The notion of the riddle plays a pivotal role in Wittgenstein’s Tractatus . By examining the comparisons he draws between philosophical problems and riddles, this paper offers a reassessment of the aims and methods of the book. Solving an ordinary riddle does not consist in learning a new fact; what it requires is that we transform the way we use words. Similarly, Wittgenstein proposes to transform the way philosophers understand the nature of their problems. But since he holds that these (...) problems are ultimately unsolvable, rather than attempting to solve the riddles of philosophy, he aims to dissolve them. (shrink)

In theTractatus, Wittgenstein advocates two major notational innovations in logic. First, identity is to be expressed by identity of the sign only, not by a sign for identity. Secondly, only one logical operator, called “N” by Wittgenstein, should be employed in the construction of compound formulas. We show that, despite claims to the contrary in the literature, both of these proposals can be realized, severally and jointly, in expressively complete systems of first-order logic. Building on early work of Hintikka’s, we (...) identify three ways in which the first notational convention can be implemented, show that two of these are compatible with the text of theTractatus, and argue on systematic and historical grounds, adducing posthumous work of Ramsey’s, for one of these as Wittgenstein’s envisaged method. With respect to the second Tractarian proposal, we discuss how Wittgenstein distinguished between general and non-general propositions and argue that, claims to the contrary notwithstanding, an expressively adequate N-operator notation is implicit in theTractatuswhen taken in its intellectual environment. We finally introduce a variety of sound and complete tableau calculi for first-order logics formulated in a Wittgensteinian notation. The first of these is based on the contemporary notion of logical truth as truth in all structures. The others take into account the Tractarian notion of logical truth as truth in all structures over one fixed universe of objects. Here the appropriate tableau rules depend on whether this universe is infinite or finite in size, and in the latter case on its exact finite cardinality.As it is obviously easy to express how propositions can be constructed by means of this operation and how propositions are not to be constructed by means of it, this must be capable of exact expression.5.503. (shrink)

Wittgenstein’s Tractatus construes the nature of reasoning in a manner which sharply conflicts with the conventional wisdom that logic is normative, not descriptive of thought. For although we sometimes seem to reason incorrectly, Wittgenstein denies that we can make logical mistakes (5.473). My aim in this paper is to show that the Tractatus provides us with good reasons to rethink some of the central assumptions that are standardly made in thinking about the relation between logic and thought. In particular, the (...) rejection of logical mistakes is to be understood in connection with Wittgenstein’s non-psychological approach to the thinking subject (5.641). On Wittgenstein's view, inference, understanding, and meaning are holistically related; cases of defective reasoning are to be explained in terms of a defective grasp of meaning which manifests in an indeterminate use of signs. Invalid reasoning therefore does not count for Wittgenstein as a species of reasoning, but rather as the mere illusion of reasoning. The rejection of logical mistakes thus gives voice to a radical disjunctivist approach. (shrink)

The distinction between saying and showing in Tractatus Logico-Philosophicus is not self-refuting, unbelievable or nonsensical. It makes good sense given Wittgenstein's equation of saying with communicable information and showing with necessarily true thought. The key to understanding his thinking is his claim in the Preface that unassailable and definitive truths are expressed in the book, and the subsidiary assumption that asserting empty truths is nonsensical. His conception of pictures, propositions, logic, mathematics, mathematical physics, mysticism, the inexpressible and solipsism as showing (...) is of a piece with his conception of necessary/a priori truths as tautologies broadly understood. (shrink)

In the penultimate remark of the Tractatus Logico-Philosophicus Wittgenstein declares that anyone who understands him judges the book to be nonsense. The immediate reaction to this paradoxical statement is to reject the insights of the book that this assessment is based on; that is, to reject the book’s theories of logic and language. Commentators have tried to save the book’s fundamental philosophical ideas by blocking this immediate response. In this thesis I characterise and explore different attempts to do so. I (...) discuss attempts of Russell, Carnap, Max Black, Malcolm, Hacker’s Ineffability interpretation and Conant’s Therapeutic interpretation. I argue that the Therapeutic reading is the most promising attempt in its main ideas. Nonetheless, current versions of the Therapeutic readings do not seem successful. I borrow ideas from Grice’s pragmatic theory of conversation and Davidson’s account of metaphor to explain how the book is to be read therapeutically. I argue that the book is a long conversation between Wittgenstein and his audience which eventually turns out to be a pointless series of remarks. The book, however, works metaphorically in such a way that it affects its readers and helps them to divest themselves of the inclination to do philosophy. (shrink)

One of the central logical ideas in Wittgenstein’sTractatus logico-philosophicusis the elimination of the identity sign in favor of the so-called “exclusive interpretation” of names and quantifiers requiring different names to refer to different objects and (roughly) different variables to take different values. In this paper, we examine a recent development of these ideas in papers by Kai Wehmeier. We diagnose two main problems of Wehmeier’s account, the first concerning the treatment of individual constants, the second concerning so-called “pseudo-propositions” (Scheinsätze) of (...) classical logic such as$a=a$or$a=b \wedge b=c \rightarrow a=c$. We argue that overcoming these problems requires two fairly drastic departures from Wehmeier’s account: (1) Not every formula of classical first-order logic will be translatable into asingleformula of Wittgenstein’s exclusive notation. Instead, there will often be a multiplicity of possible translations, revealing the original “inclusive” formulas to beambiguous. (2) Certain formulas of first-order logic such as$a=a$will not be translatable into Wittgenstein’s notation at all, being thereby revealed as nonsensical pseudo-propositions which should be excluded from a “correct” conceptual notation. We provide translation procedures from inclusive quantifier-free logic into the exclusive notation that take these modifications into account and define a notion of logical equivalence suitable for assessing these translations. (shrink)

Book review of J. L. Zalabardo, Representation and Reality in Wittgenstein's Tractatus. Oxford: OUP 2015.

RESUMO O objetivo deste artigo é mostrar que as interpretações "tradicional" e "resoluta" não livraram o "Tractatus" da aparente autoderrota paradoxal. Argumento que essas leituras apresentam apenas uma nova roupagem ao paradoxo. A leitura "tradicional" de Hacker acaba atribuindo uma conspiração metafísica ao "Tractatus", o que é incompatível com os objetivos do livro. A leitura "resoluta" de Diamond e Conant atribui a Wittgenstein uma conspiração autoral, o que contradiz suas opiniões sobre autoria e método. Com base nas dificuldades encontradas em (...) ambos os lados do debate atual, concluo este artigo propondo vários requisitos que a correta interpretação do "Tractatus" deve preencher. (shrink)

The main question addressed by this article is this: How should one understand the role of the sentences of the Tractatus, given Wittgenstein’s statement that they are nonsensical? I begin with a presentation of three general principles of interpretation in order to avoid answering the question in an inappropriate way. I then move on to a short presentation and commentary on a selection of readings – namely, the ineffabilist, resolute and elucidatory ones – and elaborate the answers given by advocates (...) of these to the question explored here. I agree on many points with resolute and elucidatory readings: the Tractatus presents an austere conception of nonsense, and is not a book that seeks to present ontological or semantic theories. I point out, however, that these readings cannot fully explain the nature of Tractarian elucidations. Then I discuss those parts of the Tractatus which refer to the sentences of the book itself. The main proposal of my own approach is this: Tractarian elucidations should be construed as rules of translation, in that they show how to substitute certain expressions for others. They enable us to construct a notation in which everything that is expressible in ordinary language can be said perspicuously. (shrink)