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Extension by new constant and function names

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Shoenfield states the theorem in the form for a new function name, and constants are the same as functions of zero arguments. In formal systems that admit ordered tuples, extension by multiple constants as shown here can be accomplished by addition of a new constant tuple and the new constant names
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is perhaps the best-known approach, but it requires unique existence of an object with the desired property. Addition of new names can also be done safely without uniqueness.
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can be extended with new constants or function names under certain conditions with assurance that the extension will introduce no contradiction.
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has the same set of theorems in the original language (i.e., without constants
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Such a theory can also be conservatively extended by introducing a new
770:{\displaystyle \forall {\vec {x}}\,\varphi (f({\vec {x}}),{\vec {x}})} 2676: 2579: 1632: 1549: 1509: 1473: 1409: 1221: 1211: 1184: 947: 2661: 2459: 1907: 1612: 1206: 2257: 1049: 2711: 2768: 2719: 1801: 1147: 992: 253: 875:
prove the same theorems not involving the functional symbol
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by extending its language with a new functional symbol
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You can help Knowledge by 2575:Primitive recursive function 7: 902: 10: 2866: 2762: 2705: 1639:Schröder–Bernstein theorem 1366:Monadic predicate calculus 1025:Foundations of mathematics 639:be a theory obtained from 176:be a theory obtained from 2685: 2672:Philosophy of mathematics 2621:Automated theorem proving 2603: 2498: 2330: 2223: 2075: 1792: 1768: 1746:Von Neumann–Bernays–Gödel 1691: 1585: 1489: 1387: 1378: 1305: 1240: 1146: 1068: 985: 699:) and adding a new axiom 2835:Mathematical logic stubs 26:Extension by definitions 2322:Self-verifying theories 2143:Tarski's axiomatization 1094:Tarski's undefinability 1089:incompleteness theorems 914:Extension by definition 2779:-related article is a 2722:-related article is a 2696:Mathematics portal 2307:Proof of impossibility 1955:propositional variable 1265:Propositional calculus 909:Conservative extension 889: 869: 842: 822: 806:conservative extension 798: 771: 693: 673: 653: 633: 606: 539: 519: 436: 416: 389: 362: 346:conservative extension 338: 307: 243: 190: 170: 143: 117: 2565:Kolmogorov complexity 2518:Computably enumerable 2418:Model complete theory 2210:Principia Mathematica 1270:Propositional formula 1099:Banach–Tarski paradox 890: 870: 868:{\displaystyle T_{1}} 843: 823: 799: 