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4243: 1395: 373:. Theorems are often described as being "trivial", or "difficult", or "deep", or even "beautiful". These subjective judgments vary not only from person to person, but also with time and culture: for example, as a proof is obtained, simplified or better understood, a theorem that was once difficult may become trivial. On the other hand, a deep theorem may be stated simply, but its proof may involve surprising and subtle connections between disparate areas of mathematics. 523:", in the sense that they follow from definitions, axioms, and other theorems in obvious ways and do not contain any surprising insights. Some, on the other hand, may be called "deep", because their proofs may be long and difficult, involve areas of mathematics superficially distinct from the statement of the theorem itself, or show surprising connections between disparate areas of mathematics. A theorem might be simple to state and yet be deep. An excellent example is 504: 46: 1145: 567:. Any disagreement between prediction and experiment demonstrates the incorrectness of the scientific theory, or at least limits its accuracy or domain of validity. Mathematical theorems, on the other hand, are purely abstract formal statements: the proof of a theorem cannot involve experiments or other empirical evidence in the same way such evidence is used to support scientific theories. 358:), they are often expressed informally in a natural language such as English for better readability. The same is true of proofs, which are often expressed as logically organized and clearly worded informal arguments, intended to convince readers of the truth of the statement of the theorem beyond any doubt, and from which a formal symbolic proof can in principle be constructed. 571: 2328: 2434: 1381: 1214:
Although theorems may be uninterpreted sentences, in practice mathematicians are more interested in the meanings of the sentences, i.e. in the propositions they express. What makes formal theorems useful and interesting is that they may be interpreted as true propositions and their derivations may be
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Nonetheless, there is some degree of empiricism and data collection involved in the discovery of mathematical theorems. By establishing a pattern, sometimes with the use of a powerful computer, mathematicians may have an idea of what to prove, and in some cases even a plan for how to set about doing
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In this context, the validity of a theorem depends only on the correctness of its proof. It is independent from the truth, or even the significance of the axioms. This does not mean that the significance of the axioms is uninteresting, but only that the validity of a theorem is independent from the
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is regarded by some to be the longest proof of a theorem. It comprises tens of thousands of pages in 500 journal articles by some 100 authors. These papers are together believed to give a complete proof, and several ongoing projects hope to shorten and simplify this proof. Another theorem of this
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that specifies how the theorems are derived. The deductive system may be stated explicitly, or it may be clear from the context. The closure of the empty set under the relation of logical consequence yields the set that contains just those sentences that are the theorems of the deductive system.
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describing the exact meaning of the terms used in the theorem. It is also common for a theorem to be preceded by a number of propositions or lemmas which are then used in the proof. However, lemmas are sometimes embedded in the proof of a theorem, either with nested proofs, or with their proofs
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has even gone so far as to claim that these are possibly the only nontrivial results that mathematicians have ever proved. Many mathematical theorems can be reduced to more straightforward computation, including polynomial identities, trigonometric identities and hypergeometric identities.
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In order for a theorem to be proved, it must be in principle expressible as a precise, formal statement. However, theorems are usually expressed in natural language rather than in a completely symbolic form—with the presumption that a formal statement can be derived from the informal one.
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In addition to the better readability, informal arguments are typically easier to check than purely symbolic ones—indeed, many mathematicians would express a preference for a proof that not only demonstrates the validity of a theorem, but also explains in some way
230:. All theorems were proved by using implicitly or explicitly these basic properties, and, because of the evidence of these basic properties, a proved theorem was considered as a definitive truth, unless there was an error in the proof. For example, the sum of the 542:. Both of these theorems are only known to be true by reducing them to a computational search that is then verified by a computer program. Initially, many mathematicians did not accept this form of proof, but it has become more widely accepted. The mathematician 672:
A number of different terms for mathematical statements exist; these terms indicate the role statements play in a particular subject. The distinction between different terms is sometimes rather arbitrary, and the usage of some terms has evolved over time.
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It is common in mathematics to choose a number of hypotheses within a given language and declare that the theory consists of all statements provable from these hypotheses. These hypotheses form the foundational basis of the theory and are called
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the proof. It is also possible to find a single counter-example and so establish the impossibility of a proof for the proposition as-stated, and possibly suggest restricted forms of the original proposition that might have feasible proofs.
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In general, the distinction is weak, as the standard way to prove that a statement is provable consists of proving it. However, in mathematical logic, one considers often the set of all theorems of a theory, although one cannot prove them
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Often, when the less general or "corollary"-like theorem is proven first, it is because the proof of the more general form requires the simpler, corollary-like form, for use as a what is functionally a lemma, or "helper"
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Corollaries to a theorem are either presented between the theorem and the proof, or directly after the proof. Sometimes, corollaries have proofs of their own that explain why they follow from the theorem.
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with no free variables. A sentence that is a member of a theory is one of its theorems, and the theory is the set of its theorems. Usually a theory is understood to be closed under the relation of
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is a theorem of lesser importance, or one that is considered so elementary or immediately obvious, that it may be stated without proof. This should not be confused with "proposition" as used in
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of the hypotheses. Namely, that the conclusion is true in case the hypotheses are true—without any further assumptions. However, the conditional could also be interpreted differently in certain
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is a proposition that follows immediately from another theorem or axiom, with little or no required proof. A corollary may also be a restatement of a theorem in a simpler form, or for a
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of 1.59 Ă— 10, which is approximately 10 to the power 4.3 Ă— 10. Since the number of particles in the universe is generally considered less than 10 to the power 100 (a
1918: 1172:. A formal language can be thought of as identical to the set of its well-formed formulas. The set of well-formed formulas may be broadly divided into theorems and non-theorems. 112:. Generally, an assertion that is explicitly called a theorem is a proved result that is not an immediate consequence of other known theorems. Moreover, many authors qualify as 2622: 311:. In particular, there are well-formed assertions than can be proved to not be a theorem of the ambient theory, although they can be proved in a wider theory. An example is 159:(sometimes included in the axioms). The theorems of the theory are the statements that can be derived from the axioms by using the deducing rules. This formalization led to 780:
is an "accessory proposition" - a proposition with little applicability outside its use in a particular proof. Over time a lemma may gain in importance and be considered a
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whose computer generated proof is too long for a human to read. It is among the longest known proofs of a theorem whose statement can be easily understood by a layman.
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cannot be expressed with a well-formed formula. More precisely, if the set of all sets can be expressed with a well-formed formula, this implies that the theory is
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theory containing the natural numbers has true statements on natural numbers that are not theorems of the theory (that is they cannot be proved inside the theory).
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significance of the axioms. This independence may be useful by allowing the use of results of some area of mathematics in apparently unrelated areas.
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states that such colorings are possible for any planar map, but every known proof involves a computational search that is too long to check by hand.
