaystyle B} 1538:{\displaystyle H} 1518:{\displaystyle A} 1498:{\displaystyle Q} 1478:{\displaystyle S} 1458:{\displaystyle A} 1386:{\displaystyle Q} 1340:{\displaystyle Q} 1320:{\displaystyle A} 1300:{\displaystyle Q} 1280:{\displaystyle H} 1260:{\displaystyle P} 1195:{\displaystyle A} 1175:{\displaystyle H} 894: 871:{\displaystyle C} 827: 778:{\displaystyle P} 758:{\displaystyle x} 738:{\displaystyle C} 718:{\displaystyle C} 698:{\displaystyle P} 675:{\displaystyle P} 601:{\displaystyle P} 556:{\displaystyle C} 536:{\displaystyle C} 516:{\displaystyle C} 496:{\displaystyle C} 424:{\displaystyle C} 404:{\displaystyle P} 359:{\displaystyle C} 264:{\displaystyle P} 217:{\displaystyle P} 204:of all chains in 166:{\displaystyle P} 146:{\displaystyle C} 92:{\displaystyle P} 5378: 5090:Linear extension 4839: 4819:Mirsky's theorem 4679: 4672: 4665: 4656: 4651: 4609:General topology 4592: 4589:Naive set theory 4571: 4565: 4559: 4553: 4547: 4541: 4527: 4525: 4524: 4519: 4507: 4505: 4504: 4499: 4491: 4490: 4482: 4472: 4470: 4469: 4464: 4456: 4455: 4447: 4437: 4435: 4434: 4429: 4427: 4426: 4411:is the union of 4410: 4408: 4407: 4402: 4390: 4388: 4387: 4382: 4380: 4379: 4363: 4361: 4360: 4355: 4353: 4352: 4344: 4335:and then by 3., 4334: 4332: 4331: 4326: 4324: 4323: 4307: 4305: 4304: 4299: 4287: 4285: 4284: 4279: 4277: 4276: 4261:be the union of 4260: 4258: 4257: 4252: 4237: 4235: 4234: 4229: 4227: 4226: 4210: 4208: 4207: 4202: 4194: 4193: 4177: 4175: 4174: 4169: 4167: 4166: 4150: 4148: 4147: 4142: 4127: 4125: 4124: 4119: 4107: 4105: 4104: 4099: 4087: 4085: 4084: 4079: 4077: 4076: 4060: 4058: 4057: 4052: 4050: 4049: 4041: 4032:, which implies 4031: 4029: 4028: 4023: 4021: 4020: 3998: 3996: 3995: 3990: 3988: 3987: 3971: 3969: 3968: 3963: 3961: 3960: 3938: 3936: 3935: 3930: 3918: 3916: 3915: 3910: 3898: 3896: 3895: 3890: 3888: 3887: 3879: 3869: 3867: 3866: 3861: 3844:. Similarly, if 3843: 3841: 3840: 3835: 3823: 3821: 3820: 3815: 3813: 3812: 3804: 3794: 3792: 3791: 3786: 3784: 3783: 3775: 3765: 3763: 3762: 3757: 3755: 3754: 3746: 3730: 3728: 3727: 3722: 3704: 3702: 3701: 3696: 3694: 3693: 3685: 3663: 3661: 3660: 3655: 3643: 3641: 3640: 3635: 3633: 3632: 3624: 3614: 3612: 3611: 3606: 3604: 3603: 3595: 3579: 3577: 3576: 3571: 3563: 3562: 3554: 3544: 3542: 3541: 3536: 3534: 3533: 3517: 3515: 3514: 3509: 3497: 3495: 3494: 3489: 3471: 3469: 3468: 3463: 3451: 3449: 3448: 3443: 3431: 3429: 3428: 3423: 3408: 3406: 3405: 3400: 3392: 3391: 3383: 3373: 3371: 3370: 3365: 3347: 3345: 3344: 3339: 3337: 3336: 3320: 3318: 3317: 3312: 3300: 3298: 3297: 3292: 3280: 3278: 3277: 3272: 3260: 3258: 3257: 3252: 3240: 3238: 3237: 3232: 3220: 3218: 3217: 3212: 3210: 3209: 3193: 3191: 3190: 3185: 3183: 3182: 3166: 3164: 3163: 3158: 3146: 3144: 3143: 3138: 3120: 3118: 3117: 3112: 3094: 3092: 3091: 3086: 3084: 