The book provides a historical and systematic exposition of the semantic theory of truth formulated by Alfred Tarski in the 1930s. This theory became famous very soon and inspired logicians and philosophers. It has two different, but interconnected aspects: formal-logical and philosophical. The book deals with both, but it is intended mostly as a philosophical monograph. It explains Tarski’s motivation and presents discussions about his ideas as well as points out various applications of the semantic theory of truth to philosophical (...) problems. (shrink)

The short answer to this question is a firm and unambiguous “yes and no”. The long answer will take the whole talk. Indeed, it could easily take an entire book. It is therefore unavoidable to take recourse here and there to simplifying shortcuts and polemical exaggerations, in order to get the message clear.

In his paraphasis of Aristotle’s Metaphysics, Avicenna seems to adopt a first principle distintc form the one adopted by the Greek philosopher for this science. In fact, some interpreters consider him as prefering the principle of third excluded instead of the principle of non contradiction. Since I desagree with this thesis, I propose to analyse here Avicenna’s formulation of the first principle. In order to do that, I propose, first, to clarify the meaning of the first principle by looking to (...) one of the most important modern critics: Jan Lukasiewicz. To put it briefly, the question I will try to answer is: how Avicenna and Aristotle justify the nature of the logical relations. The article finishes with make some general remarks on Avicenna’s defense of the first principle. (shrink)

The aim of this paper is to show that it is the explicativecharacter of Tarski's semantic definition of truth given in his study of 1933 that allows forconsideration of a philosophical background of this definition in the proper sense. Given the explicativecharacter of this definition it is argued that the philosophical tradition that should be taken intoaccount with regard to this philosophical background is the tradition of the Lvov-Warsaw Schoolin its connections with the School of Brentano. As an example of (...) the explanatory power ofconsidering this tradition as far as Tarski's philosophical choices are concerned I use here thenotion of sentence-inscription, i.e., the notion of that entity of which truth is predicated inthe definition in question. One of the consequences of these statements is that philosophicaldiscussions concerning the semantic definition of truth can be regarded from two points ofview. On the one hand, they may take the perspective of its explicational function, i.e., theperspective of its philosophical background. On the other hand, they might consider the philosophicalconsequences of the definition with respect to the goal of the explication, i.e., they may considerits philosophical content independently of its historical background. (shrink)

It is often thought that instances of the T-schema such as snow is white is true if and only if snow is white state correspondences between sentences andthe world, and that therefore such sentences play a crucial role in correspondence theories oftruth. I argue that this assumption trivializes the correspondence theory: even a disquotationaltheory of truth would be a correspondence theory on this conception. This discussionallows one to get clearer about what a correspondence theory does claim, and toward the end (...) of thepaper I discuss what a true correspondence theory of truth would involve. (shrink)

In a paper entitled A Semantical Version of the Problem of Transcendental Idealism, Kazimierz Ajdukiewicz gives a very impressive analysis of transcendental idealism. He approaches the matter using the tools of formal semantics developed by Alfred Tarski and draws a rather surprising conclusion. According to Ajdukiewicz, the idealist position, claiming that the world around us is ontologically dependent on our cognitive activity can be shown to be implausible on purely logical grounds. It is worth taking a closer look at this (...) insightful argument, since Ajdukiewicz’s analysis, if sound, has a relevance reaching far beyond purely historical questions concerning the right interpretation and proper assessment of past idealist doctrines. These days various species of idealism are thriving under such labels as ‘anti realism’ or ‘pragmatism’. Ajdukiewicz’s venerable paper goes to the very core of many contemporary metaphysical discussions. (shrink)