797:{\displaystyle T_{1}} 772: 694: 674: 654: 634: 632:{\displaystyle T_{1}} 607: 540: 520: 437: 417: 415:{\displaystyle a_{i}} 390: 388:{\displaystyle T_{1}} 363: 339: 337:{\displaystyle T_{1}} 308: 244: 191: 171: 169:{\displaystyle T_{1}} 144: 118: 2513:Church–Turing thesis 2500:Computability theory 1709:continuum hypothesis 1227:Square of opposition 1085:Gödel's completeness 879: 852: 832: 828:, i.e. the theories 812: 781: 703: 683: 663: 643: 616: 549: 529: 460: 426: 399: 372: 352: 321: 262: 207: 200:with new constants 180: 153: 133: 42: 2667:Mathematical object 2558:P versus NP problem 2523:Computable function 2317:Reverse mathematics 2243:Logical consequence 2120:primitive recursive 2115:elementary function 1888:Free/bound variable 1741:Tarski–Grothendieck 1260:Logical connectives 1190:Logical equivalence 1040:Logical consequence 2840:Mathematical logic 2777:mathematical logic 2465:Transfer principle 2428:Semantics of logic 2413:Categorical theory 2389:Non-standard model 1903:Logical connective 1030:Information theory 979:Mathematical logic 938:Mathematical Logic 934:Shoenfield, Joseph 885: 865: 838: 818: 794: 767: 689: 669: 649: 629: 602: 545:, where we denote 535: 515: 432: 412: 385: 358: 334: 303: 239: 186: 166: 139: 128:first-order theory 126:is a theorem of a 113: 18:mathematical logic 2792: 2791: 2735: 2734: 2703: 2702: 2635:Abstract category 2438:Theories of truth 2248:Rule of inference 2238:Natural deduction 2219: 2218: 1764: 1763: 1469:Cartesian product 1374: 1373: 1280:Many-valued logic 1255:Boolean functions 1138:Russell's paradox 1113:diagonal argument 1010:First-order logic 888:{\displaystyle f} 841:{\displaystyle T} 821:{\displaystyle T} 761: 743: 718: 692:{\displaystyle n} 672:{\displaystyle f} 652:{\displaystyle T} 561: 538:{\displaystyle T} 509: 475: 447:functional symbol 435:{\displaystyle T} 361:{\displaystyle T} 252:and adding a new 196:by extending its 189:{\displaystyle T} 142:{\displaystyle T} 2857: 2813: 2806: 2799: 2771: 2764: 2756: 2749: 2742: 2714: 2707: 2694: 2693: 2645:History of logic 2640:Category of sets 2533:Decision problem 2312:Ordinal analysis 2253:Sequent calculus 2151:Boolean algebras 2091: 2090: 2065: 2036:logical/constant 1790: 1789: 1776: 1699:Zermelo–Fraenkel 1450:Set operations: 1385: 1384: 1322: 1153: 1152: 1133:Löwenheim–Skolem 1020:Formal semantics 972: 965: 958: 949: 948: 942: 941: 930: 894: 892: 891: 886: 874: 872: 871: 866: 864: 863: 847: 845: 844: 839: 827: 825: 824: 819: 803: 801: 800: 795: 793: 792: 776: 774: 773: 768: 763: 762: 754: 745: 744: 736: 720: 719: 711: 698: 696: 695: 690: 678: 676: 675: 670: 658: 656: 655: 650: 638: 636: 635: 630: 628: 627: 611: 609: 608: 603: 598: 597: 579: 578: 563: 562: 554: 544: 542: 541: 536: 524: 522: 521: 516: 511: 510: 502: 477: 476: 468: 441: 439: 438: 433: 422:) as the theory 421: 419: 418: 413: 411: 