3083: 3067: 3065: 3064: 3059: 3046: 3044: 3043: 3038: 3036: 3035: 3017: 3015: 3014: 3009: 2997: 2995: 2994: 2989: 2987: 2986: 2967: 2965: 2964: 2959: 2957: 2956: 2941:is a tower. Let 2940: 2938: 2937: 2932: 2930: 2929: 2913: 2911: 2910: 2905: 2889: 2887: 2886: 2881: 2869: 2867: 2866: 2861: 2859: 2858: 2850: 2840: 2838: 2837: 2832: 2820: 2818: 2817: 2812: 2797: 2795: 2794: 2789: 2777: 2775: 2774: 2769: 2761: 2743: 2741: 2740: 2735: 2723: 2721: 2720: 2715: 2713: 2712: 2691: 2689: 2688: 2683: 2681: 2680: 2662: 2660: 2659: 2654: 2636: 2634: 2633: 2628: 2616: 2614: 2613: 2608: 2606: 2605: 2586: 2584: 2583: 2578: 2570: 2569: 2561: 2551: 2549: 2548: 2543: 2531: 2529: 2528: 2523: 2515: 2514: 2506: 2496: 2494: 2493: 2488: 2473: 2471: 2470: 2465: 2454: 2453: 2426: 2425: 2417: 2404: 2402: 2401: 2396: 2388: 2387: 2379: 2369: 2367: 2366: 2361: 2353: 2352: 2336: 2334: 2333: 2328: 2316: 2314: 2313: 2308: 2284: 2282: 2281: 2276: 2252: 2250: 2249: 2244: 2242: 2241: 2225: 2223: 2222: 2217: 2196: 2194: 2193: 2188: 2176: 2174: 2173: 2168: 2157: 2156: 2143: 2141: 2140: 2135: 2108: 2106: 2105: 2100: 2071: 2070: 2048: 2046: 2045: 2040: 2024: 2022: 2021: 2016: 2004: 2002: 2001: 1996: 1984: 1982: 1981: 1976: 1964: 1962: 1961: 1956: 1944: 1942: 1941: 1936: 1924: 1922: 1921: 1916: 1884: 1882: 1881: 1876: 1864: 1862: 1861: 1856: 1844: 1842: 1841: 1836: 1824: 1822: 1821: 1816: 1804: 1802: 1801: 1796: 1784: 1782: 1781: 1776: 1764: 1762: 1761: 1756: 1744: 1742: 1741: 1736: 1722: 1720: 1719: 1714: 1702: 1700: 1699: 1694: 1682: 1680: 1679: 1674: 1650: 1648: 1647: 1642: 1630: 1628: 1627: 1622: 1610: 1608: 1607: 1602: 1590: 1588: 1587: 1582: 1570: 1568: 1567: 1562: 1544: 1542: 1541: 1536: 1524: 1522: 1521: 1516: 1504: 1502: 1501: 1496: 1484: 1482: 1481: 1476: 1464: 1462: 1461: 1456: 1444: 1442: 1441: 1436: 1418: 1416: 1415: 1410: 1392: 1390: 1389: 1384: 1372: 1370: 1369: 1364: 1346: 1344: 1343: 1338: 1327:be the union of 1326: 1324: 1323: 1318: 1306: 1304: 1303: 1298: 1286: 1284: 1283: 1278: 1266: 1264: 1263: 1258: 1243: 1241: 1240: 1235: 1224: 1223: 1201: 1199: 1198: 1193: 1181: 1179: 1178: 1173: 1150: 1148: 1147: 1142: 1140: 1139: 1134: 1121: 1119: 1118: 1113: 1111: 1110: 1105: 1060: 1058: 1057: 1052: 1050: 1049: 1044: 984: 982: 981: 976: 964: 962: 961: 956: 938: 936: 935: 930: 912: 910: 909: 904: 896: 895: 887: 877: 875: 874: 869: 857: 855: 854: 849: 829: 828: 820: 810: 808: 807: 802: 784: 782: 781: 776: 764: 762: 761: 756: 744: 742: 741: 736: 724: 722: 721: 716: 704: 702: 701: 696: 681: 679: 678: 673: 661: 659: 658: 653: 651: 636: 634: 633: 628: 626: 607: 605: 604: 599: 587: 585: 584: 579: 577: 562: 560: 559: 554: 542: 540: 539: 534: 522: 520: 519: 514: 503:is contained in 502: 500: 499: 494: 482: 480: 479: 474: 472: 457: 455: 454: 449: 447: 446: 430: 428: 427: 422: 410: 408: 407: 402: 390: 388: 387: 382: 