• In mathematical logic, second-order arithmetic is a collection of axiomatic systems that formalize the natural numbers and their subsets. It is an alternative...
    29 KB (3,837 words) - 20:00, 4 July 2025
  • second-order arithmetic. Just as in first-order logic, second-order logic may include non-logical symbols in a particular second-order language. These...
    32 KB (4,502 words) - 01:10, 13 April 2025
  • of arithmetic in second order logic that is called second order arithmetic. It has only one model, unlike the corresponding theory in first-order logic...
    36 KB (5,269 words) - 20:51, 27 December 2024
  • the second-order and first-order formulations, as discussed in the section § Peano arithmetic as first-order theory below. If we use the second-order induction...
    49 KB (6,478 words) - 19:26, 19 July 2025
  • Reverse mathematics is usually carried out using subsystems of second-order arithmetic, where many of its definitions and methods are inspired by previous...
    38 KB (4,782 words) - 10:20, 2 June 2025
  • includes quadratic terms Second-order arithmetic, an axiomatization allowing quantification of sets of numbers Second-order differential equation, a differential...
    1 KB (198 words) - 17:14, 12 December 2022
  • In mathematical logic, true arithmetic is the set of all true first-order statements about the arithmetic of natural numbers. This is the theory associated...
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  • theorem, is undecidable in (first-order) Peano arithmetic, but can be proved in the stronger system of second-order arithmetic. Kirby and Paris later showed...
    92 KB (12,171 words) - 07:16, 2 August 2025
  • Thumbnail for Arithmetical hierarchy
    In mathematical logic, the arithmetical hierarchy, arithmetic hierarchy or Kleene–Mostowski hierarchy (after mathematicians Stephen Cole Kleene and Andrzej...
    25 KB (4,585 words) - 15:57, 20 July 2025
  • stated that the axioms he considered for arithmetic were the ones given in Hilbert (1900), which include a second order completeness axiom. In the 1930s, Kurt...
    15 KB (1,500 words) - 01:07, 19 March 2024
  • second-order arithmetic in the sense that each of the statements can be derived from each other in the weak system of primitive recursive arithmetic (PRA)...
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  • Thumbnail for Gottlob Frege
    ∀x(Fx ↔ Gx). V* is consistent if second-order arithmetic is, and suffices to prove the axioms of second-order arithmetic. Basic Law V can simply be replaced...
    49 KB (5,405 words) - 19:23, 30 July 2025
  • Presburger arithmetic is the first-order theory of the natural numbers with addition, named in honor of Mojżesz Presburger, who introduced it in 1929...
    25 KB (3,274 words) - 10:14, 1 August 2025
  • an analogue of the axiom of constructibility for subsystems of second-order arithmetic. A few results stand out in the study of such analogues: John Addison's...
    8 KB (1,064 words) - 19:30, 6 July 2025
  • of second-order arithmetic and reverse mathematics. The field of proof theory includes the study of second-order arithmetic and Peano arithmetic, as...
    54 KB (6,414 words) - 03:45, 30 May 2025
  • the syntax of formal logic within first-order arithmetic. Each expression of the formal language of arithmetic is assigned a distinct number. This procedure...
    16 KB (2,271 words) - 22:09, 28 July 2025
  • extension of the arithmetical hierarchy. The analytical hierarchy of formulas includes formulas in the language of second-order arithmetic, which can have...
    10 KB (1,668 words) - 16:23, 24 June 2024
  • Kruskal's tree theorem (category Order theory)
    a statement that cannot be proved in ATR0 (a second-order arithmetic theory with a form of arithmetical transfinite recursion). In 2004, the result was...
    14 KB (1,642 words) - 16:05, 18 June 2025
  • that HP and suitable definitions of arithmetical notions entail all axioms of what we now call second-order arithmetic. This result is known as Frege's theorem...
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  • Peano Arithmetic using transfinite induction up to ordinal ε0. Ordinal analysis has been extended to many fragments of first and second order arithmetic and...
    20 KB (2,669 words) - 20:58, 24 July 2025
  • first-order logic. A theory about a topic, such as set theory, a theory for groups, or a formal theory of arithmetic, is usually a first-order logic together...
    93 KB (12,955 words) - 02:36, 20 July 2025
  • transfinite induction of arithmetical statements for R {\displaystyle R} . Some theories, such as subsystems of second-order arithmetic, have no conceptualization...
    52 KB (4,962 words) - 00:50, 20 June 2025
  • are still fairly significant (in ascending order): The proof-theoretic ordinal of second-order arithmetic. A possible limit of Taranovsky's C ordinal...
    40 KB (5,535 words) - 09:31, 31 July 2025
  • Thumbnail for Kőnig's lemma
    suitable vertex. In this case, Kőnig's lemma is provable in second-order arithmetic with arithmetical comprehension, and, a fortiori, in ZF set theory (without...
    17 KB (2,344 words) - 22:12, 26 February 2025
  • that it is unprovable in Peano arithmetic (but it can be proven in stronger systems, such as second-order arithmetic or Zermelo-Fraenkel set theory)...
    23 KB (2,974 words) - 07:39, 23 April 2025
  • In mathematics, Robinson arithmetic is a finitely axiomatized fragment of first-order Peano arithmetic (PA), first set out by Raphael M. Robinson in 1950...
    15 KB (1,836 words) - 18:59, 27 July 2025
  • elementary function arithmetic (EFA), also called elementary arithmetic and exponential function arithmetic, is the system of arithmetic with the usual elementary...
    7 KB (875 words) - 20:48, 17 February 2025
  • Turing computability. It has close connections with definability in second-order arithmetic and with weak systems of set theory such as Kripke–Platek set theory...
    14 KB (2,292 words) - 15:00, 2 April 2024
  • be proven in much weaker systems than ZFC, such as Peano arithmetic and second-order arithmetic (as explored by the program of reverse mathematics). Saunders...
    46 KB (6,282 words) - 01:47, 21 July 2025
  • 1939, it presents fundamental mathematical ideas and introduced second-order arithmetic. 1934/1939 (Vol. I, II) First German edition, Springer 1944 Reprint...
    5 KB (438 words) - 09:19, 26 June 2024