Abstract
Predicativity is a notable example of fruitful interaction between philosophy and mathematical logic. It originated at the beginning of the 20th century from methodological and philosophical reflections on a changing concept of set. A clarification of this notion has prompted the development of fundamental new technical instruments, from Russell’s type theory to an important chapter in proof theory, which saw the decisive involvement of Kreisel, Feferman and Schütte. The technical outcomes of predicativity have since taken a life of their own, but have also produced a deeper understanding of the notion of predicativity, therefore witnessing the “light logic throws on problems in the foundations of mathematics.” [30, p. vii] Predicativity has been at the center of a considerable part of Feferman’s work: over the years he has explored alternative ways of explicating and analyzing this notion and has shown that predicative mathematics extends much further than expected within ordinary mathematics. The aim of this note is to outline the principal features of predicativity, from its original motivations at the start of the past century to its logical analysis in the 1950–1960s. The hope is to convey why predicativity is a fascinating subject, which has attracted Feferman’s attention over the years.
Dedicated to Professor Solomon Feferman
I thank Andrea Cantini for helpful comments on a draft of this article. I also profited from remarks by Gerhard Jäger and Wilfried Sieg, as well as two anonymous referees. I gratefully acknowledge funding from the School of Philosophy, Religion and History of Science of the University of Leeds and from the European Research Council under the European Union’s Seventh Framework Programme (FP/2007–2013)/ERC Grant Agreement n. 312938.
Similar content being viewed by others
Notes
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
Feferman [34] writes: “Though early discussions are often muddy on the concepts and their employment, in a number of important respects they set the stage for the further developments, and so I shall give them special attention.”
- 7.
In his introduction to a chapter on the ordinal analysis of predicativity, Pohlers [68, p. 134] writes: “The notion of predicativity is still controversial. Therefore we define and discuss here predicativity in a pure mathematical – and perhaps oversimplified – setting.” See [22, 50, 55, 56, 96] for discussions pertaining to the logical analysis of predicativity. See also the discussion on “metapredicativity” in [52]. As to the philosophical and historical aspects of predicativity, see, e.g., [32, 37, 48, 59, 65,66,67].
- 8.
Predicativity-related themes have appeared in different forms over the years, both in classical and constructive settings. In fact, predicativity is gaining renewed prominence today especially in the constructive context. I shall postpone to another occasion a discussion of other forms of predicativity, as the constructive predicativity which characterizes Martin-Löf type theory see, e.g., [60,61,62] and forms of “strict predicativity” [64, 65, 67]. See also [11, 12].
- 9.
In the following, I shall also write “predicativity” to denote predicativity given the natural numbers. See Sect. 3.4 for some remarks on the notion of predicativity given the natural numbers.
- 10.
- 11.
- 12.
See [69,70,71, 81, 82]. Note that the term “class” is used here as in Russell and Poincaré’s texts, that is, to refer to a generic collection. Hence it should be carefully distinguished from the notion of proper class that is found in contemporary set theory. In the original literature one frequently finds also the word “totality”. In this section I shall try to avoid the use of the term “set”, since the latter has in the meantime acquired additional connotations (as set in e.g. ZFC) that should not be presupposed in this discussion.
- 13.
See [69,70,71, 80, 81]. See e.g. [47, p. 455] for discussion. Note also that today the distinction between predicative and impredicative definitions is typically framed as relating to sets. However, Russell and Poincaré’s discussions are concerned with definitions of different kinds of entities, including propositions, properties, etc.
- 14.
The issue of how we establish whether an entity is impredicative (and in which context) is more complex than this coarse characterization of impredicativity may suggest. This complexity was further addressed by the development of Russell’s type theory, Weyl’s [97] and the logical analysis of predicativity to be discussed below.
- 15.
Here I shall follow [7, p 48].
- 16.
Carnap [7, p. 48] concludes that this definition of natural number is “circular and useless”. It is worth recalling that Carnap in [7] also hints at a form of platonism, attributed to Ramsey (but not endorsed by Carnap), which finds no fault with impredicative definitions. See also [47, 73] for further discussion.