380: 366:be the union of 365: 363: 362: 357: 345: 343: 342: 337: 335: 320: 318: 317: 312: 310: 295: 293: 292: 287: 285: 270: 268: 267: 262: 250: 248: 247: 242: 240: 239: 223: 221: 220: 215: 203: 201: 200: 195: 193: 172: 170: 169: 164: 152: 150: 149: 144: 125: 123: 122: 117: 115: 114: 98: 96: 95: 90: 66:Kuratowski lemma 5386: 5385: 5381: 5380: 5379: 5377: 5376: 5375: 5361:Axiom of choice 5351: 5350: 5349: 5344: 5340:Young's lattice 5196: 5124: 5063: 4913:Heyting algebra 4861:Boolean algebra 4833: 4814:Laver's theorem 4762: 4728:Boolean algebra 4723:Binary relation 4711: 4688: 4683: 4648: 4640:. McGraw-Hill. 4632: 4611:, Von Nostrand. 4583: 4580: 4575: 4574: 4566: 4562: 4554: 4550: 4546:, Theorem 4.22. 4542: 4538: 4533: 4510: 4509: 4475: 4474: 4440: 4439: 4418: 4413: 4412: 4393: 4392: 4371: 4366: 4365: 4337: 4336: 4315: 4310: 4309: 4290: 4289: 4268: 4263: 4262: 4243: 4242: 4218: 4213: 4212: 4185: 4180: 4179: 4158: 4153: 4152: 4133: 4132: 4131:Finally, since 4110: 4109: 4090: 4089: 4068: 4063: 4062: 4034: 4033: 4012: 4001: 4000: 3979: 3974: 3973: 3952: 3941: 3940: 3921: 3920: 3901: 3900: 3872: 3871: 3846: 3845: 3826: 3825: 3797: 3796: 3768: 3767: 3733: 3732: 3707: 3706: 3666: 3665: 3646: 3645: 3617: 3616: 3582: 3581: 3547: 3546: 3525: 3520: 3519: 3500: 3499: 3474: 3473: 3454: 3453: 3434: 3433: 3414: 3413: 3376: 3375: 3350: 3349: 3328: 3323: 3322: 3303: 3302: 3283: 3282: 3263: 3262: 3243: 3242: 3223: 3222: 3201: 3196: 3195: 3174: 3169: 3168: 3149: 3148: 3123: 3122: 3097: 3096: 3075: 3070: 3069: 3050: 3049: 3027: 3022: 3021: 3000: 2999: 2978: 2973: 2972: 2948: 2943: 2942: 2921: 2916: 2915: 2896: 2895: 2872: 2871: 2843: 2842: 2823: 2822: 2803: 2802: 2780: 2779: 2754: 2749: 2748: 2726: 2725: 2704: 2699: 2698: 2672: 2667: 2666: 2639: 2638: 2619: 2618: 2597: 2592: 2591: 2554: 2553: 2534: 2533: 2499: 2498: 2479: 2478: 2445: 2410: 2409: 2372: 2371: 2344: 2339: 2338: 2319: 2318: 2287: 2286: 2255: 2254: 2233: 2228: 2227: 2202: 2201: 2179: 2178: 2146: 2145: 2111: 2110: 2054: 2053: 2031: 2030: 2007: 2006: 1987: 1986: 1967: 1966: 1947: 1946: 1927: 1926: 1907: 1906: 1899:axiom of choice 1891: 1867: 1866: 1847: 1846: 1827: 1826: 1807: 1806: 1787: 1786: 1767: 1766: 1747: 1746: 1727: 1726: 1705: 1704: 1685: 1684: 1653: 1652: 1633: 1632: 1613: 1612: 1593: 1592: 1573: 1572: 1547: 1546: 1527: 1526: 1507: 1506: 1487: 1486: 1467: 1466: 1447: 1446: 1421: 1420: 1395: 1394: 1375: 1374: 1349: 1348: 1329: 1328: 1309: 1308: 1289: 1288: 1269: 1268: 1249: 1248: 1215: 1204: 1203: 1184: 1183: 1164: 1163: 1157: 1129: 1124: 1123: 1100: 1095: 1094: 1092: 1088: 1084: 1080: 1076: 1072: 1068: 1064: 1039: 1034: 1033: 1031: 1027: 1023: 1019: 1004:. Suppose that 990: 967: 966: 941: 940: 915: 914: 880: 879: 860: 859: 813: 812: 787: 786: 767: 766: 747: 746: 727: 726: 707: 706: 687: 686: 664: 663: 644: 639: 638: 619: 