410: 394: 392: 391: 386: 384: 383: 367: 365: 364: 359: 343: 341: 340: 335: 333: 332: 312: 310: 309: 304: 299: 298: 280: 279: 248: 246: 245: 240: 238: 237: 219: 218: 195: 193: 192: 187: 175: 173: 172: 167: 165: 164: 148: 146: 145: 140: 122: 120: 119: 114: 109: 108: 90: 89: 73: 72: 57: 56: 2865: 2864: 2860: 2859: 2858: 2856: 2855: 2854: 2820: 2819: 2818: 2817: 2761: 2760: 2704: 2699: 2688: 2681: 2626:Category theory 2616:Algebraic logic 2599: 2570:Lambda calculus 2508:Church encoding 2494: 2470:Truth predicate 2326: 2292:Complete theory 2215: 2084: 2080: 2076: 2071: 2063: 1783: and  1779: 1774: 1760: 1736:New Foundations 1704:axiom of choice 1687: 1649:Gödel numbering 1589: and  1581: 1485: 1370: 1320: 1301: 1250:Boolean algebra 1236: 1200:Equiconsistency 1165:Classical logic 1142: 1123:Halting problem 1111: and  1087: and  1075: and  1074: 1069:Theorems ( 1064: 981: 976: 946: 945: 931: 927: 922: 905: 880: 877: 876: 859: 855: 853: 850: 849: 833: 830: 829: 813: 810: 809: 788: 784: 782: 779: 778: 753: 752: 735: 734: 710: 709: 704: 701: 700: 684: 681: 680: 664: 661: 660: 644: 641: 640: 623: 619: 617: 614: 613: 593: 589: 574: 570: 553: 552: 550: 547: 546: 530: 527: 526: 501: 500: 467: 466: 461: 458: 457: 452:Suppose that a 427: 424: 423: 406: 402: 400: 397: 396: 379: 375: 373: 370: 369: 353: 350: 349: 328: 324: 322: 319: 318: 294: 290: 275: 271: 263: 260: 259: 233: 229: 214: 210: 208: 205: 204: 181: 178: 177: 160: 156: 154: 151: 150: 134: 131: 130: 104: 100: 85: 81: 68: 64: 52: 48: 43: 40: 39: 31:Suppose that a 12: 11: 5: 2863: 2853: 2852: 2847: 2842: 2837: 2832: 2816: 2815: 2808: 2801: 2793: 2790: 2789: 2772: 2759: 2758: 2751: 2744: 2736: 2733: 2732: 2715: 2701: 2700: 2686: 2683: 2682: 2680: 2679: 2674: 2669: 2664: 2659: 2658: 2657: 2647: 2642: 2637: 2628: 2623: 2618: 2613: 2611:Abstract logic 2607: 2605: 2601: 2600: 2598: 2597: 2592: 2590:Turing machine 2587: 2582: 2577: 2572: 2567: 2562: 2561: 2560: 2555: 2550: 2545: 2540: 2530: 2528:Computable set 2525: 2520: 2515: 2510: 2504: 2502: 2496: 2495: 2493: 2492: 2487: 2482: 2477: 2472: 2467: 2462: 2457: 2456: 2455: 2450: 2445: 2435: 2430: 2425: 2423:Satisfiability 2420: 2415: 2410: 2409: 2408: 2398: 2397: 2396: 2386: 2385: 2384: 2379: 2374: 2369: 2364: 2354: 2353: 2352: 2347: 2340:Interpretation 2336: 2334: 2328: 2327: 2325: 2324: 2319: 2314: 2309: 2304: 2294: 2289: 2288: 2287: 2286: 2285: 2275: 2270: 2260: 2255: 2250: 2245: 2240: 2235: 2229: 2227: 2221: 2220: 2217: 2216: 2214: 2213: 2205: 2204: 2203: 2202: 2197: 2196: 2195: 2190: 2185: 2165: 2164: 2163: 2161:minimal axioms 2158: 2147: 2146: 2145: 2134: 2133: 2132: 2127: 2122: 2117: 2112: 2107: 2094: 2092: 2073: 2072: 2070: 2069: 2068: 2067: 2055: 2050: 2049: 2048: 2043: 2038: 2033: 2023: 2018: 2013: 2008: 2007: 2006: 2001: 1991: 1990: 1989: 1984: 1979: 1974: 1964: 1959: 1958: 1957: 1952: 1947: 