- 17.
- 18.
- 19.
My translation; italics by Poincaré. The word “disordered” translates the French “bouleverseé”.
- 20.
See [5] for a rich discussion of the impact of the paradoxes on mathematical logic.
- 21.
- 22.
In the present context we may follow [34], and identify the notion of propositional function with that of open formula, i.e. a formula with a free variable, say \(\varphi (x)\). Note, however, that the interpretation of the notions of proposition and propositional function in Russell is complex. See e.g. [57].
- 23.
- 24.
See [49] for a discussion of the reasons that might support Russell’s (and Whitehead’s) choice of a ramified type theory over a simple type theory.
- 25.
- 26.
Russell [82, p. 243] also writes: “Thus a predicative function of an individual is a first-order function; and for higher types of arguments, predicative functions take the place that first-order functions take in respect of individuals. We assume, then, that every function is equivalent, for all its values, to some predicative function of the same argument.”.
- 27.
Wilfried Sieg has informed me about perceptive discussions by Hilbert and Bernays on predicativity and Russell’s logicism, including the axiom of reducibility. See e.g. Hilbert’s lecture notes from 1917/18 entitled “Prinzipien der Mathematik” and those from 1920 entitled “Probleme der mathematischen Logik” published in [15]. See also [87] for discussion. Sieg [87] also draws important correlations between [97] and Hilbert and Bernays’ work around 1920. As suggested by Sieg, the relations between Hilbert and Bernays ’ writings and Weyl’s [97] deserve more thorough investigations.
- 28.
- 29.
Weyl, in particular, made use of sequential rather than Dedekind completeness, the first being amenable to predicative treatment. See also [26].
- 30.
In addition to properties, Weyl [97] also considers relations, here omitted for simplicity.
- 31.
The notion of “judgment” is so clarified by Weyl [97, p. 5]: a “judgment affirms a state of affairs”.
- 32.
Weyl also considers a principle of substitution [97, p. 10]. In addition, in the paradigmatic case of the natural numbers as basic domain, one also applies a principle of iteration, as further discussed below.
- 33.
As remarked by Feferman [26] see also [31], it is not completely clear how strong is the system Weyl sketches in [97]. Feferman has, however, verified that system W of [26], which is inspired by [97], suffices to carry out all of Weyl’s constructions in “Das Kontinuum”. System W is a conservative extension of Peano Arithmetic, PA [38]. As clarified in Sect. 3.3, Feferman has also shown that W allows for the development of a more extensive portion of contemporary analysis, compared with [97].
- 34.
Poincaré see, e.g., [71] states that mathematical induction is synthetic a priori. Note also that Weyl expresses mathematical induction by appeal to a principle of iteration. See [30, p. 264-5] for discussion. Poincaré and Weyl fully realized the significance of the assumption of unrestricted mathematical induction. This is further clarified by a comparison with approaches to predicativity which instead introduce restrictions on induction [64, 65].
- 35.
- 36.
See also [34] for additional thoughts on what “pushed predicativity to the sidelines.”.
- 37.
- 38.
See also Sect. 3.4 for more on the notion of predicativity given the natural numbers.
- 39.
The use of classical logic marks a crucial difference with the form of predicativity that is to be found in e.g. Martin-Löf type theory [60].
- 40.
The hyperarithmetical hierarchy has a central place in the development of mathematical logic because of its prominence within a number of fundamental areas in mathematical logic: definability theory, recursion theory and admissible set theory. This witnesses the centrality within logic of themes that pertain to the predicativity debate, and further explains the interest of this notion form a logical point of view.
- 41.
In the language of second order arithmetic, a \(\Sigma ^1_1\) formula is one of the form: \(\exists X \, \varphi (X)\), with \(\varphi \) an arithmetical formula, that is, a formula that does not quantify over sets (but may quantify over natural numbers). Note that here the upper case letter X denotes a second order variable, standing for a set of natural numbers. A \(\Pi ^1_1\) formula is one of the form \(\forall X \, \psi (X)\), with \(\psi \) an arithmetical formula.
