According to the implicit commitment thesis, once accepting a mathematical formal system S, one is implicitly committed to additional resources not immediately available in S. Traditionally, this thesis has been understood as entailing that, in accepting S, we are bound to accept reflection principles for S and therefore claims in the language of S that are not derivable in S itself. It has recently become clear, however, that such reading of the implicit commitment thesis cannot be compatible with well-established positions (...) in the foundations of mathematics which consider a specific theory S as self-justifying and doubt the legitimacy of any principle that is not derivable in S: examples are Tait’s finitism and the role played in it by Primitive Recursive Arithmetic, Isaacson’s thesis and Peano Arithmetic, Nelson’s ultrafinitism and sub-exponential arithmetical systems. This casts doubts on the very adequacy of the implicit commitment thesis for arithmetical theories. In the paper we show that such foundational standpoints are nonetheless compatible with the implicit commitment thesis. We also show that they can even be compatible with genuine soundness extensions of S with suitable form of reflection. The analysis we propose is as follows: when accepting a system S, we are bound to accept a fixed set of principles extending S and expressing minimal soundness requirements for S, such as the fact that the non-logical axioms of S are true. We call this invariant component the semantic core of implicit commitment. But there is also a variable component of implicit commitment that crucially depends on the justification given for our acceptance of S in which, for instance, may or may not appear reflection principles for S. We claim that the proposed framework regulates in a natural and uniform way our acceptance of different arithmetical theories. (shrink)

We discuss the principles for a primitive, object-linguistic notion of consequence proposed by ) that yield a version of Curry’s paradox. We propose and study several strategies to weaken these principles and overcome paradox: all these strategies are based on the intuition that the object-linguistic consequence predicate internalizes whichever meta-linguistic notion of consequence we accept in the first place. To these solutions will correspond different conceptions of consequence. In one possible reading of these principles, they give rise to a notion (...) of logical consequence: we study the corresponding theory of validity by showing that it is conservative over a wide range of base theories: this result is achieved via a well-behaved form of local reduction. The theory of logical consequence is based on a restriction of the introduction rule for the consequence predicate. To unrestrictedly maintain this principle, we develop a conception of object-linguistic consequence, which we call grounded consequence, that displays a restriction of the structural rule of reflexivity. This construction is obtained by generalizing Saul Kripke’s inductive theory of truth. Grounded validity will be shown to satisfy several desirable principles for a naïve, self-applicable notion of consequence. (shrink)

In the paper we investigate typed axiomatizations of the truth predicate in which the axioms of truth come with a built-in, minimal and self-sufficient machinery to talk about syntactic aspects of an arbitrary base theory. Expanding previous works of the author and building on recent works of Albert Visser and Richard Heck, we give a precise characterization of these systems by investigating the strict relationships occurring between them, arithmetized model constructions in weak arithmetical systems and suitable set existence axioms. The (...) framework considered will give rise to some methodological remarks on the construction of truth theories and provide us with a privileged point of view to analyze the notion of truth arising from compositional principles in a typed setting. (shrink)

Substructural logics and their application to logical and semantic paradoxes have been extensively studied. In the paper, we study theories of naïve consequence and truth based on a non-reflexive logic. We start by investigating the semantics and the proof-theory of a system based on schematic rules for object-linguistic consequence. We then develop a fully compositional theory of truth and consequence in our non-reflexive framework.

As a response to the semantic and logical paradoxes, theorists often reject some principles of classical logic. However, classical logic is entangled with mathematics, and giving up mathematics is too high a price to pay, even for nonclassical theorists. The so-called recapture theorems come to the rescue. When reasoning with concepts such as truth/class membership/property instantiation, (These are examples of concepts that are taken to satisfy naive rules such as the naive truth schema and naive comprehension, and that therefore are (...) compatible with a solution to paradox cast in the logics considered below. Other notions of similar kind can be added to the list.) if one is interested in consequences of the theory that only contain mathematical vocabulary, nothing is lost by reasoning in the nonclassical framework. This article shows that this claim is highly misleading, if not simply false. Under natural assumptions, some well-established approaches to recapture are incorrect. (shrink)

"Nicolai Hartman ist zu Unrecht vergessen. Wir benötigen eine breite systematische Neubeschäftigung mit seinem großen Entwurf eines realistischen Weltsystems. Im Zeichen der lebenswissenschaftlichen Wende kann man mit seiner überlegenen Darstellung der Teleologie einen Anfang machen." Prof. Dr. Volker Gerhardt, Humboldt Universität zu Berlin.

