The paper offers an interpretation of thesis 6.01. The treatment touches upon variables, identity, elementary propositions, internal relations. Klammerausdrücke, and operations. Wittenstein's notations are found not to cover the particular form of definition by induction that is used at 6 and 6.01. It is concluded that Wittgenstein's ability to design of a formal system of logic does not match his outstanding logico-philosophical insight.

It is a little understood fact that the system of formal logic presented in Wittgenstein?s Tractatusprovides the basis for an alternative general semantics for a predicate calculus that is consistent and coherent, essentially independent of the metaphysics of logical atomism, and philosophically illuminating in its own right. The purpose of this paper is threefold: to describe the general characteristics of a Tractarian-style semantics, to defend the Tractatus system against the charge of expressive incompleteness as levelled by Robert Fogelin, and to (...) give a semantics for a formal language that is the Tractarian equivalent of a first-order predicate calculus. Of note in regard to the latter is the fact that a Tractatusstyle truth-definition makes no appeal to the technical trick of defining truth in terms of the satisfaction of predicates by infinite sequences of objects, yet is materially equivalent to the usual Tarski-style truth-definitions. (shrink)

We investigate a rst-order predicate logic based on Wittgenstein's suggestion to express identity of object by identity of sign, and difference of objects by difference of signs. Hintikka has shown that predicate logic can indeed be set up in such a way; we show that it can be done nicely. More specically, we provide a perspicuous cut-free sequent calculus, as well as a Hilbert-type calculus, for Wittgensteinian predicate logic and prove soundness and completeness theorems.

No serious philosopher or student of philosophy can afford to neglect Wittgenstein's work. Professor Fogelin provides an authoritative critical evaluation of both the _Tractatus Logico-Philosophicus_ and _Philosophical Investigations_, enabling the reader to come to grips with these difficult yet key works. Fogelin explains Wittgenstein's attempt in the _Tractatus_ to combine a picture theory of propositional structure, and also explores Wittgenstein's own criticisms of the Tractarian synthesis. He gives particular attention to topics in the philosophy of language, logic, psychology and the (...) foundations of mathematics, examining Wittgenstein's work on these fields and arguing that Wittgenstein's criticisms in these areas form the basis for a radically new standpoint in philosophy. (shrink)

This book offers a lucid and highly readable account of Wittgenstein's philosophy, framed against the background of his extraordinary life and character. Woven together with a biographical narrative, the chapters explain the key ideas of Wittgenstein's work, from his first book, the Tractatus Logico-Philosophicus, to his mature masterpiece, the Philosophical Investigations.

We investigate a variant of the variable convention proposed at Tractatus 5.53ff for the purpose of eliminating the identity sign from logical notation. The variant in question is what Hintikka has called the strongly exclusive interpretation of the variables, and turns out to be what Ramsey initially (and erroneously) took to be Wittgenstein's intended method. We provide a tableau calculus for this identity-free logic, together with soundness and completeness proofs, as well as a proof of mutual interpretability with first-order logic (...) with identity. (shrink)

The paper offers an interpretation of thesis 6.01. The treatment touches upon variables, identity, elementary propositions, internal relations. Klammerausdrücke, and operations. Wittenstein's notations are found not to cover the particular form of definition by induction that is used at 6 and 6.01. It is concluded that Wittgenstein's ability to design of a formal system of logic does not match his outstanding logico-philosophical insight.

Wittgensteinian predicate logic (W-logic) is characterized by the requirement that the objects mentioned within the scope of a quantifier be excluded from the range of the associated bound variable. I present a sound and complete tableaux calculus for this logic and discuss issues of translatability between Wittgensteinian and standard predicate logic in languages with and without individual constants. A metalinguistic co-denotation predicate, akin to Frege’s triple bar of the Begriffsschrift, is introduced and used to bestow the full expressive power of (...) first-order logic with identity on W-logic in the presence of constants. (shrink)

Tractatus Logico-Philosophicus by Ludwig Wittgenstein: three parallel tree-structured editions. (1) Tree-structured arrangement of the German text, edited by David G. Stern, Joachim Schulte and Katia Saporiti. (2) Tree-structured arrangement of the English translation by Ogden and Ramsey, edited by David G. Stern. (3) Tree-structured arrangement of the English translation by Pears and McGuinness, edited by David G. Stern.