- 42.
- 43.
See also [95].
- 44.
See also the review by Gandy [44].
- 45.
Here ordinals are not to be considered set-theoretically, rather as notations from a suitable ordinal notation system. See [68] for details on ordinal notation systems.
- 46.
See e.g. [68, Ch. 1] for details. In the branch of proof theory known as ordinal analysis, suitable (countable) ordinals, termed “proof-theoretic ordinals”, are assigned to theories as a way of measuring their consistency strength and computational power. The “proof-theoretic strength” of a theory is then expressed in terms of such ordinals. The countable ordinal \(\Gamma _0\) is the proof-theoretic ordinal assigned to the progression of ramified systems mentioned above. It is relatively small in proof-theoretic terms. As a way of comparison, it is well above the ordinal \(\epsilon _0\) which encapsulates the proof-theoretic strength of Peano Arithmetic, but it is much smaller than the ordinal assigned to a well–known theory, called \({ ID}_1\), of one inductive definition. The latter ordinal is known in the literature as the Bachmann–Howard ordinal [3]. The strength of \({ ID}_1\) is well below that of second order arithmetic, which is in turn much weaker than full set theory. For surveys on proof theory and ordinal analysis see, for example, [76,77,78].
- 47.
See [50, p. 283] for discussion.
- 48.
- 49.
- 50.
The expression “ordinary mathematics” refers to mainstream mathematics, and has been so characterized, for example, by Simpson [89, p. 1]: “that body of mathematics which is prior to or independent of the introduction of abstract set-theoretic concepts”. That is: “geometry, number theory, calculus, differential equations, real and complex analysis, countable algebra, the topology of complete separable metric spaces, mathematical logic and computability theory”.
- 51.
- 52.
- 53.
Note that Feferman draws different conclusions on the impact of the logical research on indispensability arguments in the philosophy of mathematics [28].
- 54.
In the following I shall often omit explicit reference to the unrestricted principle of mathematical induction, and simply write “the natural numbers”; however, I shall presuppose that in the case of predicativity given the natural numbers full induction is also assumed.
- 55.
Feferman [16, 34] also describes the predicativist position as one that takes the natural numbers as a “completed totality”, and views the rest in potentialist terms. However, I could find no further elucidation of the notion of complete totality, beyond the claim that we can use classical logic to reason about it. In [32, 35], Feferman proposes to read the “giveness” of the natural numbers in terms of realism in truth value (restricted to the natural numbers). A fundamental theme that emerges within Feferman’s discussions on predicativity is an opposition, analogous to Weyl’s, to arbitrary sets, and in particular to the powerset of an infinite set (see e.g., [33]).
- 56.
- 57.
Wilfried Sieg has drawn my attention to a passage in Hilbert’s 1920s lectures [15, p. 363-4] which suggests that this view of predicativity is in agreement with a Hilbertian perspective. It is also worth observing that with the shift of the logical analysis of predicativity to proof-theoretic considerations this enterprise gained a clear Hilbertian character.