1937: 1936: 1935: 1930: 1925: 1920: 1915: 1910: 1900: 1895: 1890: 1885: 1884: 1883: 1878: 1873: 1868: 1858: 1853: 1851:Formation rule 1848: 1843: 1842: 1841: 1836: 1826: 1825: 1824: 1814: 1809: 1804: 1799: 1793: 1787: 1770:Formal systems 1766: 1765: 1762: 1761: 1759: 1758: 1753: 1748: 1743: 1738: 1733: 1728: 1723: 1718: 1713: 1712: 1711: 1706: 1695: 1693: 1689: 1688: 1686: 1685: 1684: 1683: 1673: 1668: 1667: 1666: 1659:Large cardinal 1656: 1651: 1646: 1641: 1636: 1622: 1621: 1620: 1615: 1610: 1595: 1593: 1583: 1582: 1580: 1579: 1578: 1577: 1572: 1567: 1557: 1552: 1547: 1542: 1537: 1532: 1527: 1522: 1517: 1512: 1507: 1502: 1496: 1494: 1487: 1486: 1484: 1483: 1482: 1481: 1476: 1471: 1466: 1461: 1456: 1448: 1447: 1446: 1441: 1431: 1426: 1424:Extensionality 1421: 1419:Ordinal number 1416: 1406: 1401: 1400: 1399: 1388: 1382: 1376: 1375: 1372: 1371: 1369: 1368: 1363: 1358: 1353: 1348: 1343: 1338: 1337: 1336: 1326: 1325: 1324: 1311: 1309: 1303: 1302: 1300: 1299: 1298: 1297: 1292: 1287: 1277: 1272: 1267: 1262: 1257: 1252: 1246: 1244: 1238: 1237: 1235: 1234: 1229: 1224: 1219: 1214: 1209: 1204: 1203: 1202: 1192: 1187: 1182: 1177: 1172: 1167: 1161: 1159: 1150: 1144: 1143: 1141: 1140: 1135: 1130: 1125: 1120: 1115: 1103:Cantor's  1101: 1096: 1091: 1081: 1079: 1066: 1065: 1063: 1062: 1057: 1052: 1047: 1042: 1037: 1032: 1027: 1022: 1017: 1012: 1007: 1002: 1001: 1000: 989: 987: 983: 982: 975: 974: 967: 960: 952: 944: 943: 924: 923: 921: 918: 917: 916: 911: 904: 901: 884: 862: 858: 837: 817: 791: 787: 766: 760: 757: 751: 748: 742: 739: 733: 730: 727: 724: 717: 714: 708: 688: 668: 648: 626: 622: 601: 596: 592: 588: 585: 582: 577: 573: 569: 566: 560: 557: 534: 514: 508: 505: 499: 496: 493: 490: 484: 481: 474: 471: 465: 431: 409: 405: 382: 378: 357: 331: 327: 315: 314: 302: 297: 293: 289: 286: 283: 278: 274: 270: 267: 250: 249: 236: 232: 228: 225: 222: 217: 213: 185: 163: 159: 138: 124: 123: 112: 107: 103: 99: 96: 93: 88: 84: 80: 77: 71: 67: 63: 60: 55: 51: 47: 9: 6: 4: 3: 2: 2862: 2851: 2848: 2846: 2843: 2841: 2838: 2836: 2833: 2831: 2828: 2827: 2825: 2814: 2809: 2807: 2802: 2800: 2795: 2794: 2788: 2786: 2782: 2778: 2773: 2770: 2766: 2765: 2757: 2752: 2750: 2745: 2743: 2738: 2737: 2731: 2729: 2725: 2721: 2716: 2713: 2709: 2708: 2698: 2697: 2692: 2684: 2678: 2675: 2673: 2670: 2668: 2665: 2663: 2660: 2656: 2653: 2652: 2651: 2648: 2646: 2643: 2641: 2638: 2636: 2632: 2629: 2627: 2624: 2622: 2619: 2617: 2614: 2612: 2609: 2608: 2606: 2602: 2596: 2593: 2591: 2588: 2586: 2585:Recursive set 2583: 2581: 2578: 2576: 2573: 2571: 2568: 2566: 2563: 2559: 2556: 2554: 2551: 2549: 2546: 2544: 2541: 2539: 2536: 2535: 2534: 2531: 2529: 2526: 2524: 2521: 2519: 2516: 2514: 2511: 2509: 2506: 2505: 2503: 2501: 2497: 2491: 2488: 2486: 2483: 2481: 2478: 2476: 2473: 2471: 2468: 2466: 2463: 2461: 2458: 2454: 2451: 2449: 2446: 2444: 