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that do not lead to any contradiction, although, in such geometries, the sum of the angles of a triangle is different from 180°. So, the property
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is either true or false, depending whether Euclid's fifth postulate is assumed or denied. Similarly, the use of "evident" basic properties of
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In mainstream mathematics, the axioms and the inference rules are commonly left implicit, and, in this case, they are almost always those of
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map with five colors such that no two regions with the same color meet. It can actually be colored in this way with only four colors. The
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In the broad sense in which the term is used within logic, a theorem does not have to be true, since the theory that contains it may be
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is an unproved statement that is believed to be true. Conjectures are usually made in public, and named after their maker (for example,
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The word "theory" also exists in mathematics, to denote a body of mathematical axioms, definitions and theorems, as in, for example,
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Other theorems have a known proof that cannot easily be written down. The most prominent examples are the four color theorem and the
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An important consequence of this way of thinking about mathematics is that it allows defining mathematical theories and theorems as
578:: one way to illustrate its complexity is to extend the iteration from the natural numbers to the complex numbers. The result is a 909: 3945: 3689: 2514: 1921: 583: 3250: 2943: 2684: 1271: 726:), which should not be confused with "hypothesis" as the premise of a proof. Other terms are also used on occasion, for example 320: 101: 1557: 4206: 3908: 3671: 3666: 3491: 2912: 2596: 2186: 218:
that passes through two given distinct points. These basic properties that were considered as absolutely evident were called
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of a theorem is a theorem with a similar statement but a broader scope, from which the original theorem can be deduced as a
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A theory is often identified with the set of its theorems. This is avoided here for clarity, and also for not depending on
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is a statement about natural numbers that is now known to be false, but no explicit counterexample (i.e., a natural number
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is a fundamental assumption regarding the object of study, that is accepted without proof. A related concept is that of a
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McLarty, Colin (2010). "What does it take to prove Fermat's last theorem? Grothendieck and the logic of number theory".
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are well-known unsolved problems; they have been extensively studied through empirical checks, but remain unproven. The
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it is obviously true. In some cases, one might even be able to substantiate a theorem by using a picture as its proof.
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Many mathematical theorems are conditional statements, whose proofs deduce conclusions from conditions known as
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McLarty, Colin (2020). "The large structures of Grothendieck founded on finite order arithmetic".
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Originally published in 1940 and reprinted in 1968 by National Council of Teachers of Mathematics.
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The exact style depends on the author or publication. Many publications provide instructions or
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is a theorem stating an equality between two expressions, that holds for any value within its
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This crisis has been resolved by revisiting the foundations of mathematics to make them more
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The concept of a formal theorem is fundamentally syntactic, in contrast to the notion of a
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interpreted as a proof of their truth. A theorem whose interpretation is a true statement
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Although theorems can be written in a completely symbolic form (e.g., as propositions in
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in order to allow mathematical reasoning about them. In this context, statements become
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It has been estimated that over a quarter of a million theorems are proved every year.
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For a theory to be closed under a derivability relation, it must be associated with a
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was historically called a theorem, although, for centuries, it was only a conjecture.
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Theorems in mathematics and theories in science are fundamentally different in their
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of the theory. So, the above theorem on the sum of the angles of a triangle becomes:
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has been verified to hold for the first 10 trillion non-trivial zeroes of the
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is a statement that has been proven to be true based on axioms and other theorems.
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However, both theorems and scientific law are the result of investigations. See
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A few well-known theorems have even more idiosyncratic names, for example, the
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Other terms may also be used for historical or customary reasons, for example:
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is a tentative proposition that may evolve to become a theorem if proven true.
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The definition of theorems as sentences of a formal language is useful within
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when people are not sure whether the statement should be believed to be true.
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Because theorems lie at the core of mathematics, they are also central to its
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Metalogic: An Introduction to the Metatheory of Standard First Order Logic
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of a formal system depends on whether or not all of its theorems are also
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One aspect of the foundational crisis of mathematics was the discovery of
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has been verified for start values up to about 2.88 Ă— 10. The
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of the theorem ("hypothesis" here means something very different from a
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of the theorem. The two together (without the proof) are called the
2365: 1726:(Fall 2017 ed.), Metaphysics Research Lab, Stanford University 527:, and there are many other examples of simple yet deep theorems in 3353: 2699: 2544: 2357: 1684: 1143: 679: 569: 502: 493: 273: 223: 94: 44: 995:
marks, such as "□" or "∎", meaning "end of proof", introduced by
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following their use in magazines to mark the end of an article.
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An enormous theorem: the classification of finite simple groups
1039:"A mathematician is a device for turning coffee into theorems" 500:
studies formal languages, axioms and the structure of proofs.
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equals 180°, and this was considered as an undoubtable fact.
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McGill University – Department of Mathematics and Statistics
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Darmon, Henri; Diamond, Fred; Taylor, Richard (2007-09-09).
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Petkovsek, Marko; Wilf, Herbert; Zeilberger, Doron (1996).
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relative to a given semantics, or relative to the standard
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A theorem and its proof are typically laid out as follows:
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Such evidence does not constitute proof. For example, the
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As the axioms are often abstractions of properties of the
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Gödel's incompleteness theorems of first-order arithmetic
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Boolos, George; Burgess, John; Jeffrey, Richard (2007).
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is a particularly well-known example of such a theorem.
188:, the justification of the truth of a theorem is purely 2014:, Richard Elwes, Plus Magazine, Issue 41 December 2006. 1093:. Some accounts define a theory to be closed under the 1045:, although it is often attributed to RĂ©nyi's colleague 1888: 1127: 1103: 877:
is a theorem that establishes a useful formula (e.g.
809:: for example, the theorem "all internal angles in a 983:
The end of the proof may be signaled by the letters
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involves the existence of very large infinite sets.