614: 613: 590: 589: 570: 565: 564: 545: 544: 525: 524: 505: 504: 485: 484: 465: 460: 459: 438: 433: 432: 413: 412: 393: 392: 373: 368: 367: 348: 347: 328: 323: 322: 303: 298: 297: 278: 273: 272: 253: 252: 231: 226: 225: 206: 205: 186: 181: 180: 155: 154: 135: 134: 128:totally ordered 106: 101: 100: 81: 80: 74: 54:axiom of choice 41:totally ordered 33:Felix Hausdorff 17: 12: 11: 5: 5384: 5382: 5374: 5373: 5368: 5363: 5353: 5352: 5346: 5345: 5343: 5342: 5337: 5332: 5331: 5330: 5320: 5319: 5318: 5313: 5308: 5298: 5297: 5296: 5286: 5281: 5280: 5279: 5274: 5267:Order morphism 5264: 5263: 5262: 5252: 5247: 5242: 5237: 5232: 5231: 5230: 5220: 5215: 5210: 5204: 5202: 5198: 5197: 5195: 5194: 5193: 5192: 5187: 5185:Locally convex 5182: 5177: 5167: 5165:Order topology 5162: 5161: 5160: 5158:Order topology 5155: 5145: 5135: 5133: 5126: 5125: 5123: 5122: 5117: 5112: 5107: 5102: 5097: 5092: 5087: 5082: 5077: 5071: 5069: 5065: 5064: 5062: 5061: 5051: 5041: 5036: 5031: 5026: 5021: 5016: 5011: 5006: 5005: 5004: 4994: 4989: 4988: 4987: 4982: 4977: 4972: 4970:Chain-complete 4962: 4957: 4956: 4955: 4950: 4945: 4940: 4935: 4925: 4920: 4915: 4910: 4905: 4895: 4890: 4885: 4880: 4875: 4870: 4869: 4868: 4858: 4853: 4847: 4845: 4835: 4834: 4832: 4831: 4826: 4821: 4816: 4811: 4806: 4801: 4796: 4791: 4786: 4781: 4776: 4770: 4768: 4764: 4763: 4761: 4760: 4755: 4750: 4745: 4740: 4735: 4730: 4725: 4719: 4717: 4713: 4712: 4710: 4709: 4704: 4699: 4693: 4690: 4689: 4684: 4682: 4681: 4674: 4667: 4659: 4653: 4652: 4646: 4629: 4619: 4612: 4602: 4579: 4576: 4573: 4572: 4560: 4548: 4535: 4534: 4532: 4529: 4517: 4497: 4494: 4488: 4485: 4462: 4459: 4453: 4450: 4425: 4421: 4400: 4378: 4374: 4350: 4347: 4322: 4318: 4297: 4275: 4271: 4250: 4225: 4221: 4211:, which means 4200: 4197: 4192: 4188: 4165: 4161: 4140: 4117: 4097: 4088:; i.e., is in 4075: 4071: 4047: 4044: 4019: 4015: 4011: 4008: 3986: 3982: 3959: 3955: 3951: 3948: 3928: 3908: 3885: 3882: 3859: 3856: 3853: 3833: 3810: 3807: 3781: 3778: 3752: 3749: 3743: 3740: 3720: 3717: 3714: 3691: 3688: 3682: 3679: 3676: 3673: 3653: 3630: 3627: 3601: 3598: 3592: 3589: 3569: 3566: 3560: 3557: 3532: 3528: 3507: 3487: 3484: 3481: 3461: 3441: 3421: 3398: 3395: 3389: 3386: 3363: 3360: 3357: 3335: 3331: 3310: 3290: 3270: 3250: 3230: 3208: 3204: 3181: 3177: 3156: 3136: 3133: 3130: 3110: 3107: 3104: 3082: 3078: 3057: 3034: 3030: 3020:comparable in 3007: 2985: 2981: 2955: 2951: 2928: 2924: 2903: 2892: 2891: 2879: 2856: 2853: 2830: 2810: 2799: 2787: 2767: 2764: 2760: 2757: 2745: 2733: 2711: 2707: 2679: 2675: 2652: 2649: 2646: 2626: 2604: 2600: 2576: 2573: 2567: 2564: 2541: 2521: 2518: 2512: 2509: 2486: 2475: 2474: 2463: 2460: 2457: 2452: 2448: 2444: 2441: 2438: 2435: 2432: 2429: 2423: 2420: 2394: 2391: 2385: 2382: 2359: 2356: 2351: 2347: 2326: 2306: 2303: 2300: 2297: 2294: 2274: 