Maria Kokoszyńska-Lutmanowa was one of the most outstanding female representatives of the Lvov-Warsaw School. After achieving her PhD in philosophy under Kazimierz Twardowski’s supervision, she was Kazimierz Ajdukiewicz’s assistant. She was also influenced by Alfred Tarski whose results in semantics she analyzed and popularized. After World War II, she got the chair of logic in University of Wrocław and she organized studies in logic in this academic center. In the 1930s, Kokoszyńska kept in contact with members of the Vienna Circle (...) and became a kind of connecting factor between Polish logicians and the Viennese group. In Poland, she presented the views of members of the Vienna Circle. In Vienna, she emphasized the results of her Polish colleagues. In the present paper, some of Kokoszyńska’s results connected with the matters discussed in the Vienna Circle are presented, namely with the problem of metaphysics, the status of logic and the idea of unity of science. (shrink)

In the paper, Jan Łukasiewicz’s program of the logicization of philosophy is presented and discussed. Łukasiewicz, known mostly for his invention of trivalent logic as well as his achievements in propositional calculus and metalogic, had always been concerned with the methodological condition of philosophy. He finally found “the measure of exactness” in mathematical logic. According to him, only the use of logical tools may provide philosophical investigations with an appropriate level of exactness. He expressed his views most firmly and directly (...) in the paper, “A call for the method of Philosophy”. Łukasiewicz proposed giving philosophical theories the form of axiomatic systems by indicating the primitive terms of their language, selecting suitable axioms, and explicitly determining the applied rules of inference. All the theses of these systems should be consequences of the accepted axioms and confronted with the data of experience and the results of science. Łukasiewicz’s program is presented together with its inspirations and prospects. (shrink)

I defend the correspondence theory of truth, according to which a statement’s truth consists in a relation of correspondence with extralinguistic fact. There are well-known objections to this view, which I consider and rebut, and also important rival accounts, principal among which are so-called deflationist theories and epistemic theories. Epistemic theories relate the concept of truth to our state of knowledge, but fail, I argue, to respect the crucial distinction between a criterion of truth and the meaning of truth: the (...) view that one cannot do semantics, or metaphysics, without addressing epistemic issues is rejected by this work. Against epistemic theories, I illustrate how truth is independent of epistemic considerations. Deflationism is the more popular of the rival accounts and has gained considerable momentum over the past two decades. It is therefore dealt with in greater detail by this work. Deflationist theories exploit the paradigmatic ‘“Snow is white” is true iff snow is white’ biconditional to argue for an insubstantialist account, according to which truth is conservative with respect to non-semantical facts. On this view, truth’s raison d’être is merely to perform the useful expressive function of generalising over possibly infinite sets of assertions. Against deflationist theories, I claim that the work done by Jeffrey Ketland and Stewart Shapiro conclusively demonstrates how truth is informationally additive over non-semantic facts, while deflationism itself is also an excessively impoverishing theory, inadequate to the tasks it purports to accomplish. This work also defends the thesis that Alfred Tarski’s well-known theory of truth is an authentic correspondence theory. To say this is to say that the clauses of a Tarskian truth-definition can be interpreted in terms of a relation of correspondence that holds between true sentences and the states of affairs they describe. I provide a precise account of what the correspondence in question consists in, claiming that true sentences are homomorphic images of facts, i.e. a true sentence represents, in a form-preserving manner, the truth-making facts in it. This gives precise expression to Wittgenstein’s thesis that true sentences picture the world. (shrink)

Why have Polish philosophers fared so badly as concerns their admission into the pantheon of Continental Philosophers? Why, for example, should Heidegger and Derrida be included in this pantheon, but not Ingarden or Tarski? Why, to put the question from another side, should there be so close an association in Poland between philosophy and logic, and between philosophy and science? We distinguish a series of answers to this question, which are dealt with under the following headings: (a) the role of (...) socialism; (b) the disciplinary association between philosophy and mathematics; (c) the influence of Austrian philosophy in general and of Brentanian philosophy in particular; (d) the serendipitous role of Twardowski; (e) the role of Catholicism. The conclusion of the paper is that there is no such thing as 'Polish philosophy' because philosophy in Poland is philosophy per se; it is part and parcel of the mainstream of world philosophy simply because, in contrast to French or German philosophy, it meets international standards of training, rigour, professionalism and specialization. (shrink)