2441: 2440: 2439: 2436: 2434: 2431: 2429: 2426: 2424: 2421: 2419: 2416: 2414: 2411: 2407: 2404: 2403: 2402: 2399: 2395: 2394:of arithmetic 2392: 2391: 2390: 2387: 2383: 2380: 2378: 2375: 2373: 2370: 2368: 2365: 2363: 2360: 2359: 2358: 2355: 2351: 2348: 2346: 2343: 2342: 2341: 2338: 2337: 2335: 2333: 2329: 2323: 2320: 2318: 2315: 2313: 2310: 2308: 2305: 2302: 2301:from ZFC 2298: 2295: 2293: 2290: 2284: 2281: 2280: 2279: 2276: 2274: 2271: 2269: 2266: 2265: 2264: 2261: 2259: 2256: 2254: 2251: 2249: 2246: 2244: 2241: 2239: 2236: 2234: 2231: 2230: 2228: 2226: 2222: 2212: 2211: 2207: 2206: 2201: 2200:non-Euclidean 2198: 2194: 2191: 2189: 2186: 2184: 2183: 2179: 2178: 2176: 2173: 2172: 2170: 2166: 2162: 2159: 2157: 2154: 2153: 2152: 2148: 2144: 2141: 2140: 2139: 2135: 2131: 2128: 2126: 2123: 2121: 2118: 2116: 2113: 2111: 2108: 2106: 2103: 2102: 2100: 2096: 2095: 2093: 2088: 2082: 2077:Example  2074: 2066: 2061: 2060: 2059: 2056: 2054: 2051: 2047: 2044: 2042: 2039: 2037: 2034: 2032: 2029: 2028: 2027: 2024: 2022: 2019: 2017: 2014: 2012: 2009: 2005: 2002: 2000: 1997: 1996: 1995: 1992: 1988: 1985: 1983: 1980: 1978: 1975: 1973: 1970: 1969: 1968: 1965: 1963: 1960: 1956: 1953: 1951: 1948: 1946: 1943: 1942: 1941: 1938: 1934: 1931: 1929: 1926: 1924: 1921: 1919: 1916: 1914: 1911: 1909: 1906: 1905: 1904: 1901: 1899: 1896: 1894: 1891: 1889: 1886: 1882: 1879: 1877: 1874: 1872: 1869: 1867: 1864: 1863: 1862: 1859: 1857: 1854: 1852: 1849: 1847: 1844: 1840: 1837: 1835: 1834:by definition 1832: 1831: 1830: 1827: 1823: 1820: 1819: 1818: 1815: 1813: 1810: 1808: 1805: 1803: 1800: 1798: 1795: 1794: 1791: 1788: 1786: 1782: 1777: 1771: 1767: 1757: 1754: 1752: 1749: 1747: 1744: 1742: 1739: 1737: 1734: 1732: 1729: 1727: 1724: 1722: 1721:Kripke–Platek 1719: 1717: 1714: 1710: 1707: 1705: 1702: 1701: 1700: 1697: 1696: 1694: 1690: 1682: 1679: 1678: 1677: 1674: 1672: 1669: 1665: 1662: 1661: 1660: 1657: 1655: 1652: 1650: 1647: 1645: 1642: 1640: 1637: 1634: 1630: 1626: 1623: 1619: 1616: 1614: 1611: 1609: 1606: 1605: 1604: 1600: 1597: 1596: 1594: 1592: 1588: 1584: 1576: 1573: 1571: 1568: 1566: 1565:constructible 1563: 1562: 1561: 1558: 1556: 1553: 1551: 1548: 1546: 1543: 1541: 1538: 1536: 1533: 1531: 1528: 1526: 1523: 1521: 1518: 1516: 1513: 1511: 1508: 1506: 1503: 1501: 1498: 1497: 1495: 1493: 1488: 1480: 1477: 1475: 1472: 1470: 1467: 1465: 1462: 1460: 1457: 1455: 1452: 1451: 1449: 1445: 1442: 1440: 1437: 1436: 1435: 1432: 1430: 1427: 1425: 1422: 1420: 1417: 1415: 1411: 1407: 1405: 1402: 1398: 1395: 1394: 1393: 1390: 1389: 1386: 1383: 1381: 1377: 1367: 1364: 1362: 1359: 1357: 1354: 1352: 1349: 1347: 1344: 1342: 1339: 1335: 1332: 1331: 1330: 1327: 1323: 1318: 1317: 1316: 1313: 1312: 1310: 1308: 1304: 1296: 1293: 1291: 1288: 1286: 1283: 1282: 1281: 1278: 1276: 1273: 1271: 1268: 1266: 1263: 1261: 1258: 1256: 1253: 1251: 1248: 1247: 