2271: 2268: 2265: 2262: 2240: 2236: 2215: 2212: 2209: 2186: 2166: 2163: 2160: 2155: 2133: 2130: 2127: 2124: 2121: 2118: 2098: 2095: 2092: 2089: 2086: 2083: 2080: 2077: 2074: 2069: 2064: 2061: 2038: 2027: 2026: 2014: 1994: 1974: 1954: 1934: 1914: 1890: 1887: 1874: 1854: 1834: 1814: 1794: 1785:is a chain in 1774: 1754: 1734: 1712: 1692: 1672: 1669: 1666: 1663: 1660: 1640: 1620: 1600: 1580: 1560: 1557: 1554: 1545:). Second, if 1534: 1514: 1494: 1474: 1454: 1434: 1431: 1428: 1408: 1405: 1402: 1393:, then either 1382: 1362: 1359: 1356: 1336: 1316: 1296: 1276: 1256: 1233: 1230: 1227: 1222: 1218: 1214: 1211: 1191: 1171: 1156: 1153: 1138: 1133: 1109: 1104: 1090: 1086: 1082: 1078: 1074: 1070: 1066: 1062: 1048: 1043: 1029: 1025: 1021: 1017: 989: 986: 974: 954: 951: 948: 928: 925: 922: 902: 899: 893: 890: 867: 847: 844: 841: 838: 835: 832: 826: 823: 800: 797: 794: 774: 754: 734: 714: 694: 671: 650: 647: 625: 622: 597: 576: 573: 552: 532: 512: 492: 471: 468: 445: 441: 420: 400: 379: 376: 355: 334: 331: 309: 306: 284: 281: 260: 238: 234: 213: 192: 189: 162: 142: 113: 109: 99:, every chain 88: 73: 70: 15: 13: 10: 9: 6: 4: 3: 2: 5383: 5372: 5369: 5367: 5364: 5362: 5359: 5358: 5356: 5341: 5338: 5336: 5333: 5329: 5326: 5325: 5324: 5321: 5317: 5314: 5312: 5309: 5307: 5304: 5303: 5302: 5299: 5295: 5292: 5291: 5290: 5289:Ordered field 5287: 5285: 5282: 5278: 5275: 5273: 5270: 5269: 5268: 5265: 5261: 5258: 5257: 5256: 5253: 5251: 5248: 5246: 5245:Hasse diagram 5243: 5241: 5238: 5236: 5233: 5229: 5226: 5225: 5224: 5223:Comparability 5221: 5219: 5216: 5214: 5211: 5209: 5206: 5205: 5203: 5199: 5191: 5188: 5186: 5183: 5181: 5178: 5176: 5173: 5172: 5171: 5168: 5166: 5163: 5159: 5156: 5154: 5151: 5150: 5149: 5146: 5144: 5140: 5137: 5136: 5134: 5131: 5127: 5121: 5118: 5116: 5113: 5111: 5108: 5106: 5103: 5101: 5098: 5096: 5095:Product order 5093: 5091: 5088: 5086: 5083: 5081: 5078: 5076: 5073: 5072: 5070: 5068:Constructions 5066: 5060: 5056: 5052: 5049: 5045: 5042: 5040: 5037: 5035: 5032: 5030: 5027: 5025: 5022: 5020: 5017: 5015: 5012: 5010: 5007: 5003: 5000: 4999: 4998: 4995: 4993: 4990: 4986: 4983: 4981: 4978: 4976: 4973: 4971: 4968: 4967: 4966: 4965:Partial order 4963: 4961: 4958: 4954: 4953:Join and meet 4951: 4949: 4946: 4944: 4941: 4939: 4936: 4934: 4931: 4930: 4929: 4926: 4924: 4921: 4919: 4916: 4914: 4911: 4909: 4906: 4904: 4900: 4896: 4894: 4891: 4889: 4886: 4884: 4881: 4879: 4876: 4874: 4871: 4867: 4864: 4863: 4862: 4859: 4857: 4854: 4852: 4851:Antisymmetric 4849: 4848: 4846: 4842: 4836: 4830: 4827: 4825: 4822: 4820: 4817: 4815: 4812: 4810: 4807: 4805: 4802: 4800: 4797: 4795: 4792: 4790: 4787: 4785: 4782: 4780: 4777: 4775: 4772: 4771: 4769: 4765: 4759: 4758:Weak ordering 4756: 4754: 4751: 4749: 4746: 4744: 4743:Partial order 4741: 4739: 4736: 4734: 4731: 4729: 4726: 4724: 4721: 4720: 4718: 