Drawing on recent phenomenological discussions of collective intentionality and existential phenomenological accounts of agency, this article proposes a novel interpretation of shared action. First, I argue that we should understand action on the basis of how an environment pre-reflectively solicits agents to behave based on (a) the affordances or goals inflected by their abilities and dispositions and (b) their self-referential commitment to a project that is furthered by these affordances. Second, I show that this definition of action is sufficiently flexible (...) to account for not only individual action (in which both (a) and (b) refer only to an individual) but also several distinct subtypes of shared action. My thesis is that behaviour counts as shared action if and only if it is caused by a solicitation in which either (a) the goals, or (b) the commitments, or both (a) goals and (b) commitments are joint, i.e., depend on several individuals. We thereby get three distinct subtypes of shared actions: (i) jointly coordinated individually committed action, (ii) individually coordinated jointly committed action, and (iii) jointly coordinated jointly committed action. (shrink)

Bd. 1. Abhandlungen zur systematischen Philosophie.--Bd. 2. Abhandlungen zur Philosophie-Geschichte.--Bd. 3. Vom Neukantianismus zur Ontologie.

Philosophy &Public Affairs, Volume 51, Issue 2, Page 140-165, Spring 2023.

Name der Zeitschrift: Archiv für Geschichte der Philosophie Jahrgang: 98 Heft: 3 Seiten: 272-301.

This essay reviews two recent volumes containing editions of important early quranic codices. One of these is the so-called Sanaa Palimpsest, whose lower text at present remains our only known material witness to a recension of the quranic text that is different from the canonical one; the other is the Codex Amrensis. The essay devotes particular attention to the question of the textual relationship between the Quran’s standard text and that documented by the lower layer of the Sanaa Palimpsest, and (...) to Asma Hilali’s claim that the Sanaa Palimpsest never constituted a full quranic codex but only “a collection of disparate leaves.”. (shrink)

As a response to the semantic and logical paradoxes, theorists often reject some principles of classical logic. However, classical logic is entangled with mathematics, and giving up mathematics is too high a price to pay, even for nonclassical theorists. The so-called recapture theorems come to the rescue. When reasoning with concepts such as truth/class membership/property instantiation, if ones is interested in consequences of the theory that only contain mathematical vocabulary, nothing is lost by reasoning in the nonclassical framework. It is (...) shown that this claim is highly misleading, if not simply false. Under natural assumptions, recapture claims are incorrect. (shrink)

Truth-theoretic deflationism holds that truth is simple, and yet that it can fulfil many useful logico-linguistic roles. Deflationism focuses on axioms for truth: there is no reduction of the notion of truth to more fundamental ones such as sets or higher-order quantifiers. In this paper I argue that the fundamental properties of reasonable, primitive truth predicates are at odds with the core tenets of classical truth-theoretic deflationism that I call fix, express, and quantify. Truth may be regarded as a broadly (...) logical, sui generis notion. However, this has little to do with the original aims of the deflationary theory of truth. (shrink)

Nicolai Bachman explores the key principles and concepts of yoga philosophy through the Yoga Sutras offering an opportunity to learn and practice the sutras in Sanskrit, revealing the essence of yoga philosophy. The Yoga Sutras is a comprehensive and modern approach to working with Patanjali's seminal text for guidance and inspiration on your own journey toward clarity and happiness.

This title from the De Gruyter Book Archive has been digitized in order to make it available for academic research. It was originally published under National Socialism and has to be viewed in this historical context. Learn more. >.

We study the relationships between two clusters of axiomatizations of Kripke’s fixed-point models for languages containing a self-applicable truth predicate. The first cluster is represented by what we will call ‘\-like’ theories, originating in recent work by Halbach and Horsten, whose axioms and rules are all valid in fixed-point models; the second by ‘\-like’ theories first introduced by Solomon Feferman, that lose this property but reflect the classicality of the metatheory in which Kripke’s construction is carried out. We show that (...) to any natural system in one cluster—corresponding to natural variations on induction schemata—there is a corresponding system in the other proving the same sentences true, addressing a problem left open by Halbach and Horsten and accomplishing a suitably modified version of the project sketched by Reinhardt aiming at an instrumental reading of classical theories of self-applicable truth. (shrink)

In his oration Against Ctesiphon, Aeschines mentions the power his rival Demosthenes had during his term as treasurer of the theoric fund (ἐπὶ τὸ θεωρικόν). Many modern assumptions about the function of the Athenian financial administration and politics between the end of the Social War (357-355 BC) and the early 330’s BC are based on Aischin. Ctes. 25. This article argues for taking into account an emendation brought forward by the early 19 th century British scholar Peter Paul Dobree. His (...) suggestions, as will be shown, correspond better to the rhetorical structure of Aeschines’ argument than the prevailing reading and change the interpretation of the treasurers’ responsibilities. (shrink)