1232:Some important theorems in mathematical logic are: 480:
is an even natural number", and the conclusion is "
116:only the most important results, and use the terms 2250: 1970:"Earliest Uses of Symbols of Set Theory and Logic" 1912: 1133: 1109: 1117:), while others define it to be closed under the 827:" - a square being a special case of a rectangle. 817:" has a corollary that "all internal angles in a 496:or postulates. The field of mathematics known as 307:, and to prove theorems about them. Examples are 247:"the sum of the angles of a triangle equals 180°" 1053:of his collaborations, and his coffee drinking. 214:has a successor, and that there is exactly one 135:, the concepts of theorems and proofs have been 27:In mathematics, a statement that has been proven 1343:when all of its theorems are also tautologies. 900:is a theorem with wide applicability (e.g. the 2515: 2381: 1192:of the underlying language. A theory that is 1013:It is common for a theorem to be preceded by 108:(ZFC), or of a less powerful theory, such as 8: 2304:A Concise Introduction to Mathematical Logic 2122:(5th ed.). Cambridge University Press. 1607:"Theorem | Definition of Theorem by Lexico" 959:Statement of theorem (sometimes called the 264:. In these new foundations, a theorem is a 3341: 2936: 2704: 2522: 2508: 2500: 2388: 2374: 2366: 1882:Such as the derivation of the formula for 1678:(2). Cambridge University Press: 296–325. 1643:(3). Cambridge University Press: 359–377. 1018:presented after the proof of the theorem. 722:is also used in this sense (for example, 206:Until the end of the 19th century and the 2287:. A.K. Peters, Wellesley, Massachusetts. 1887: 1683: 1126: 1102: 151:consists of some basis statements called 2140:(2nd ed.). Harcourt Academic Press. 282:Under the axioms and inference rules of 2127:Chiswell, Ian; Hodges, Wilfred (2007). 1724:The Stanford Encyclopedia of Philosophy 1535: 1445: 1262:Church-Turing theorem of undecidability 637:) equals or exceeds the square root of 1949:. Ginn & Co. Articles 46, 47. 1553:Education Resources Information Center 1464:Wiles's proof of Fermat's Last Theorem 1058:classification of finite simple groups 388:, many theorems are of the form of an 1783: 1781: 1743: 1252:Consistency of first-order arithmetic 7: 2138:A Mathematical Introduction to Logic 1922:addition formulas of sine and cosine 1913:{\displaystyle \tan(\alpha +\beta )} 1713: 1711: 1943:Wentworth, G.; Smith, D.E. (1913). 1419:List of theorems called fundamental 89:to establish that the theorem is a 85:that uses the inference rules of a 2222:. University of California Press. 2177:Fundamentals of Mathematical Logic 1347:Interpretation of a formal theorem 208:foundational crisis of mathematics 25: 1959:Wentworth & Smith, article 51 1746:Introduction, The terminology of 1339:). A formal system is considered 1242:Completeness of first-order logic 551:Relation with scientific theories 396:. Such a theorem does not assert 4241: 2432: 2326: 2315:(3rd ed.). Springer-Verlag. 1393: 1379: 1237:Compactness of first-order logic 464:, respectively. The theorem "If 97:and previously proved theorems. 1558:Institute of Education Sciences 1257:Tarski's undefinability theorem 1219:a formal system (as opposed to 1196:has all sentences as theorems. 1081:is a set of sentences within a 629:for which the Mertens function 309:Gödel's incompleteness theorems 165:Gödel's incompleteness theorems 2187:The Man Who Loved Only Numbers 1907: 1895: 1510:can also refer to an axiom, a 484:/2 is also a natural number". 404:is a necessary consequence of 327:Epistemological considerations 253:leads to the contradiction of 53:has at least 370 known proofs. 1: 4202:History of mathematical logic 2302:Rautenberg, Wolfgang (2010). 2241:. Cambridge University Press. 2239:Notes on Logic and Set Theory 2210:. Cambridge University Press. 1722:, in Zalta, Edward N. (ed.), 1611:Lexico Dictionaries | English 1466:, which relies implicitly on 1462:An exception is the original 1223:a formal system) is called a 1152:that can be constructed from 765: 128:for less important theorems. 4127:Primitive recursive function 2179:. Wellesley, MA: A K Peters. 2032:Chiswell and Hodges, p. 172. 1720:"Rationalism vs. Empiricism" 1637:The Review of Symbolic Logic 1562:U.S. Department of Education 1164:may be broadly divided into 1121:, or derivability relation ( 582:, which (in accordance with 381:Informal account of theorems 272:that can be proved from the 2257:. Oxford University Press. 2023:Boolos, et al 2007, p. 191. 1368:Theory (mathematical logic) 918:least-upper-bound principle 321:Zermelo–Fraenkel set theory 102:Zermelo–Fraenkel set theory 4314: 3191:Schröder–Bernstein theorem 2918:Monadic predicate calculus 2577:Foundations of mathematics 2170:. Oxford University Press. 2136:Enderton, Herbert (2001). 2131:. Oxford University Press. 