4714: 4708: 4705: 4703: 4700: 4698: 4695: 4694: 4691: 4687: 4680: 4675: 4673: 4668: 4666: 4661: 4660: 4657: 4649: 4643: 4639: 4635: 4634:Rudin, Walter 4630: 4627: 4623: 4622:James Munkres 4620: 4617: 4613: 4610: 4606: 4603: 4600: 4599:0-387-90092-6 4596: 4590: 4586: 4582: 4581: 4577: 4569: 4564: 4561: 4557: 4552: 4549: 4545: 4540: 4537: 4530: 4528: 4515: 4495: 4492: 4486: 4483: 4460: 4457: 4451: 4448: 4423: 4419: 4398: 4376: 4372: 4348: 4345: 4320: 4316: 4295: 4273: 4269: 4248: 4239: 4223: 4219: 4195: 4190: 4186: 4163: 4159: 4129: 4073: 4069: 4045: 4042: 4017: 4013: 4009: 4006: 3984: 3980: 3957: 3953: 3949: 3946: 3926: 3906: 3883: 3880: 3857: 3854: 3851: 3831: 3808: 3805: 3779: 3776: 3750: 3747: 3741: 3738: 3718: 3715: 3712: 3689: 3686: 3680: 3677: 3674: 3671: 3651: 3628: 3625: 3599: 3596: 3590: 3587: 3567: 3564: 3558: 3555: 3530: 3526: 3505: 3498:, then since 3485: 3482: 3479: 3459: 3439: 3419: 3410: 3396: 3393: 3387: 3384: 3361: 3358: 3355: 3333: 3329: 3308: 3288: 3248: 3206: 3202: 3179: 3175: 3134: 3131: 3128: 3108: 3105: 3102: 3080: 3076: 3055: 3047: 3032: 3028: 3005: 2983: 2979: 2969: 2953: 2949: 2926: 2922: 2901: 2877: 2854: 2851: 2828: 2808: 2800: 2785: 2765: 2762: 2758: 2755: 2746: 2731: 2709: 2705: 2697: 2696: 2695: 2693: 2677: 2673: 2650: 2647: 2644: 2624: 2602: 2598: 2588: 2574: 2571: 2565: 2562: 2539: 2519: 2516: 2510: 2507: 2484: 2461: 2450: 2446: 2439: 2433: 2430: 2427: 2421: 2418: 2408: 2407: 2406: 2392: 2389: 2383: 2380: 2354: 2349: 2345: 2324: 2301: 2295: 2292: 2272: 2269: 2266: 2263: 2260: 2238: 2234: 2213: 2210: 2207: 2198: 2184: 2161: 2131: 2128: 2122: 2116: 2096: 2081: 2075: 2062: 2059: 2050: 2036: 2012: 1992: 1972: 1952: 1932: 1912: 1904: 1903: 1902: 1900: 1896: 1888: 1886: 1872: 1852: 1832: 1812: 1792: 1772: 1752: 1732: 1723: 1710: 1690: 1667: 1661: 1658: 1638: 1631:cannot be in 1618: 1598: 1578: 1558: 1555: 1552: 1532: 1512: 1492: 1472: 1452: 1432: 1429: 1426: 1406: 1403: 1400: 1380: 1360: 1357: 1354: 1334: 1314: 1294: 1274: 1254: 1245: 1228: 1220: 1216: 1212: 1209: 1189: 1169: 1162: 1161:Hilbert space 1154: 1152: 1136: 1107: 1046: 1014: 1011: 1007: 1003: 999: 995: 987: 985: 972: 952: 949: 946: 926: 923: 920: 900: 897: 891: 888: 865: 842: 836: 833: 830: 824: 821: 798: 795: 792: 772: 752: 732: 712: 692: 683: 669: 648: 645: 623: 620: 609: 595: 574: 571: 550: 530: 510: 490: 469: 466: 443: 439: 418: 398: 377: 374: 353: 332: 329: 307: 304: 282: 279: 258: 236: 232: 211: 190: 187: 177: 174: 160: 140: 132: 129: 111: 107: 86: 79: 71: 69: 67: 63: 59: 55: 50: 47: 45: 42: 38: 34: 30: 26: 22: 5371:Order theory 5132:& Orders 5110:Star product 5039:Well-founded 4992:Prefix order 4948:Distributive 4938:Complemented 4908:Foundational 4873:Completeness 4829:Zorn's lemma 4798: 4733:Cyclic order 4716:Key concepts 4686:Order theory 4637: 4631:Appendix of 4625: 4615: 4608: 4588: 4585:Halmos, Paul 4563: 4551: 4539: 4240: 4130: 4128:is a tower. 