The aim of this volume is to open up new perspectives and to raise new research questions about a unified approach to truth, modalities, and propositional attitudes. The volume's essays are grouped thematically around different research questions. The first theme concerns the tension between the theoretical role of the truth predicate in semantics and its expressive function in language. The second theme of the volume concerns the interaction of truth with modal and doxastic notions. The third theme covers higher-order solutions (...) to the semantic and modal paradoxes, providing an alternative to first-order solutions embraced in the first two themes. This book will be of interest to researchers working in epistemology, logic, philosophy of logic, philosophy of language, philosophy of mathematics, and semantics. (shrink)

This is a translation of Nicolai Hartmann’s article “Der Megarische und der Aristotelische Möglichkeitsbegriff: ein Beitrag zur Geschichte des ontologischen Modalitätsproblems,” first published in 1937. In this article, Hartmann defends an interpretation of the Megarian conception of possibility, which found its clearest form in Diodorus Cronus’ expression of it and according to which “only what is actual is possible” or “something is possible only if it is actual.” Hartmann defends this interpretation against the then dominant Aristotelian conception of possibility, (...) based on the opposition between dynamis and energeia, and according to which there is always an open multiplicity of simultaneous “possibilities,” the outcome of which remains undetermined. Since, according to Hartmann, reality suffers no indetermination, the Megarian conception of possibility is an account of real possibility, whereas the Aristotelian one is merely an account of epistemic possibility. (shrink)

In his 2023 AJOB article, Jorge Fabiano claims that a safety framework is needed to guard against the potential negative consequences of moral enhancement. He describes prudential desiderata that constitute the nodes of his proposed safety framework, ultimately arguing that a virtue theory, as opposed to a non-virtue based theory such as a consequentialist or deontological theory, hues closest to these desiderata. In this open peer commentary (OPC), I argue that Fabiano's trait-based analysis of enhancement-related changes, while illuminating, necessarily commits (...) us to a virtue theoretical framework. (shrink)

The existence of a close connection between results on axiomatic truth and the analysis of truth-theoretic deflationism is nowadays widely recognized. The first attempt to make such link precise can be traced back to the so-called conservativeness argument due to Leon Horsten, Stewart Shapiro and Jeffrey Ketland: by employing standard Gödelian phenomena, they concluded that deflationism is untenable as any adequate theory of truth leads to consequences that were not achievable by the base theory alone. In the paper I highlight, (...) as Shapiro and Ketland, the irreducible nature of truth axioms with respect to their base theories. But, I argue, this does not immediately delineate a notion of truth playing a substantial role in philosophical or scientific explanations. I first offer a refinement of Hartry Field’s reaction to the conservativeness argument by distinguishing between metatheoretic and object-theoretic consequences of the theory of truth and address some possible rejoinders. In the resulting picture, truth is an irreducible tool for metatheoretic ascent. How robust is this characterizaton? I test it by considering: a recent example, due to Leon Horsten, of the alleged explanatory role played by the truth predicate in the derivation of Fitch’s paradox; an essential weakening of theories of truth analyzed in the first part of the paper. (shrink)

There is considerable evidence that listeners’ understanding of a spoken sentence need not always follow from a full analysis of the words and syntax of the utterance. Rather, listeners may instead conduct a superficial analysis, sampling some words and using presumed plausibility to arrive at an understanding of the sentence meaning. Because this latter strategy occurs more often for sentences with complex syntax that place a heavier processing burden on the listener than sentences with simpler syntax, shallow processing may represent (...) a resource conserving strategy reflected in reduced processing effort. This factor may be even more important for older adults who as a group are known to have more limited working memory resources. In the present experiment, 40 older adults and 20 younger adults were tested for comprehension of plausible and implausible sentences with a simpler subject-relative embedded clause structure or a more complex object-relative embedded clause structure. Dilation of the pupil of the eye was recorded as an index of processing effort. Results confirmed greater comprehension accuracy for plausible than implausible sentences, and for sentences with simpler than more complex syntax, with both effects amplified for the older adults. Analysis of peak pupil dilations for implausible sentences revealed a complex three-way interaction between age, syntactic complexity, and plausibility. Results are discussed in terms of models of sentence comprehension, and pupillometry as an index of intentional task engagement. (shrink)