1672:Bulletin of Symbolic Logic 1361: 1350: 1296: 29: 4237: 4224:Philosophy of mathematics 4173:Automated theorem proving 3344: 3298:Von Neumann–Bernays–Gödel 2939: 2430: 2306:(3rd ed.). Springer. 2237:Johnstone, P. T. (1987). 1694:10.1017/S1755020319000340 910:Kolmogorov's zero–one law 697:"; today they are merely 315:, which can be stated in 4288:Mathematical terminology 2311:van Dalen, Dirk (1994). 2272:Monk, J. Donald (1976). 2206:Hodges, Wilfrid (1993). 2146:Heath, Sir Thomas Little 1520:probability distribution 1303:Formal semantics (logic) 1272:Löwenheim–Skolem theorem 1110:{\displaystyle \models } 243:non-Euclidean geometries 77:, or can be proven. The 30:Not to be confused with 3874:Self-verifying theories 3695:Tarski's axiomatization 2646:Tarski's undefinability 2641:incompleteness theorems 2168:A First Course in Logic 2151:The works of Archimedes 2120:Computability and Logic 1821:intrologic.stanford.edu 1790:"Fermat's Last Theorem" 1583:"Definition of THEOREM" 1287:Cut-elimination theorem 1148:This diagram shows the 1134:{\displaystyle \vdash } 1006:for typesetting in the 989:quod erat demonstrandum 452:can be also termed the 4248:Mathematics portal 3859:Proof of impossibility 3507:propositional variable 2817:Propositional calculus 2191:. Hyperion, New York. 2175:Hinman, Peter (2005). 2166:Hedman, Shawn (2004). 1993:Hoffman 1998, p. 204. 1933:Petkovsek et al. 1996. 1914: 1718:Markie, Peter (2017), 1649:10.2178/bsl/1286284558 1468:Grothendieck universes 1353:Interpretation (logic) 1173: 1135: 1111: 868:Vandermonde's identity 598:For example, both the 591: 516: 436:of the theorem (e.g. " 390:indicative conditional 356:propositional calculus 54: 4117:Kolmogorov complexity 4070:Computably enumerable 3970:Model complete theory 3762:Principia Mathematica 2822:Propositional formula 2651:Banach–Tarski paradox 1915: 1766:mathworld.wolfram.com 1543:Elisha Scott Loomis. 1358:Theorems and theories 1341:semantically complete 1147: 1136: 1119:syntactic consequence 1112: 1041:, is probably due to 938:Banach–Tarski paradox 794:the fundamental lemma 732:Fermat's Last Theorem 712:Goldbach's conjecture 573: 535:, among other areas. 525:Fermat's Last Theorem 506: 375:Fermat's Last Theorem 341:necessary consequence 202:Theoremhood and truth 48: 4065:Church–Turing thesis 4052:Computability theory 3261:continuum hypothesis 2779:Square of opposition 2637:Gödel's completeness 2335:at Wikimedia Commons 2184:Hoffman, P. (1998). 1886: 1293:Syntax and semantics 1170:well-formed formulas 1125: 1101: 1095:semantic consequence 973:Description of proof 922:pigeonhole principle 902:law of large numbers 305:mathematical objects 141:well-formed formulas 4283:Mathematical proofs 4278:Logical expressions 4273:Logical consequence 4219:Mathematical object 4110:P versus NP problem 4075:Computable function 3869:Reverse mathematics 3795:Logical consequence 3672:primitive recursive 3667:elementary function 3440:Free/bound variable 3293:Tarski–Grothendieck 2812:Logical connectives 2742:Logical equivalence 2592:Logical consequence 2313:Logic and Structure 2002:Hoffman 1998, p. 7. 1760:Weisstein, Eric W. 1617:on November 2, 2019 1277:Lindström's theorem 1091:logical consequence 1087:well-formed formula 991:) or by one of the 914:Harnack's principle 769: 300 BCE 752:propositional logic 662:mathematical theory 519:Some theorems are " 349:non-classical logic 313:Goodstein's theorem 270:mathematical theory 266:well-formed formula 228:Euclid's postulates 91:logical consequence 51:Pythagorean theorem 4017:Transfer principle 3980:Semantics of logic 3965:Categorical theory 3941:Non-standard model 3455:Logical connective 2582:Information theory 2531:Mathematical logic 2358:Theorem of the Day 2341:Weisstein, Eric W. 2276:. Springer-Verlag. 2274:Mathematical Logic 2129:Mathematical Logic 2104:van Dalen, p. 104. 2095:Rautenberg, p. 81. 1974:jeff560.tripod.com 1910: 1842:Weisstein, Eric W. 1516:probability theory 1401:Mathematics portal 1174: 1162:strings of symbols 1150:syntactic entities 1131: 1107: 1085:. A sentence is a 1075:mathematical logic 1063:four color theorem 930:division algorithm 724:Riemann hypothesis 716:Collatz conjecture 623:Mertens conjecture 612:Riemann hypothesis 608:Collatz conjecture 604:Riemann hypothesis 600:Collatz conjecture 592: 576:Collatz conjecture 517: 513:four color theorem 444:). Alternatively, 284:Euclidean geometry 133:mathematical logic 81:of a theorem is a 55: 4298:Concepts in logic 4255: 4254: 4187:Abstract category 3990:Theories of truth 3800:Rule of inference 3790:Natural deduction 3771: 3770: 3316: 3315: 3021:Cartesian product 2926: 2925: 2832:Many-valued logic 2807:Boolean functions 2690:Russell's paradox 2665:diagonal argument 2562:First-order logic 2497: 2496: 2331:Media related to 2077:Johnstone, p. 21. 