Introduction. The School: Its Genesis, Development and Significance

The Introduction outlines, in a concise way, the history of the Lvov-Warsaw School – a most unique Polish school of worldwide renown, which pioneered trends combining philosophy, logic, mathematics and language. The author accepts that the beginnings of the School fall on the year 1895, when its founder Kazimierz Twardowski, a disciple of Franz Brentano, came to Lvov on his mission to organize a scientific circle. Soon, among the characteristic features of the School was its serious approach towards philosophical studies and teaching of philosophy, dealing with philosophy and propagation of it as an intellectual and moral mission, passion for clarity and precision, as well as exchange of thoughts, and cooperation with representatives of other disciplines.The genesis is followed by a chronological presentation of the development of the School in the successive years. The author mentions all the key representatives of the School (among others, Ajdukiewicz, Lesniewski, Łukasiewicz,Tarski), accompanying the names with short descriptions of their achievements. The development of the School after Poland’s regaining independence in 1918 meant part of the members moving from Lvov to Warsaw, thus providing the other segment to the name – Warsaw School of Logic. The author dwells longer on the activity of the School during the Interwar period – the time of its greatest prosperity, which ended along with the outbreak of World War 2. Attempts made after the War to recreate the spirit of the School are also outlined and the names of followers are listed accordingly. The presentation ends with some concluding remarks on the contribution of the School to contemporary developments in the fields of philosophy, mathematical logic or computer science in Poland

Некоторые парадоксы, подобные «лжецу»

This paper formulates some liar-like paradoxes. The basic idea is that self-referentiality, classical logic and T-equivalences are sources of related paradoxes. This background is motivated by Leśniewski’s-Tarski’s analysis of the classical Liar-antinomy. In particular, paradoxes for pedicates “is meaningless” and “is not rational” are stated.В этой статье представлены некоторые подобные «Лжецу» парадоксы. Основная идея состоит в том, что их источником являются самореферентность, классический характер логики и эквивалентности, связанные с предикатом истинности Т. В основе такого понимания лежит анализ классической антиномии «Лжец» у Лесневского и Тарского. В частности, представлены парадоксы, возникающие в связи с предикатами «быть лишённым значения» и «не быть рациональным»

Некоторые парадоксы, подобные «лжецу»

This paper formulates some liar-like paradoxes. The basic idea is that self-referentiality, classical logic and T-equivalences are sources of related paradoxes. This background is motivated by Leśniewski’s-Tarski’s analysis of the classical Liar-antinomy. In particular, paradoxes for pedicates “is meaningless” and “is not rational” are stated.В этой статье представлены некоторые подобные «Лжецу» парадоксы. Основная идея состоит в том, что их источником являются самореферентность, классический характер логики и эквивалентности, связанные с предикатом истинности Т. В основе такого понимания лежит анализ классической антиномии «Лжец» у Лесневского и Тарского. В частности, представлены парадоксы, возникающие в связи с предикатами «быть лишённым значения» и «не быть рациональным»

Rejection in Łukasiewicz's and Słupecki's Sense

The idea of rejection originated by Aristotle. The notion of rejection was introduced into formal logic by Łukasiewicz [20]. He applied it to complete syntactic characterization of deductive systems using an axiomatic method of rejection of propositions [22, 23]. The paper gives not only genesis, but also development and generalization of the notion of rejection. It also emphasizes the methodological approach to biaspectual axiomatic method of characterization of deductive systems as acceptance (asserted) systems and rejection (refutation) systems, introduced by Łukasiewicz and developed by his student Słupecki, the pioneers of the method, which becomes relevant in modern approaches to logic

Overcoming Psychologism. Twardowski on Actions and Products

This paper is about the topic of psychologism in the work of Kazimierz Twardowski and my aim is to revisit this important issue in light of recent publications from, and on Twardowski’s works. I will first examine the genesis of psychologism in the young Twardowski’s work; secondly, I will examine Twardowski’s picture theory of meaning and Husserl’s criticism in Logical Investigations; the third part is about Twardowski’s recognition and criticism of his psychologism in his lectures on the psychology of thinking; the fourth and fifth parts provide an overview of Twardowski’s paper “Actions and Products” while the sixth part addresses the psychologism issue in the last part of this paper through the delineation of psychology and the humanities. I shall conclude this study with a brief assessment of Twardowski’s solution to psychologism