References
Benacerraf, P., Putnam, H.: Philosophy of Mathematics: Selected Readings. Cambridge University Press, Cambridge (1983)
Bernays, P.: Sur the platonisme dans les mathématiques. L’Enseignement mathématique 34, 52–69 (1935). Translated in [1] with the title: On Platonism in Mathematics
Buchholz, W., Feferman, S., Pohlers, W., Sieg, W.: Iterated Inductive Definitions and Subsystems of Analysis. Springer, Berlin (1981)
Cantini, A.: Una teoria della predicatività secondo Poincaré. Rivista di Filosofia 72, 32–50 (1981)
Cantini, A.: Paradoxes, self-reference and truth in the 20th century. In: Gabbay, D. (ed.) The Handbook of the History of Logic, pp. 5–875. Elsevier (2009)
Cantini, A., Fujimoto, K., Halbach, F.: Feferman and the Truth, this volume (2017)
Carnap, R.: Die Logizistische Grundlegung der Mathematik. Erkenntnis 2(1), 91–105 (1931). Translated in [1]. (Page references are to the translation)
Church, A.: A formulation of the simple theory of types. J. Symb. Logic 5, 56–68 (1940)
Chwistek, L.: Über die Antinomien der Prinzipien der Mathematik. Mathematische Zeitschrift 14, 236–43 (1922)
Coquand, T.: Type theory. In: Zalta, E.N. (ed.) The Stanford Encyclopedia of Philosophy (2015)
Crosilla, L.: Constructive and intuitionistic ZF. In: Zalta, E.N. (ed.) Stanford Encyclopedia of Philosophy (2014). http://plato.stanford.edu/entries/set-theory-constructive/
Crosilla, L.: Error and predicativity. In: Beckmann, A., Mitrana, V., Soskova, M. (eds.) Evolving Computability. Lecture Notes in Computer Science, vol. 9136, pp. 13–22. Springer International Publishing (2015)
Dummett, M.: Frege: Philosophy of Mathematics. Harvard University Press, Cambridge (1991)
Dummett, M.: What is mathematics about? In: George, A. (ed.) The Seas of Language, pp. 429–445. Oxford University Press (1993). Reprinted in [51], pp. 19–30
Ewald, W., Sieg, W.: David Hilbert’s Lectures on the Foundations of Arithmetic and Logic, 1917–1933. Springer, Heidelberg (2013)
Feferman, S.: Systems of predicative analysis. J. Symb. Logic 29, 1–30 (1964)
Feferman, S.: Predicative provability in set theory. Bull. Am. Math. Soc. 72, 486–489 (1966)
Feferman, S.: Persistent and invariant formulas for outer extensions. Compositio Math. 20, 29–52 (1968)
Feferman, S.: Systems of predicative analysis. II. Representations of ordinals. J. Symb. Logic 33, 193–220 (1968)
Feferman, S.: Predicatively reducible systems of set theory. In: Axiomatic Set Theory (Proceedings of Symposium Pure Mathematics, Vol. XIII, Part II, University California, Los Angeles, California, 1967), pp. 11–32. American Mathematical Society Providence, R.I (1974)
Feferman, S.: Impredicativity of the existence of the largest divisible subgroup of an abelian \(p\)-group. In: Model Theory and Algebra (A Memorial Tribute to Abraham Robinson). Lecture Notes in Mathematics, vol. 498, pp. 117–130. Springer, Berlin (1975)
Feferman, S.: A more perspicuous formal system for predicativity. In: Boffa, M., van Dalen, D., McAloon, K. (eds.) Logic Colloquium ’78’. North Holland, Amsterdam (1979)
Feferman, S.: Iterated inductive fixed-point theories: application to Hancock’s conjecture. In: Patras Logic Symposion (Patras, 1980). Studies in Logic Foundations Mathematics, vol. 109, pp. 171–196. North-Holland, Amsterdam-New York (1982)
Feferman, S.: Proof theory: a personal report. In: Appendix to the Second edition of [94], pp. 447–485 (1987)