1245: 1243: 1242:Propositional 1239: 1233: 1230: 1228: 1225: 1223: 1220: 1218: 1215: 1213: 1210: 1208: 1205: 1201: 1198: 1197: 1196: 1193: 1191: 1188: 1186: 1183: 1181: 1178: 1176: 1173: 1171: 1170:Logical truth 1168: 1166: 1163: 1162: 1160: 1158: 1154: 1151: 1149: 1145: 1139: 1136: 1134: 1131: 1129: 1126: 1124: 1121: 1119: 1116: 1114: 1110: 1106: 1102: 1100: 1097: 1095: 1092: 1090: 1086: 1083: 1082: 1080: 1078: 1072: 1067: 1061: 1058: 1056: 1053: 1051: 1048: 1046: 1043: 1041: 1038: 1036: 1033: 1031: 1028: 1026: 1023: 1021: 1018: 1016: 1013: 1011: 1008: 1006: 1003: 999: 996: 995: 994: 991: 990: 988: 984: 980: 973: 968: 966: 961: 959: 954: 953: 950: 939: 935: 929: 925: 915: 912: 910: 907: 906: 900: 896: 882: 860: 856: 835: 815: 807: 789: 785: 755: 749: 737: 728: 722: 712: 686: 666: 646: 624: 620: 594: 590: 586: 583: 580: 575: 571: 564: 555: 532: 503: 497: 494: 488: 482: 469: 455: 450: 448: 443: 429: 407: 403: 380: 376: 355: 347: 329: 325: 295: 291: 287: 284: 281: 276: 272: 265: 258: 257: 256: 255: 234: 230: 226: 223: 220: 215: 211: 203: 202: 201: 199: 183: 161: 157: 136: 129: 105: 101: 97: 94: 91: 86: 82: 75: 69: 65: 58: 53: 49: 38: 37: 36: 34: 29: 27: 23: 19: 2850:Proof theory 2785:expanding it 2774: 2728:expanding it 2717: 2687: 2485:Ultraproduct 2332:Model theory 2297:Independence 2233:Formal proof 2225:Proof theory 2208: 2181: 2138:real numbers 2110:second-order 2021:Substitution 1898:Metalanguage 1839:conservative 1828: 1812:Axiom schema 1756:Constructive 1726:Morse–Kelley 1692:Set theories 1671:Aleph number 1664:inaccessible 1570:Grothendieck 1454:intersection 1341:Higher-order 1329:Second-order 1275:Truth tables 1232:Venn diagram 1015:Formal proof 937: 928: 897: 453: 451: 444: 316: 251: 125: 32: 30: 15: 2830:Logic stubs 2595:Type theory 2543:undecidable 2475:Truth value 2362:equivalence 2041:non-logical 1654:Enumeration 1644:Isomorphism 1591:cardinality 1575:Von Neumann 1540:Ultrafilter 1505:Uncountable 1439:equivalence 1356:Quantifiers 1346:Fixed-point 1315:First-order 1195:Consistency 1180:Proposition 1157:Traditional 1128:Lindström's 1118:Compactness 1060:Type theory 1005:Cardinality 2824:Categories 2406:elementary 2099:arithmetic 1967:Quantifier 1945:functional 1817:Expression 1535:Transitive 1479:identities 1464:complement 1397:hereditary 1380:Set theory 920:References 679:(of arity 2677:Supertask 2580:Recursion 2538:decidable 2372:saturated 2350:of models 2273:deductive 2268:axiomatic 2188:Hilbert's 2175:Euclidean 2156:canonical 2079:axiomatic 2011:Signature 1940:Predicate 1829:Extension 1751:Ackermann 1676:Operation 1555:Universal 1545:Recursive 1520:Singleton 1515:Inhabited 1500:Countable 1490:Types of 1474:power set 1444:partition 1361:Predicate 1307:Predicate 1222:Syllogism 1212:Soundness 1185:Inference 1175:Tautology 1077:paradoxes 759:→ 741:→ 723:φ 716:→ 707:∀ 584:… 