Analysis of quantifiers in Wittgenstein's Tractatus. A critical survey In the Tractatus Logico-Philosophicus, Wittgenstein distinguishes between what can and cannot be said in any language by the general form of propositions. I explain Wittgenstein's method and discuss Robert J. Fogelin's criticism of what he takes to be the incompleteness of Wittgenstein's general form of propositions in his exposition of the 'Naive Constructivism of the Tractatus.' I argue that Fogelin's objection is mistaken, and that, contrary to Fogelin's claim, Wittgenstein's method when (...) properly applied produces all of the well-formed formulas with mixed multiple quantification that Fogelin maintains it cannot provide. I conclude by offering a critical comparison of similar solutions proposed, among others, by P.T. Geach, Scott Soames, and Matthias Varga von Kibéd. (shrink)

It is a little understood fact that the system of formal logic presented in Wittgenstein’s Tractatusprovides the basis for an alternative general semantics for a predicate calculus that is consistent and coherent, essentially independent of the metaphysics of logical atomism, and philosophically illuminating in its own right. The purpose of this paper is threefold: to describe the general characteristics of a Tractarian-style semantics, to defend the Tractatus system against the charge of expressive incompleteness as levelled by Robert Fogelin, and to (...) give a semantics for a formal language that is the Tractarian equivalent of a first-order predicate calculus. Of note in regard to the latter is the fact that a Tractatusstyle truth-definition makes no appeal to the technical trick of defining truth in terms of the satisfaction of predicates by infinite sequences of objects, yet is materially equivalent to the usual Tarski-style truth-definitions. (shrink)

The paper offers an interpretation of thesis 6.01. The treatment touches upon variables, identity, elementary propositions, internal relations. Klammerausdrücke, and operations. Wittenstein's notations are found not to cover the particular form of definition by induction that is used at 6 and 6.01. It is concluded that Wittgenstein's ability to design of a formal system of logic does not match his outstanding logico-philosophical insight.

Wittgenstein's "Tractatus" claims the possibility to represent quantificational logic by means of a single basic operation. Fogelin regards the "Tractatus" system as seriously flawed and thus not suited for this aim, while Geach and Soames propose extensions and corrections of the Tractarian notational system. If the unusual Tractarian view -- every variable can be conceived as a propositional variable -- is taken full account of, we find out, that the "Tractatus" system is well suited to deal even with the problematic (...) cases of mixed quantifiers with many-place predicates. By expanding the view of variables as certain two-dimensional lists of propositions we find adequate representations of formulas like fxy in the logic of the "Tractatus". Surprisingly we don't need anything which corresponds to formulas with two or more free variables like fxy, and still get the full power of ordinary quantificational logic. (shrink)

The purpose of this paper is threefold. First, I visit the Fogelin–Geach-dispute, criticizeMiller''s interpretation of the Geachian notationN(x:N(fx)) and conclude that Fogelin''s argumentagainst the expressive completeness of the Tractariansystem of logic is unacceptable and that the adoptionof the Geachian notation N(x:fx) would not violate TLP5.32. Second, I prove that a system of quantificationtheory with finite domains and with N as the solefundamental operation is expressively complete. Lastly, I argue that the Tractarian system is apredicate-eliminated many-sorted theory (withoutidentity) with finite domains (...) and with N as the solefundamental operation, and thus is expressivelycomplete. (shrink)

The power of Wittgenstein's N operator described in the Tractatus is that every proposition which can be expressed in the Russellian variant of the predicate calculus familiar to him has an equivalent proposition in an extended variant of his N operator notation. This remains true if the bound variables are understood in the usual inclusive sense or in Wittgenstein's restrictive exclusive sense. The problematic limit of Wittgenstein's N operator comes from his claim that symbols alone reveal the logical status of (...) propositions. This would require knowledge of the size of the Tractarian domain of unchangeable, simple objects, and this, Wittgenstein maintained, cannot be known. (shrink)