Feferman, S.: Hilbert’s program relativized: proof-theoretical and foundational reductions. J. Symb. Logic 53(2), 364–384 (1988)
Feferman, S.: Weyl vindicated: Das Kontinuum seventy years later. In: Cellucci, C., Sambin, G. (eds.) Temi e prospettive della logica e della filosofia della scienza contemporanee, pp. 59–93. CLUEB, Bologna (1988)
Feferman, S.: What rests on what? The proof-theoretic analysis of mathematics. In: Czermak, J. (ed.) Proceedings of the 15th International Wittgenstein Symposium Philosophy of Mathematics, Part I. Verlag Hölder–Pichler– Tempsky, Vienna (1993)
Feferman, S.: Why a little bit goes a long way. Logical foundations of scientifically applicable mathematics. In: PSA 1992, Philosophy of Science Association (East Lansing), vol. 2, pp. 442–455 (1993). Reprinted in [30]
Feferman, S.: Kreisel’s unwinding program. In: Odifreddi, P. (ed.) Kreiseliana, pp. 247–273. About and Around Georg Kreisel, A K Peters (1996)
Feferman, S.: In the Light of Logic. Oxford University Press, New York (1998)
Feferman, S.: The significance of Hermann Weyl’s Das Kontinuum. In: Hendricks, V., Pedersen, S.A., Jørgense, K.F. (eds.) Proof Theory. Kluwer, Dordrecht (2000)
Feferman, S.: Comments on “Predicativity as a philosophical position” by G. Hellman, Rev. Int. Philos. 229(3), 313–323 (2004)
Feferman, S.: The development of programs for the foundations of mathematics in the first third of the 20th century. In: Petruccioli, S. (ed.) Storia della scienza. Istituto della Enciclopedia Italiana, vol. 8, pp. 112–121. Translated as Le scuole di filosofia della matematica (2004)
Feferman, S.: Predicativity. In: Shapiro, S. (ed.) Handbook of the Philosophy of Mathematics and Logic. Oxford University Press, Oxford (2005)
Feferman, S.: Conceptions of the continuum. Intellectica 51, 169–189 (2009)
Feferman, S. 2013 , Why a little bit goes a long way: predicative foundations of analysis. Unpublished notes dating from 1977-1981, with a new introduction. Retrieved from the address: https://math.stanford.edu/\(\sim \)feferman/papers.html
Feferman, S., Hellman, G.: Predicative foundations of arithmetic. J. Philos. Logic 22, 1–17 (1995)
Feferman, S., Jäger, G.: Systems of explicit mathematics with non-constructive \(\mu \)-operator, Part I. Ann. Pure Appl. Logic 65(3), 243–263 (1993)
Feferman, S., Kreisel, G.: Persistent and invariant formulas relative to theories of higher order. Bull. Am. Math. Soc. 72, 480–485 (1966)
Feferman, S., Strahm, T.: The unfolding of non-finitist arithmetic. Ann. Pure Appl. Logic 104(1–3), 75–96 (2000)
Feferman, S., Strahm, T.: Unfolding finitist arithmetic. Rev. Symb. Logic 3(4), 665–689 (2010)
Ferreirós, J.: On arbitrary sets and ZFC. Bull. Symb. Logic (3) 2011
Friedman, H.: Systems of second order arithmetic with restricted induction, I, II (abstracts). J. Symb. Logic 41, 557–559 (1976)
Gandy, R.O.: Review of [16]. Math. Rev. (1967)
Gödel, K.: The consistency of the axiom of choice and of the generalized continuum-hypothesis. Proc. Natl. Acad. Sci. U. S. A. 24, 556–557 (1938)
Gödel, K.: The Consistency of the Axiom of Choice and of the Generalized Continuum-Hypothesis with the Axioms of Set Theory, vol. 17. Princeton University Press (1940)
Gödel, K.: Russell’s mathematical logic. In: Schlipp, P.A. (ed.) The philosophy of Bertrand Russell, pp. 123–153. Northwestern University, Evanston and Chicago (1944). Reprinted in [1]. Page references are to the reprinting
Hellman, G.: Predicativism as a philosophical position. Revue Internationale de Philosophie 3, 295–312 (2004)