3411: 3048:if for each 3019: 2970: 2893: 2665:tower (over 2664: 2589: 2476: 2199: 2051: 2028: 1895:Zorn's lemma 1892: 1724: 1246: 1158: 1015: 1009: 1005: 1001: 993: 991: 684: 610: 543:is a union, 178: 175: 75: 65: 61: 51: 48: 29:Zorn's lemma 24: 18: 5316:Riesz space 5277:Isomorphism 5153:Normal cone 5075:Composition 5009:Semilattice 4918:Homogeneous 4903:Equivalence 4753:Total order 4618:, Springer. 4605:John Kelley 4556:Halmos 1960 3221:. We claim 2914:containing 2370:, then let 1897:, from the 1155:Application 1061:, define (x 21:mathematics 5355:Categories 5284:Order type 5218:Cofinality 5059:Well-order 5034:Transitive 4923:Idempotent 4856:Asymmetric 4628:, Pearson. 4578:References 4570:, Appendix 4568:Rudin 1986 4544:Rudin 1986 4178:, we have 2552:such that 2285:such that 2109:such that 31:proved by 5335:Upper set 5272:Embedding 5208:Antichain 5029:Tolerance 5019:Symmetric 5014:Semiorder 4960:Reflexive 4878:Connected 4516:◻ 4487:~ 4473:and thus 4458:⊂ 4452:~ 4349:~ 4288:. By 2., 4199:Γ 4139:Γ 4116:Γ 4096:Γ 4046:~ 3950:⊂ 3919:. Hence, 3884:~ 3870:, we see 3855:⊂ 3809:~ 3780:~ 3751:~ 3690:~ 3681:⊂ 3675:⊂ 3629:~ 3600:~ 3591:⊂ 3565:⊂ 3559:~ 3545:, either 3483:⊂ 3412:We claim 3394:⊂ 3388:~ 3359:⊂ 3269:Γ 3229:Γ 3155:Γ 3132:⊂ 3106:⊂ 3095:, either 2855:~ 2801:For each 2763:⊂ 2648:⊂ 2566:~ 2511:~ 2451:∗ 2434:∪ 2422:~ 2384:~ 2358:∅ 2350:∗ 2296:∪ 2270:− 2264:∈ 2239:∗ 2211:∈ 2200:For each 2129:∈ 2094:→ 2088:∅ 2082:− 1711:◻ 1662:∪ 1571:for some 1556:⊋ 1430:⊂ 1404:⊂ 1217:ℓ 1213:≃ 1069:) < (x 973:◻ 924:∈ 892:~ 837:∪ 825:~ 796:≥ 637:and thus 431:contains 126:(i.e., a 72:Statement 56:over ZF ( 5130:Topology 4997:Preorder 4980:Eulerian 4943:Complete 4893:Directed 4883:Covering 4748:Preorder 4707:Category 4702:Glossary 4636:(1986). 4626:Topology 4624:(2000), 4607:(1955), 4587:(1960). 4391:. Since 2759:′ 1024:) and (x 988:Examples 913:; i.e., 649:′ 624:′ 575:′ 470:′ 378:′ 333:′ 308:′ 283:′ 191:′ 39:, every 5235:Duality 5213:Cofinal 5201:Related 5180:FrĂ©chet 5057:)  4933:Bounded 4928:Lattice 4901:)  4899:Partial 4767:Results 4738:Lattice 4558:, § 16. 2005:. Then 1651:and so 1611:, then 1373:are in 939:and so 811:, then 271:. Then 64:or the 5260:Subnet 5240:Filter 5190:Normed 5175:Banach 5141:& 5048:Better 4985:Strict 4975:Graded 4866:topics 4697:Topics 4644:  4597:  4364:is in 4308:is in 3899:is in 3824:is in 3644:is in 3452:be in 3147:. Let 2870:is in 2778:is in 2724:is in 2590:Fix a 2317:is in 2226:, let 1985:is in 1945:is in 1307:. Let 1089:< x 1077:) if y 346:. Let 131:subset 44:subset 23:, the 5250:Ideal 5228:Graph 5024:Total 5002:Total 4888:Dense 4531:Notes 3472:. If 2477:Note 2337:. If 1889:Proof 1765:. If 1085:and x 1016:If (x 785:. If 4841:list 4642:ISBN 4595:ISBN 4241:Let 3972:and 1905:Let 1247:Let 5255:Net 5055:Pre 3731:or 3580:or 3374:or 3321:in 3261:in 3121:or 3068:in 3018:is 2821:in 2694:if 2617:in 2177:of 1591:in 1485:in 1419:or 1081:= y 1073:, y 1065:, y 1028:, y 1020:, y 1000:on 992:If 765:in 523:as 251:in 19:In 5357:: 4508:. 