1512:rule of inference 1409:Law (mathematics) 1387:Philosophy portal 1311:which introduces 1309:true proposition, 1069:Theorems in logic 864:BĂ©zout's identity 651:exhaustive search 540:Kepler conjecture 345:deductive systems 255:Russell's paradox 16:(Redirected from 4305: 4246: 4245: 4197:History of logic 4192:Category of sets 4085:Decision problem 3864:Ordinal analysis 3805:Sequent calculus 3703:Boolean algebras 3643: 3642: 3617: 3588:logical/constant 3342: 3328: 3251:Zermelo–Fraenkel 3002:Set operations: 2937: 2874: 2705: 2685:Löwenheim–Skolem 2572:Formal semantics 2524: 2517: 2510: 2501: 2436: 2390: 2383: 2376: 2367: 2354: 2353: 2330: 2316: 2307: 2298: 2277: 2268: 2256: 2253:Elementary Logic 2242: 2233: 2216:Hunter, Geoffrey 2211: 2202: 2180: 2171: 2162: 2160: 2159: 2141: 2132: 2123: 2105: 2102: 2096: 2093: 2087: 2084: 2078: 2075: 2069: 2066: 2060: 2057: 2051: 2048: 2042: 2041:Enderton, p. 148 2039: 2033: 2030: 2024: 2021: 2015: 2009: 2003: 2000: 1994: 1991: 1985: 1984: 1982: 1980: 1966: 1960: 1957: 1951: 1950: 1940: 1934: 1931: 1925: 1919: 1917: 1916: 1911: 1880: 1874: 1873: 1866:Doron Zeilberger 1862: 1856: 1855: 1854: 1837: 1831: 1830: 1828: 1827: 1813: 1807: 1806: 1804: 1803: 1794: 1785: 1776: 1775: 1773: 1772: 1757: 1751: 1740: 1734: 1733: 1732: 1731: 1715: 1706: 1705: 1687: 1667: 1661: 1660: 1632: 1626: 1625: 1623: 1622: 1613:. Archived from 1603: 1597: 1596: 1594: 1593: 1579: 1573: 1571: 1569: 1568: 1549: 1540: 1523: 1504: 1498: 1494: 1488: 1481: 1475: 1460: 1454: 1450: 1414:List of theorems 1403: 1398: 1397: 1389: 1384: 1383: 1382: 1178:deductive system 1154:formal languages 1140: 1138: 1137: 1132: 1116: 1114: 1113: 1108: 770: 767: 586:) resembles the 544:Doron Zeilberger 408:. In this case, 317:Peano arithmetic 167:show that every 110:Peano arithmetic 87:deductive system 83:logical argument 21: 4313: 4312: 4308: 4307: 4306: 4304: 4303: 4302: 4258: 4257: 4256: 4251: 4240: 4233: 4178:Category theory 4168:Algebraic logic 4151: 4122:Lambda calculus 4060:Church encoding 4046: 4022:Truth predicate 3878: 3844:Complete theory 3767: 3636: 3632: 3628: 3623: 3615: 3335: and  3331: 3326: 3312: 3288:New Foundations 3256:axiom of choice 3239: 3201:Gödel numbering 3141: and  3133: 3037: 2922: 2872: 2853: 2802:Boolean algebra 2788: 2752:Equiconsistency 2717:Classical logic 2694: 2675:Halting problem 2663: and  2639: and  2627: and  2626: 2621:Theorems ( 2616: 2533: 2528: 2498: 2493: 2463: 2437: 2428: 2401: 2394: 2363: 2339: 2338: 2323: 2310: 2301: 2295: 2280: 2271: 2265: 2245: 2236: 2230: 2214: 2205: 2199: 2183: 2174: 2165: 2157: 2155: 2144: 2135: 2126: 2117: 2114: 2109: 2108: 2103: 2099: 2094: 2090: 2085: 2081: 2076: 2072: 2067: 2063: 2059:Hinman, p. 139. 2058: 2054: 2049: 2045: 2040: 2036: 2031: 2027: 2022: 2018: 2010: 2006: 2001: 1997: 1992: 1988: 1978: 1976: 1968: 1967: 1963: 1958: 1954: 1942: 1941: 1937: 1932: 1928: 1884: 1883: 1881: 1877: 1864: 1863: 1859: 1840: 1839: 1838: 1834: 1825: 1823: 1815: 1814: 1810: 1801: 1799: 1792: 1787: 1786: 1779: 1770: 1768: 1759: 1758: 1754: 1741: 1737: 1729: 1727: 1717: 1716: 1709: 1669: 1668: 1664: 1634: 1633: 1629: 1620: 1618: 1605: 1604: 1600: 1591: 1589: 1587:Merriam-Webster 1581: 1580: 1576: 1566: 1564: 1547: 1542: 1541: 1537: 1532: 1527: 1526: 1505: 1501: 1495: 1491: 1482: 1478: 1461: 1457: 1451: 1447: 1442: 1399: 1392: 1385: 1380: 1378: 1375: 1370: 1362:Main articles: 1360: 1355: 1349: 1305: 1297:Main articles: 1295: 1282:Craig's theorem 1123: 1122: 1099: 1098: 1083:formal language 1071: 1033:The well-known 1028: 946: 934:Euler's formula 768: 670: 553: 383: 329: 290:set of all sets 278:inference rules 232:interior angles 204: 145:formal language 106:axiom of choice 43: 28: 23: 22: 15: 12: 11: 5: 4311: 4309: 4301: 4300: 4295: 4290: 4285: 4280: 4275: 4270: 4260: 4259: 4253: 4252: 4238: 4235: 4234: 4232: 4231: 4226: 4221: 4216: 4211: 4210: 4209: 4199: 4194: 4189: 4180: 4175: 4170: 4165: 4163:Abstract logic 4159: 4157: 4153: 4152: 4150: 4149: 4144: 4142:Turing machine 4139: 4134: 4129: 4124: 4119: 4114: 4113: 4112: 4107: 4102: 4097: 4092: 4082: 4080:Computable set 4077: 4072: 4067: 4062: 4056: 4054: 4048: 4047: 4045: 4044: 4039: 4034: 4029: 4024: 4019: 4014: 4009: 4008: 4007: 4002: 3997: 3987: 3982: 3977: 3975:Satisfiability 3972: 3967: 3962: 3961: 3960: 3950: 3949: 3948: 3938: 3937: 3936: 3931: 3926: 3921: 3916: 3906: 3905: 3904: 3899: 3892:Interpretation 3888: 3886: 3880: 3879: 3877: 3876: 3871: 3866: 3861: 3856: 3846: 3841: 3840: 3839: 3838: 3837: 3827: 3822: 3812: 3807: 3802: 3797: 3792: 3787: 3781: 3779: 3773: 3772: 3769: 3768: 3766: 3765: 3757: 3756: 3755: 3754: 3749: 3748: 3747: 3742: 3737: 3717: 3716: 3715: 3713:minimal axioms 3710: 3699: 3698: 3697: 3686: 3685: 3684: 3679: 3674: 3669: 3664: 3659: 3646: 3644: 3625: 3624: 3622: 3621: 3620: 3619: 3607: 3602: 3601: 3600: 3595: 3590: 3585: 3575: 3570: 3565: 3560: 3559: 3558: 3553: 3543: 3542: 3541: 3536: 3531: 3526: 3516: 3511: 3510: 3509: 3504: 3499: 3489: 3488: 3487: 3482: 3477: 3472: 3467: 3462: 3452: 3447: 3442: 3437: 3436: 3435: 3430: 3425: 3420: 3410: 3405: 3403:Formation rule 3400: 3395: 3394: 3393: 3388: 3378: 3377: 3376: 3366: 3361: 3356: 3351: 