One way to study and understand the notion of truth is to examine principles that we are willing to associate with truth, often because they conform to a pre-theoretical or to a semi-formal characterization of this concept. In comparing different collections of such principles, one requires formally precise notions of inter-theoretic reduction that are also adequate to compare these conceptual aspects. In this work I study possible ways to make precise the relation of conceptual equivalence between notions of truth associated (...) with collections of principles of truth. In doing so, I will consider refinements and strengthenings of the notion of relative truth-definability proposed by Fujimoto (2010): in particular I employ suitable variants of notions of equivalence of theories considered in Visser (2006) and Friedman & Visser (2014) to show that there are better candidates than mutual truth-definability for the role of sufficient condition for conceptual equivalence between the semantic notions associated with the theories. In the concluding part of the paper, I extend the techniques introduced in the first and show that there is a precise sense in which ramified truth (either disquotational or compositional) does not correspond to iterations of comprehension. (shrink)

We determine the modal logic of fixed-point models of truth and their axiomatizations by Solomon Feferman via Solovay-style completeness results. Given a fixed-point model $\mathcal {M}$, or an axiomatization S thereof, we find a modal logic M such that a modal sentence $\varphi $ is a theorem of M if and only if the sentence $\varphi ^*$ obtained by translating the modal operator with the truth predicate is true in $\mathcal {M}$ or a theorem of S under all such translations. (...) To this end, we introduce a novel version of possible worlds semantics featuring both classical and nonclassical worlds and establish the completeness of a family of noncongruent modal logics whose internal logic is nonclassical with respect to this semantics. (shrink)

It is no exaggeration to say that of the early 20th century German philosophers who claimed to establish a new ontology, former neo-Kantian turned realist Nicolai Hartmann is the only one to have actually followed through. "Ontology: Laying the Foundations" deals with "what is insofar as it is," and its four parts tackle traditional ontological assumptions and prejudices and traditional categories such as substance, thing, individual, whole, object, and phenomenon; a novel redefinition of existence and essence in terms of (...) the ontological factors Dasein and Sosein and their interrelations; an analysis of modes of "givenness" and the ontological embeddedness of cognition in affective transcendent acts; and a discussion of the status of ideal being, including mathematical being, phenomenological essences, logical laws, values, and the interconnections between the ideal and real spheres. Hartmann’s work offers rich resources for those interested in overcoming the human-centeredness of much 20th century philosophy. Hartmann’s work offers rich resources for those interested in overcoming the human-centeredness of much 20th century philosophy. (shrink)

When are two formal theories of broadly logical concepts, such as truth, equivalent? The paper investigates a case study, involving two well-known variants of Kripke–Feferman truth. The first, \, features a consistent but partial truth predicate. The second, \, an inconsistent but complete truth predicate. It is known that the two truth predicates are dual to each other. We show that this duality reveals a much stricter correspondence between the two theories: they are intertraslatable. Intertranslatability, under natural assumptions, coincides with (...) definitional equivalence, and is arguably the strictest notion of theoretical equivalence different from logical equivalence. The case of \ and \ raises a puzzle: the two theories can be proved to be strictly related, yet they appear to embody remarkably different conceptions of truth. We discuss the significance of the result for the broader debate on formal criteria of conceptual reducibility for theories of truth. (shrink)

Bd. 1. Abhandlungen zur systematischen Philosophie.--Bd. 2. Abhandlungen zur Philosophie-Geschichte.--Bd. 3. Vom Neukantianismus zur Ontologie.

This title from the De Gruyter Book Archive has been digitized in order to make it available for academic research. It was originally published under National Socialism and has to be viewed in this historical context. Learn more. >.

In the paper we survey the known connections between theories that extend a common base theory with typed truth axioms on the one hand and predicative set-existence assumptions on the other. How general can the mutual reductions between truth and comprehension be taken to be? In trying to address this question, we consider classical, positive truth and predicative comprehension as operations on theories.