4438:, 3409:. 2841:, 2663:a 2587:. 2197:. 1901:. 1151:. 965:. 682:. 608:. 5053:( 5050:) 5046:( 4897:( 4844:) 4678:e 4671:t 4664:v 4650:. 4496:C 4493:= 4484:C 4461:C 4449:C 4424:0 4420:T 4399:C 4377:0 4373:T 4346:C 4321:0 4317:T 4296:C 4274:0 4270:T 4249:C 4224:0 4220:T 4196:= 4191:0 4187:T 4164:0 4160:T 4074:0 4070:T 4043:C 4018:0 4014:T 4010:= 4007:U 3985:0 3981:T 3958:0 3954:T 3947:U 3927:U 3907:U 3881:A 3858:A 3852:C 3832:U 3806:A 3777:A 3748:A 3742:= 3739:C 3719:C 3716:= 3713:A 3687:A 3678:C 3672:A 3652:U 3626:A 3597:A 3588:C 3568:C 3556:A 3531:0 3527:T 3506:C 3486:C 3480:A 3460:U 3440:A 3420:U 3397:A 3385:C 3362:C 3356:A 3334:0 3330:T 3309:A 3289:U 3249:C 3207:0 3203:T 3180:0 3176:T 3135:A 3129:C 3109:C 3103:A 3081:0 3077:T 3056:A 3033:0 3029:T 3006:C 2984:0 2980:T 2954:0 2950:T 2927:0 2923:C 2902:F 2890:. 2878:T 2852:C 2829:T 2809:C 2786:T 2766:T 2756:T 2744:. 2732:T 2710:0 2706:C 2692:) 2678:0 2674:C 2651:F 2645:T 2625:F 2603:0 2599:C 2575:C 2572:= 2563:C 2540:C 2520:C 2517:= 2508:C 2485:C 2462:. 2459:} 2456:) 2447:C 2443:( 2440:f 2437:{ 2431:C 2428:= 2419:C 2393:C 2390:= 2381:C 2355:= 2346:C 2325:F 2305:} 2302:x 2299:{ 2293:C 2273:C 2267:P 2261:x 2235:C 2214:F 2208:C 2185:P 2165:) 2162:P 2159:( 2154:P 2132:S 2126:) 2123:S 2120:( 2117:f 2097:P 2091:} 2085:{ 2079:) 2076:P 2073:( 2068:P 2063:: 2060:f 2037:P 2013:F 1993:F 1973:F 1953:F 1933:F 1913:F 1873:A 1853:P 1833:Q 1813:Q 1793:P 1773:Q 1753:H 1733:P 1691:Q 1671:} 1668:B 1665:{ 1659:Q 1639:Q 1619:B 1599:P 1579:B 1559:A 1553:B 1533:H 1513:A 1493:Q 1473:S 1453:A 1433:S 1427:T 1407:T 1401:S 1381:Q 1361:T 1358:, 1355:S 1335:Q 1315:A 1295:Q 1275:H 1255:P 1232:) 1229:A 1226:( 1221:2 1210:H 1190:A 1170:H 1137:2 1132:R 1108:2 1103:R 1091:1 1087:0 1083:1 1079:0 1075:1 1071:1 1067:0 1063:0 1047:2 1042:R 1030:1 1026:1 1022:0 1018:0 1010:A 1006:A 1002:A 994:A 953:x 950:= 947:y 927:C 921:y 901:C 898:= 889:C 866:C 846:} 843:y 840:{ 834:C 831:= 822:C 799:x 793:y 773:P 753:x 733:C 713:C 693:P 670:P 646:P 621:P 596:P 572:P 551:C 531:C 511:C 491:C 467:P 444:0 440:C 419:C 399:P 375:C 354:C 330:C 305:P 280:P 259:P 237:0 233:C 212:P 188:P 161:P 141:C 112:0 108:C 87:P

Index

mathematics
Zorn's lemma
Felix Hausdorff
partially ordered set
totally ordered
subset
axiom of choice
Zermelo–Fraenkel set theory
partially ordered set
totally ordered
subset
strict partial order
Hilbert space
Zorn's lemma
axiom of choice
Rudin 1986
Halmos 1960
Rudin 1986
Halmos, Paul
ISBN
0-387-90092-6
John Kelley
James Munkres
Rudin, Walter
ISBN
978-0-07-054234-1
v
t
e
Order theory

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