3345: 3339: 3322:Formal systems 3318: 3317: 3314: 3313: 3311: 3310: 3305: 3300: 3295: 3290: 3285: 3280: 3275: 3270: 3265: 3264: 3263: 3258: 3247: 3245: 3241: 3240: 3238: 3237: 3236: 3235: 3225: 3220: 3219: 3218: 3211:Large cardinal 3208: 3203: 3198: 3193: 3188: 3174: 3173: 3172: 3167: 3162: 3147: 3145: 3135: 3134: 3132: 3131: 3130: 3129: 3124: 3119: 3109: 3104: 3099: 3094: 3089: 3084: 3079: 3074: 3069: 3064: 3059: 3054: 3048: 3046: 3039: 3038: 3036: 3035: 3034: 3033: 3028: 3023: 3018: 3013: 3008: 3000: 2999: 2998: 2993: 2983: 2978: 2976:Extensionality 2973: 2971:Ordinal number 2968: 2958: 2953: 2952: 2951: 2940: 2934: 2928: 2927: 2924: 2923: 2921: 2920: 2915: 2910: 2905: 2900: 2895: 2890: 2889: 2888: 2878: 2877: 2876: 2863: 2861: 2855: 2854: 2852: 2851: 2850: 2849: 2844: 2839: 2829: 2824: 2819: 2814: 2809: 2804: 2798: 2796: 2790: 2789: 2787: 2786: 2781: 2776: 2771: 2766: 2761: 2756: 2755: 2754: 2744: 2739: 2734: 2729: 2724: 2719: 2713: 2711: 2702: 2696: 2695: 2693: 2692: 2687: 2682: 2677: 2672: 2667: 2655:Cantor's  2653: 2648: 2643: 2633: 2631: 2618: 2617: 2615: 2614: 2609: 2604: 2599: 2594: 2589: 2584: 2579: 2574: 2569: 2564: 2559: 2554: 2553: 2552: 2541: 2539: 2535: 2534: 2529: 2527: 2526: 2519: 2512: 2504: 2495: 2494: 2492: 2491: 2486: 2481: 2471: 2469: 2468:Negation  2465: 2464: 2462: 2461: 2456: 2451: 2445: 2443: 2439: 2438: 2431: 2429: 2427: 2426: 2420: 2418:truth function 2415: 2409: 2407: 2403: 2402: 2395: 2393: 2392: 2385: 2378: 2370: 2361: 2360: 2355: 2336: 2322: 2321:External links 2319: 2318: 2317: 2308: 2299: 2293: 2278: 2269: 2263: 2243: 2234: 2228: 2212: 2203: 2197: 2181: 2172: 2163: 2142: 2133: 2124: 2113: 2110: 2107: 2106: 2097: 2088: 2079: 2070: 2068:Hodges, p. 33. 2061: 2052: 2050:Hedman, p. 89. 2043: 2034: 2025: 2016: 2004: 1995: 1986: 1961: 1952: 1946:Plane Geometry 1935: 1926: 1909: 1906: 1903: 1900: 1897: 1894: 1891: 1875: 1857: 1845:"Deep Theorem" 1832: 1808: 1777: 1752: 1735: 1707: 1662: 1627: 1598: 1574: 1534: 1533: 1531: 1528: 1525: 1524: 1499: 1489: 1476: 1455: 1444: 1443: 1441: 1438: 1437: 1436: 1431: 1426: 1421: 1416: 1411: 1405: 1404: 1390: 1374: 1371: 1359: 1356: 1351:Main article: 1348: 1345: 1299:Syntax (logic) 1294: 1291: 1290: 1289: 1284: 1279: 1274: 1269: 1264: 1259: 1254: 1249: 1244: 1239: 1209:interpretation 1190:interpretation 1130: 1106: 1070: 1067: 1027: 1024: 981: 980: 975: 970: 965: 956: 945: 942: 926: 925: 906:law of cosines 886: 871: 846: 845: 833:generalization 828: 797: 772: 742: 735: 702: 669: 666: 588:Mandelbrot set 552: 549: 470:natural number 412:is called the 382: 379: 328: 325: 226:; for example 212:natural number 203: 200: 180:scientific law 176:physical world 157:deducing rules 73:that has been 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 4310: 4299: 4296: 4294: 4291: 4289: 4286: 4284: 4281: 4279: 4276: 4274: 4271: 4269: 4266: 4265: 4263: 4250: 4249: 4244: 4236: 4230: 4227: 4225: 4222: 4220: 4217: 4215: 4212: 4208: 4205: 4204: 4203: 4200: 4198: 4195: 4193: 4190: 4188: 4184: 4181: 4179: 4176: 4174: 4171: 4169: 4166: 4164: 4161: 4160: 4158: 4154: 4148: 4145: 4143: 4140: 4138: 4137:Recursive set 4135: 4133: 4130: 4128: 4125: 4123: 4120: 4118: 4115: 4111: 4108: 4106: 4103: 4101: 4098: 4096: 4093: 4091: 4088: 4087: 4086: 4083: 4081: 4078: 4076: 4073: 4071: 4068: 4066: 4063: 4061: 4058: 4057: 4055: 4053: 4049: 4043: 4040: 4038: 4035: 4033: 4030: 4028: 4025: 4023: 4020: 4018: 4015: 4013: 4010: 4006: 4003: 4001: 3998: 3996: 3993: 3992: 3991: 3988: 3986: 3983: 3981: 3978: 3976: 3973: 3971: 3968: 3966: 3963: 3959: 3956: 3955: 3954: 3951: 3947: 3946:of arithmetic 3944: 3943: 3942: 3939: 3935: 3932: 3930: 3927: 3925: 3922: 3920: 3917: 3915: 3912: 3911: 3910: 3907: 3903: 3900: 3898: 3895: 3894: 3893: 3890: 3889: 3887: 3885: 3881: 3875: 3872: 3870: 3867: 3865: 3862: 3860: 3857: 3854: 3853:from ZFC 3850: 3847: 3845: 3842: 3836: 3833: 3832: 3831: 3828: 3826: 3823: 3821: 3818: 3817: 3816: 3813: 3811: 3808: 3806: 3803: 3801: 3798: 3796: 3793: 3791: 3788: 3786: 3783: 3782: 3780: 3778: 3774: 3764: 3763: 3759: 3758: 3753: 3752:non-Euclidean 3750: 3746: 3743: 3741: 3738: 3736: 3735: 3731: 3730: 3728: 3725: 3724: 3722: 3718: 3714: 3711: 3709: 3706: 3705: 3704: 3700: 3696: 3693: 3692: 3691: 3687: 3683: 3680: 3678: 3675: 3673: 3670: 3668: 3665: 3663: 3660: 3658: 3655: 3654: 3652: 3648: 3647: 3645: 3640: 3634: 3629:Example  3626: 3618: 3613: 3612: 3611: 3608: 3606: 3603: 3599: 3596: 3594: 3591: 3589: 3586: 3584: 3581: 3580: 3579: 3576: 3574: 3571: 3569: 3566: 3564: 3561: 3557: 3554: 3552: 3549: 3548: 3547: 3544: 3540: 3537: 3535: 3532: 3530: 3527: 3525: 3522: 3521: 3520: 3517: 3515: 3512: 3508: 3505: 3503: 3500: 3498: 3495: 3494: 3493: 3490: 3486: 3483: 3481: 3478: 3476: 3473: 3471: 3468: 3466: 3463: 3461: 3458: 3457: 3456: 3453: 3451: 3448: 3446: 3443: 3441: 3438: 3434: 3431: 3429: 3426: 3424: 3421: 3419: 3416: 3415: 3414: 3411: 3409: 3406: 3404: 3401: 3399: 3396: 3392: 3389: 3387: 3386:by definition 