Hodes, H.T.: Why ramify? Notre Dame J. Formal Logic 56(2), 379–415 (2015)
Howard, W.A.: Some Proof Theory in the 1960’s. In: Odifreddi, P. (ed.) ‘Kreiseliana. About and Around Georg Kreisel’, pp. 274–288. A K Peters (1996)
Jacquette, D. (ed.): Philosophy of Mathematics: An Anthology. Wiley-Blackwell (2001)
Jäger, G.: Metapredicative and explicit Mahlo: a proof-theoretic perspective. In: R. Cori et al. (ed.) Proceedings of Logic Colloquium 2000. Association of Symbolic Logic Lecture Notes in Logic, vol. 19, pp. 272–293. AK Peters (2005)
Kleene, S.C.: Quantification of number-theoretic functions. Compositio Mathematica 14, 23–40 (1959)
Kreisel, G.: Ordinal logics and the characterization of informal concepts of proof. In: Proceedings of the International Congress of Mathematicians (August 1958), pp. 289–299. Gauthier–Villars, Paris (1958)
Kreisel, G.: La prédicativité. Bulletin de la Societé Mathématique de France 88, 371–391 (1960)
Kreisel, G.: Principles of proof and ordinals implicit in given concepts. In: Kino, R.E.V.A., Myhill, J. (eds.) Intuitionism and Proof Theory, pp. 489–516. North-Holland, Amsterdam (1970)
Linsky, B.: Propositional functions and universals in principia mathematica. Austr. J. Philos. 66(4), 447–460 (1988)
Maddy, P.: Naturalism in Mathematics. Oxford University Press, Oxford (1997)
Mancosu, P.: From Brouwer to Hilbert. The Debate on the Foundations of Mathematics in the 1920s. Oxford University Press, Oxford (1998)
Martin-Löf, P.: An intuitionistic theory of types: predicative part. In: Rose, H.E., Shepherdson, J.C. (eds.), Logic Colloquium 1973. North–Holland, Amsterdam (1975)
Martin-Löf, P.: Intuitionistic Type Theory. Bibliopolis, Naples (1984)
Martin-Löf, P.: The Hilbert–Brouwer controversy resolved? In: van Atten, E.A. (ed.) One Hundred Years of Intuitionism (1907 – 2007), Publications des Archives Henri Poincaré, pp. 243–256 (2008)
Myhill, J.: The undefinability of the set of natural numbers in the ramified principia. In: Nakhnikian, G. (ed.) Bertrand Russell’s Philosophy, pp. 19–27. Duckworth, London (1974)
Nelson, E.: Predicative Arithmetic. Princeton University Press, Princeton (1986)
Parsons, C.: The impredicativity of induction. In: Detlefsen, M. (ed.) Proof, Logic, and Formalization, pp. 139–161. Routledge, London (1992)
Parsons, C.: Realism and the debate on impredicativity, 1917–1944. Association for Symbolic Logic (2002)
Parsons, C.: Mathematical Thought and Its Objects. Cambridge University Press, Cambridge (2008)
Pohlers, W.: Proof Theory: The First Step into Impredicativity, Universitext. Springer, Berlin (2009)
Poincaré, H.: Les mathématiques et la logique. Revue de Métaphysique et Morale 13, 815–835 (1905)
Poincaré, H.: Les mathématiques et la logique. Revue de Métaphysique et de Morale 14, 17–34 (1906)
Poincaré, H.: Les mathématiques et la logique. Revue de Métaphysique et de Morale 14, 294–317 (1906)
Poincaré, H.: La logique de l’infini. Revue de Métaphysique et Morale 17, 461–482 (1909)
Poincaré, H.: La logique de l’infini. Scientia 12, 1–11 (1912)
Ramsey, F.P.: Foundations of mathematics. Proc. Lond. Math. Soc.25 (1926). Reprinted in [75]
Ramsey, F.P.: Foundations of Mathematics and Other Logical Essays. Routledge and Kegan Paul (1931)
Rathjen, M.: The higher infinite in proof theory. In: Makowsky, J.A., Ravve, E.V. (eds.) Logic Colloquium ’95’. Springer Lecture Notes in Logic, vol. 11. Springer, New York, Berlin (1998)