Frontmatter -- Einleitung -- Erster Teil: Allgemeiner Begriff der Kategorien -- I. Abschnitt. Die Kategorien and das ideale Sein -- 1. Kapitel. Gleichsetzung von Prinzipien und Wesenheiten -- 2. Kapitel. Aufhebung der Gleichsetzung. Die Abgrenzung -- 3. Kapitel. Die Kategorien des idealen Seins -- 4. Kapitel. Inhaltlicher Überschuß der Realkategorien -- II. Abschnitt. Ontologische Fassungen und Fehlerquellen -- 5. Kapitel. Didaktischer Wert der Vorurteile -- 6. Kapitel. Der kategoriale Chorismos und die Homonymie -- 7. Kapitel. Kategoriale Grenzüberschreitung und Heterogeneität -- (...) 8. Kapitel. Kategorialer Teleologismus und Normativismus -- 9. Kapitel. Kategorialer Formalismus -- III. Abschnitt. Erkenntnistheoretische Fassungen und Fehlerquellen -- 10. Kapitel. Neue Aufgaben der Vernunftkritik -- 11. Kapitel. Kategorialer Apriorismus und Rationalismus -- 12. Kapitel. Vorurteile in den Identitätsthesen -- 13. Kapitel. Das Vorurteil der logisch-ontologischen Identität -- 14. Kapitel. Konsequenzen aus der Kritik der Identitätsthesen -- IV. Abschnitt. Fehlerquellen der philosophischen Systematik -- 15. Kapitel. Das Vorurteil des Einheitspostulats -- 16. Kapitel. Das Vorurteil des kategorialen Dualismus -- 17. Kapitel. Das Vorurteil des Harmoniepostulats -- Zweiter Teil: Die Lehre von den Fundamentalkategorien -- I. Abschnitt. Die Schichten des Realen und die Sphären -- 18. Kapitel. Die Erkenntnissphäre und ihre Stufen -- 19. Kapitel. Das Hineinspielen der idealen und logischen Sphäre -- 20. Kapitel. Die Lehre von den Schichten des Realen -- 21. Kapitel. Schichten des Realen und Schichten der Kategorien -- 22. Kapitel. Einordnung der sekundären Sphären in die Schichten des Realen -- II. Abschnitt. Die elementaren Gegensatzkategorien -- 23. Kapitel. Die Stellung der Seinsgegensätze. Geschichtliches -- 24. Kapitel. Die Tafel der Seinsgegensätze -- 25. Kapitel. Die innere Bezogenheit in der Gegensätzlichkeit -- 26. Kapitel. Gegenseitige Überordnung und Implikation der Gegensätze -- III. Abschnitt. Die Abwandlung der Seinsgegensätze in den Schichten -- 27. Kapitel. Kategorien minimaler Abwandlung -- 28. Kapitel. Relation und Substrat, Form und Materie -- 29. Kapitel. Einheit und Mannigfaltigkeit -- 30. Kapitel. Gegensatz und Dimension, Diskretion und Kontinuität -- 31. Kapitel. Determination und Dependenz -- 32. Kapitel. Einstimmigkeit und Widerstreit -- 33. Kapitel. Element und Gefüge -- 34. Kapitel. Inneres und Äußeres -- IV. Abschnitt. Die Kategorien der Qualität -- 35. Kapitel. Das Positive und das Negative -- 36. Kapitel. Identität und Verschiedenheit -- 37. Kapitel. Allgemeinheit und Individualität -- 38. Kapitel. Die qualitative Mannigfaltigkeit -- V. Abschnitt. Kategorien der Quantität -- 39. Kapitel. Eines und Vieles -- 40. Kapitel. Das Unendliche und das Continuum der reellen Zahlen -- 41. Kapitel. Die Rechnung und das Berechenbare -- Dritter Teil: Die kategorialen Gesetze -- I. Abschnitt. Gesetze der kategorialen Geltung -- 42. Kapitel. Das Problem der kategorialen Gesetzlichkeit -- 43. Kapitel. Das Geltungsgesetz des "Prinzips" -- 44. Kapitel. Die drei übrigen Geltungssätze -- II. Abschnitt. Gesetze der kategorialen Kohärenz -- 45. Kapitel. Das Gesetz der Verbundenheit -- 46. Kapitel. Die Gesetzlichkeit der interkategorialen Relation -- 47. Kapitel. Das Wesen der kategorialen Implikation -- 48. Kapitel. Zur Geschichte und Metaphysik der kategorialen Kohärenz -- 49. Kapitel. Hegels Idee der Dialektik -- ¿II. Abschnitt. Gesetze der kategorialen Schichtung -- 50. Kapitel. Das Höhenverhältnis der Kategorien -- 51. Kapitel. Das Gesetz der Wiederkehr -- 52. Kapitel. Zur Metaphysik der kategorialen Wiederkehr -- 53. Kapitel. Gesetz der Abwandlung und Gesetz des Novums -- 54. Kapitel. Das Gesetz der Schichtendistanz -- IV. Abschnitt. Gesetze der kategorialen Dependenz -- 55. Kapitel. Schichtung und Abhängigkeit -- 56. Kapitel. Das kategoriale Grundgesetz -- 57. Kapitel. Das Gesetz der Indifferenz und die lnversionstheorien -- 58. K. (shrink)