3384: 3383: 3382: 3379: 3375: 3372: 3371: 3370: 3367: 3365: 3362: 3360: 3357: 3355: 3352: 3350: 3347: 3346: 3343: 3340: 3338: 3334: 3329: 3323: 3319: 3309: 3306: 3304: 3301: 3299: 3296: 3294: 3291: 3289: 3286: 3284: 3281: 3279: 3276: 3274: 3273:Kripke–Platek 3271: 3269: 3266: 3262: 3259: 3257: 3254: 3253: 3252: 3249: 3248: 3246: 3242: 3234: 3231: 3230: 3229: 3226: 3224: 3221: 3217: 3214: 3213: 3212: 3209: 3207: 3204: 3202: 3199: 3197: 3194: 3192: 3189: 3186: 3182: 3178: 3175: 3171: 3168: 3166: 3163: 3161: 3158: 3157: 3156: 3152: 3149: 3148: 3146: 3144: 3140: 3136: 3128: 3125: 3123: 3120: 3118: 3117:constructible 3115: 3114: 3113: 3110: 3108: 3105: 3103: 3100: 3098: 3095: 3093: 3090: 3088: 3085: 3083: 3080: 3078: 3075: 3073: 3070: 3068: 3065: 3063: 3060: 3058: 3055: 3053: 3050: 3049: 3047: 3045: 3040: 3032: 3029: 3027: 3024: 3022: 3019: 3017: 3014: 3012: 3009: 3007: 3004: 3003: 3001: 2997: 2994: 2992: 2989: 2988: 2987: 2984: 2982: 2979: 2977: 2974: 2972: 2969: 2967: 2963: 2959: 2957: 2954: 2950: 2947: 2946: 2945: 2942: 2941: 2938: 2935: 2933: 2929: 2919: 2916: 2914: 2911: 2909: 2906: 2904: 2901: 2899: 2896: 2894: 2891: 2887: 2884: 2883: 2882: 2879: 2875: 2870: 2869: 2868: 2865: 2864: 2862: 2860: 2856: 2848: 2845: 2843: 2840: 2838: 2835: 2834: 2833: 2830: 2828: 2825: 2823: 2820: 2818: 2815: 2813: 2810: 2808: 2805: 2803: 2800: 2799: 2797: 2795: 2794:Propositional 2791: 2785: 2782: 2780: 2777: 2775: 2772: 2770: 2767: 2765: 2762: 2760: 2757: 2753: 2750: 2749: 2748: 2745: 2743: 2740: 2738: 2735: 2733: 2730: 2728: 2725: 2723: 2722:Logical truth 2720: 2718: 2715: 2714: 2712: 2710: 2706: 2703: 2701: 2697: 2691: 2688: 2686: 2683: 2681: 2678: 2676: 2673: 2671: 2668: 2666: 2662: 2658: 2654: 2652: 2649: 2647: 2644: 2642: 2638: 2635: 2634: 2632: 2630: 2624: 2619: 2613: 2610: 2608: 2605: 2603: 2600: 2598: 2595: 2593: 2590: 2588: 2585: 2583: 2580: 2578: 2575: 2573: 2570: 2568: 2565: 2563: 2560: 2558: 2555: 2551: 2548: 2547: 2546: 2543: 2542: 2540: 2536: 2532: 2525: 2520: 2518: 2513: 2511: 2506: 2505: 2502: 2490: 2489:inconsistency 2487: 2485: 2484:contradiction 2482: 2480: 2476: 2473: 2472: 2470: 2466: 2460: 2457: 2455: 2452: 2450: 2447: 2446: 2444: 2440: 2435: 2425: 2422:⊨  2421: 2419: 2416: 2414: 2411: 2410: 2408: 2404: 2399: 2398:Logical truth 2391: 2386: 2384: 2379: 2377: 2372: 2371: 2368: 2364: 2359: 2356: 2351: 2350: 2345: 2342: 2337: 2334: 2329: 2325: 2324: 2320: 2314: 2309: 2305: 2300: 2296: 2294:1-56881-063-6 2290: 2286: 2285: 2279: 2275: 2270: 2266: 2264:0-19-501491-X 2260: 2255: 2254: 2248: 2247:Mates, Benson 2244: 2240: 2235: 2231: 2229:0-520-02356-0 2225: 2221: 2217: 2213: 2209: 2204: 2200: 2198:1-85702-829-5 2194: 2190: 2188: 2182: 2178: 2173: 2169: 2164: 2153: 2152: 2147: 2143: 2139: 2134: 2130: 2125: 2121: 2116: 2115: 2111: 2101: 2098: 2092: 2089: 2086:Monk, p. 208. 2083: 2080: 2074: 2071: 2065: 2062: 2056: 2053: 2047: 2044: 2038: 2035: 2029: 2026: 2020: 2017: 2013: 2008: 2005: 1999: 1996: 1990: 1987: 1975: 1971: 1965: 1962: 1956: 1953: 1948: 1947: 1939: 1936: 1930: 1927: 1923: 1904: 1901: 1898: 1892: 1889: 1879: 1876: 1871: 1867: 1861: 1858: 1852: 1851: 1846: 1843: 1836: 1833: 1822: 1818: 1817:"Implication" 1812: 1809: 1798: 1791: 1784: 1782: 1778: 1767: 1763: 1756: 1753: 1749: 1745: 1739: 1736: 1725: 1721: 1714: 1712: 1708: 1703: 1699: 1695: 1691: 1686: 1681: 1677: 1673: 1666: 1663: 1658: 1654: 1650: 1646: 1642: 1638: 1631: 1628: 1616: 1612: 1608: 1602: 1599: 1588: 1584: 1578: 1575: 1563: 1560:(IES) of the 1559: 1555: 1554: 1546: 1539: 1536: 1529: 1521: 1517: 1513: 1509: 1503: 1500: 1493: 1490: 1486: 1480: 1477: 1473: 1469: 1465: 1459: 1456: 1453:individually. 1449: 1446: 1439: 1435: 1432: 1430: 1427: 1425: 1422: 1420: 1417: 1415: 1412: 1410: 1407: 1406: 1402: 1396: 1391: 1388: 1377: 1372: 1369: 1365: 1357: 1354: 1346: 1344: 1342: 1338: 1334: 1330: 1326: 1322: 1321:justification 1318: 1314: 1310: 1304: 1300: 1292: 1288: 1285: 1283: 1280: 1278: 1275: 1273: 1270: 1268: 1267:Löb's theorem 1265: 1263: 1260: 1258: 1255: 1253: 1250: 1248: 1245: 1243: 1240: 1238: 1235: 1234: 1233: 1230: 1228: 1227: 1222: 1218: 1212: 1210: 1206: 1202: 1197: 1195: 1191: 1187: 1182: 1179: 1171: 1167: 1163: 1159: 1155: 1151: 1146: 1142: 1128: 1120: 1104: 1096: 1092: 1088: 1084: 1080: 1079:formal theory 1076: 1068: 1066: 1064: 1059: 1054: 1052: 1048: 1044: 1040: 1036: 1031: 1025: 1023: 1019: 1016: 1011: 1009: 1005: 1000: 998: 994: 990: 986: 979: 976: 974: 971: 969: 966: 964: 960: 957: 954: 951: 950: 949: 943: 941: 939: 935: 931: 923: 919: 915: 911: 907: 903: 899: 898: 893: 892: 887: 884: 883:Cramer's rule 880: 876: 872: 869: 865: 861: 857: 856: 851: 850: 849: 843: 839: 835: 834: 829: 826: 822: 821: 816: 812: 808: 804: 803: 798: 795: 791: 787: 786:Gauss's lemma 783: 779: 778: 773: 763: 762: 757: 753: 749: 748: 743: 740: 736: 733: 729: 725: 721: 717: 713: 709: 708: 703: 700: 696: 692: 691: 686: 682: 681: 676: 675: 674: 667: 665: 663: 659: 654: 652: 648: 644: 640: 