559:→ 507:→ 489:φ 480:∃ 473:→ 464:∀ 285:… 266:φ 224:… 95:… 76:φ 62:∃ 59:… 46:∃ 35:formula 2662:Logicism 2655:timeline 2631:Concrete 2490:Validity 2460:T-schema 2453:Kripke's 2448:Tarski's 2443:semantic 2433:Strength 2382:submodel 2377:spectrum 2345:function 2193:Tarski's 2182:Elements 2169:geometry 2125:Robinson 2046:variable 2031:function 2004:spectrum 1994:Sentence 1950:variable 1893:Language 1846:Relation 1807:Automata 1797:Alphabet 1781:language 1635:-jection 1613:codomain 1599:Function 1560:Universe 1530:Infinite 1434:Relation 1217:Validity 1207:Argument 1105:theorem, 936:(1967). 903:See also 456:formula 198:language 2604:Related 2401:Diagram 2299: ( 2278:Hilbert 2263:Systems 2258:Theorem 2136:of the 2081:systems 1861:Formula 1856:Grammar 1772: ( 1716:General 1429:Forcing 1414:Element 1334:Monadic 1109:paradox 1050:Theorem 986:General 777:. Then 2367:finite 2130:Skolem 2083:  2058:Theory 2026:Symbol 2016:String 1999:atomic 1876:ground 1871:closed 1866:atomic 1822:ground 1785:syntax 1681:binary 1608:domain 1525:Finite 1290:finite 1148:Logics 1107:  1055:Theory 612:. Let 454:closed 149:. Let 33:closed 22:theory 2775:This 2720:logic 2718:This 2357:Model 2105:Peano 1962:Proof 1802:Arity 1731:Naive 1618:image 1550:Fuzzy 1510:Empty 1459:union 1404:Class 1045:Model 1035:Lemma 993:Axiom 804:is a 344:is a 317:Then 254:axiom 2781:stub 2724:stub 2480:Type 2283:list 2087:list 2064:list 2053:Term 1987:rank 1881:open 1775:list 1587:Maps 1492:sets 1351:Free 1321:list 1071:list 998:list 848:and 20:, a 2167:of 2149:of 2097:of 1629:Sur 1603:Map 1410:Ur- 1392:Set 895:). 808:of 348:of 16:In 2826:: 2553:NP 2177:: 2171:: 2101:: 1778:), 1633:Bi 1625:In 565::= 449:: 442:. 2812:e 2805:t 2798:v 2787:. 2755:e 2748:t 2741:v 2730:. 2633:/ 2548:P 2303:) 2089:) 2085:( 1982:∀ 1977:! 1972:∃ 1933:= 1928:↔ 1923:→ 1918:∧ 1913:√ 1908:ÂŹ 1631:/ 1627:/ 1601:/ 1412:) 1408:( 1295:∞ 1285:3 1073:) 971:e 964:t 957:v 883:f 861:1 857:T 836:T 816:T 790:1 786:T 765:) 756:x 750:, 747:) 738:x 732:( 729:f 726:( 713:x 687:n 667:f 647:T 625:1 621:T 600:) 595:n 591:x 587:, 581:, 576:1 572:x 568:( 556:x 533:T 513:) 504:x 498:, 495:y 492:( 483:y 470:x 430:T 408:i 404:a 381:1 377:T 356:T 330:1 326:T 313:. 301:) 296:m 292:a 288:, 282:, 277:1 273:a 269:( 235:m 231:a 227:, 221:, 216:1 212:a 184:T 162:1 158:T 137:T 111:) 106:m 102:x 98:, 92:, 87:1 83:x 79:( 70:m 66:x 54:1 50:x

Index

mathematical logic
theory
Extension by definitions
first-order theory
language
axiom
conservative extension
functional symbol
conservative extension
Conservative extension
Extension by definition
Shoenfield, Joseph
v
t
e
Mathematical logic
Axiom
list
Cardinality
First-order logic
Formal proof
Formal semantics
Foundations of mathematics
Information theory
Lemma
Logical consequence
Model
Theorem
Theory
Type theory

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