Rathjen, M.: The realm of ordinal analysis. In: Sets and proofs (Leeds, 1997). London Mathematical Society Lecture Note Series, vol. 258, pp. 219–279. Cambridge Univ. Press, Cambridge (1999)
Rathjen, M.: Theories and ordinals in proof theory. Synthese 148(3), 719–743 (2006)
Russell, B.: The Principles of Mathematics. Routledge (1903)
Russell, B.: ‘Les paradoxes de la logique’. Revue de métaphysique et de morale 14, 627–650 (1906)
Russell, B.: On some difficulties in the theory of transfinite numbers and order types. Proc. Lond. Math. Soc. 4, 29–53 (1906)
Russell, B.: Mathematical logic as based on the theory of types. Am. J. Math. 30, 222–262 (1908)
Russell, B.: Essays in Analysis. In: Lackey, D. (ed.). George Braziller, New York (1973)
Sacks, G.E.: Perspectives in Mathematical Logic. Higher recursion theory. Springer, Berlin (1990)
Schütte, K.: Eine Grenze für die Beweisbarkeit der Transfiniten Induktion in der verzweigten Typenlogik. Archiv für mathematische Logik und Grundlagenforschung 7, 45–60 (1965)
Schütte, K.: Predicative well–orderings. In: Crossley, J., Dummett, M. (eds.) Formal Systems and Recursive Functions. North–Holland, Amsterdam (1965)
Sieg, W.: Hilbert’s programs: 1917–1922. Bull. Symb. Logic 5(1), 1–44 (1999)
Simpson, S.G.: Partial realizations of Hilbert’s program. J. Symb. Logic 53(2), 349–363 (1988)
Simpson, S.G.: Subsystems of Second Order Arithmetic. Perspectives in Mathematical Logic. Springer, Berlin (1999)
Simpson, S.G.: Predicativity: the outer limits. In: Reflections on the foundations of mathematics (Stanford, CA, 1998). Lecture Notes Logic 15, Assoc. Symbol. Logic, Urbana, IL, 130–136 (2002)
Spector, C.: Recursive well-orderings. J. Symb. Logic 20, 151–163 (1955)
Stein, H.: Logos, logic and logistiké. In: Asprey, W., Kitcher, P. (eds.) History and Philosophy of Modern Mathematics, pp. 238–59. University of Minnesota, Minneapolis (1988)
Strahm, T.: Unfolding schematic systems, this volume (2017)
Takeuti, G.: Proof Theory, 2nd edn. North Holland, Amsterdam (1987)
Wang, H.: The formalization of mathematics. J.Symb. Logic 19(4), 241–266 (1954)
Weaver, N.: Predicativity beyond \({\Gamma }_0\) (2005). Preprint submitted to the arXiv repository: arXiv:math/0509244
Weyl, H.: Das Kontinuum: Kritische Untersuchungen über die Grundlagen der Analysis, Veit, Leipzig. Translated in English, Dover Books on Mathematics, 2003. (Page references are to the translation) (1918)
Weyl, H.: Philosophy of Mathematics and Natural Science. Princeton University Press (1949). An expanded English version of Philosophie der Mathematik und Naturwissenschaft, München, Leibniz Verlag (1927)
Whitehead, A.N., Russell, B.: Principia Mathematica, 3 Vols. Cambridge University Press, Cambridge (1910, 1912, 1913); 2nd edn (1925) (Vol 1), 1927 (Vols 2, 3); abridged as Principia Mathematica to *56. Cambridge University Press, Cambridge (1962)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2017 Springer International Publishing AG, part of Springer Nature
About this chapter
Cite this chapter
Crosilla, L. (2017). Predicativity and Feferman. In: Jäger, G., Sieg, W. (eds) Feferman on Foundations. Outstanding Contributions to Logic, vol 13. Springer, Cham. https://doi.org/10.1007/978-3-319-63334-3_15
Download citation
DOI: https://doi.org/10.1007/978-3-319-63334-3_15
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-63332-9
Online ISBN: 978-3-319-63334-3
eBook Packages: Mathematics and StatisticsMathematics and Statistics (R0)