636: 632: 628: 624: 619: 617: 616:zeta function 613: 609: 605: 601: 596: 589: 585: 581: 577: 572: 568: 566: 562: 558: 550: 548: 545: 541: 536: 534: 533:combinatorics 530: 529:number theory 526: 522: 514: 510: 505: 501: 499: 495: 489: 485: 483: 479: 475: 471: 467: 463: 462: 457: 456: 451: 447: 443: 439: 435: 431: 427: 423: 419: 415: 411: 407: 403: 399: 395: 391: 387: 380: 378: 376: 372: 367: 365: 359: 357: 352: 350: 346: 342: 338: 334: 326: 324: 322: 318: 314: 310: 306: 301: 297: 295: 291: 287: 285: 279: 275: 271: 267: 263: 258: 256: 252: 248: 244: 239: 237: 233: 229: 225: 221: 217: 213: 209: 201: 199: 197: 196: 191: 187: 186: 181: 177: 172: 170: 166: 162: 158: 154: 150: 146: 142: 138: 134: 129: 127: 123: 119: 115: 111: 107: 103: 98: 96: 92: 88: 84: 80: 76: 72: 68: 64: 60: 52: 47: 41: 37: 33: 19: 4239: 4037:Ultraproduct 3884:Model theory 3849:Independence 3809: 3785:Formal proof 3777:Proof theory 3760: 3733: 3690:real numbers 3662:second-order 3573:Substitution 3450:Metalanguage 3391:conservative 3364:Axiom schema 3308:Constructive 3278:Morse–Kelley 3244:Set theories 3223:Aleph number 3216:inaccessible 3122:Grothendieck 3006:intersection 2893:Higher-order 2881:Second-order 2827:Truth tables 2784:Venn diagram 2601: 2567:Formal proof 2474: 2458: 2454:formal proof 2362: 2347: 2312: 2303: 2283: 2273: 2252: 2238: 2219: 2208:Model Theory 2207: 2185: 2176: 2167: 2156:. Retrieved 2150: 2137: 2128: 2119: 2100: 2091: 2082: 2073: 2064: 2055: 2046: 2037: 2028: 2019: 2007: 1998: 1989: 1977:. Retrieved 1973: 1964: 1955: 1945: 1938: 1929: 1878: 1870:"Opinion 51" 1860: 1848: 1835: 1824:. Retrieved 1820: 1811: 1800:. Retrieved 1796: 1769:. Retrieved 1765: 1755: 1738: 1728:, retrieved 1723: 1675: 1671: 1665: 1640: 1636: 1630: 1619:. Retrieved 1615:the original 1610: 1601: 1590:. Retrieved 1586: 1577: 1565:. Retrieved 1551: 1538: 1507: 1502: 1492: 1479: 1458: 1448: 1308: 1306: 1231: 1224: 1220: 1216: 1213: 1205:model theory 1201:proof theory 1198: 1194:inconsistent 1183: 1175: 1072: 1061:type is the 1055: 1043:AlfrĂ©d RĂ©nyi 1032: 1029: 1020: 1012: 1001: 988: 982: 977: 972: 967: 962: 958: 952: 947: 927: 895: 889: 874: 853: 847: 841: 838:special case 831: 825:right angles 818: 815:right angles 807:special case 800: 790:Zorn's lemma 781: 775: 760: 745: 738: 727: 719: 718:). 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The 1051:number 1004:macros 985:Q.E.D. 944:Layout 916:, the 862:(e.g. 860:domain 820:square 792:, and 756:Euclid 647:googol 509:planar 494:axioms 274:axioms 224:axioms 153:axioms 149:theory 95:axioms 75:proven 40:Theory 3909:Model 3657:Peano 3514:Proof 3354:Arity 3283:Naive 3170:image 3102:Fuzzy 3062:Empty 3011:union 2956:Class 2597:Model 2587:Lemma 2545:Axiom 2479:false 2284:A = B 1793:(PDF) 1698:S2CID 1680:arXiv 1653:S2CID 1548:(PDF) 1440:Notes 1217:about 968:Proof 777:lemma 680:axiom 660:(see 268:of a 234:of a 118:lemma 79:proof 69:is a 38:, or 4032:Type 3835:list 3639:list 3616:list 3605:Term 3539:rank 3433:open 3327:list 3139:Maps 3044:sets 2903:Free 2873:list 2623:list 2550:list 2289:ISBN 2259:ISBN 2224:ISBN 2193:ISBN 1981:2019 1518:, a 1366:and 1301:and 1168:and 1160:and 1077:, a 1056:The 1026:Lore 881:and 875:rule 866:and 823:are 813:are 714:and 574:The 531:and 448:and 424:the 276:and 251:sets 216:line 192:. A 147:. A 124:and 65:, a 61:and 49:The 3719:of 3701:of 3649:of 3181:Sur 3155:Map 2962:Ur- 2944:Set 1890:tan 1690:doi 1645:doi 1508:law 1141:). 1073:In 978:End 894:or 891:law 852:An 844:). 840:(a 758:'s 683:or 677:An 432:or 364:why 351:). 335:or 222:or 131:In 57:In 4264:: 4105:NP 3729:: 3723:: 3653:: 3330:), 3185:Bi 3177:In 2346:. 1972:. 1868:. 1847:. 1819:. 1795:. 1780:^ 1764:. 1710:^ 1696:. 1688:. 1676:16 1674:. 1651:. 1641:13 1639:. 1609:. 1585:. 1556:. 1550:. 1319:, 1229:. 1211:. 1037:, 1010:. 940:. 932:, 924:). 912:, 908:, 904:, 888:A 885:). 873:A 870:). 830:A 799:A 796:). 788:, 774:A 766:c. 744:A 737:A 704:A 653:. 507:A 392:: 323:. 120:, 34:, 4185:/ 4100:P 3855:) 3641:) 3637:( 3534:∀ 3529:! 3524:∃ 3485:= 3480:↔ 3475:→ 3470:∧ 3465:√ 3460:ÂŹ 3183:/ 3179:/ 3153:/ 2964:) 2960:( 2847:∞ 2837:3 2625:) 2523:e 2516:t 2509:v 2475:⊄ 2396:‌ 2389:e 2382:t 2375:v 2352:. 2297:. 2267:. 2232:. 2201:. 2161:. 1983:. 1924:. 1908:) 1902:+ 1896:( 1872:. 1853:. 1829:. 1805:. 1774:. 1704:. 1692:: 1682:: 1659:. 1647:: 1624:. 1595:. 1570:. 1522:. 1487:. 987:( 963:) 764:( 639:n 635:n 633:( 631:M 627:n 590:. 482:n 478:n 474:n 466:n 450:B 446:A 422:B 410:A 406:A 402:B 398:B 42:. 20:)

Index

Theorems
Teorema
Theorema
Theory

Pythagorean theorem
mathematics
formal logic
statement
proven
logical argument
deductive system
logical consequence
axioms
Zermelo–Fraenkel set theory
axiom of choice
Peano arithmetic
mathematical logic
formalized
well-formed formulas
formal language
theory
proof theory
Gödel's incompleteness theorems
consistent
physical world
scientific law
experimental
deductive
conjecture

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