In the discussion at hand I have attempted to pave the way for such a treatment of the principle of contradiction. In a number of respects it seems to me worthwhile to relate my critical exposition to Aristotle's train of thought. Indeed, every critique must be raised against something substantial, otherwise it generally becomes the critic's leisurely game with his own cerebral phantasies. Now Aristotle's intuitions regarding the principle of contradiction are, for the most part and clear down to the (...) present day, the usual and traditional ones; and arguments for and against the principle can be found together in the Stagirite in greater completeness than in any one modern textbook of logic. My investigation will proceed with the Aristotelian text at hand and with regard to the results of symbolic logic. The most important results shall be sketched very briefly in the following. (shrink)

O logice Stoików pisali Prantl, Zeller, Brochard. Żaden z nich nie zrozumiał tej logiki, bo żaden z nich nie miał dostatecznego wykształcenia logicznego. Co prawda, nie można im nawet robić z tego zarzutu, bo skądże się mieli logiki nauczyć? Sądy ich o logice stoickiej nie mają żadnej wartości. Dopiero dziś wiemy, dzięki logice matematycznej, że logika Stoików jest systemem całkowicie różnym od syllogistyki Arystotelesa. Logika stoicka bowiem jest odpowiednikiem dzisiejszej "teorji dedu...

La logique des stoïciens a été déjà étudiée par Prantl, Zeller et Brochard. Aucun d’entre eux ne l’a comprise, car aucun n’avait de formation suffisante en logique. Il est vrai que cela ne peut même pas leur être reproché, car, après tout, où pouvaient-ils l’apprendre? Leurs jugements sur la logique stoïcienne n’ont aucune valeur. Ce n’est qu’aujourd’hui que nous savons, grâce à la logique mathématique, que la logique des stoïciens est un système entièrement différent de la syllogistique d’A...

Les Premiers Analytiques sont pour Lukasiewicz un livre de logique et non de philosophie. Il dit meme que cet ouvrage de pure logique ne contient aucune contamination philosophique. Mais cela ne veut pas dire qu'il n'a rien a apprendre aux philosophes et aux metaphysiciens sur les formalismes et sur les modalites. Comme le dit Lukasiewicz: Il reste encore des philosophes en activite auxquels il ne serait peut-etre pas impossible de suggerer qu'ils devraient acquerir une bonne connaissance de la logique dite (...) mathematique avant de traiter de la logique et de son histoire; ils eviteraient ainsi de perdre leur temps, leurs lecteurs de meme, ce qui n'est peut-etre pas denue d'importance pratique. Lukasiewicz est l'un des philosophes de l'Ecole de Lvov-Varsovie, courant philosophique majeur du XXe siecle. Son premier livre portait sur le principe de contradiction chez Aristote. Il en montrait l'importance, mais aussi la fragilite logique. Son dernier livre, consacre a la syllogistique, une partie de la logique, porte de nouveau sur Aristote. Pour peu qu'elle n'ignore pas Frege, les matrices logiques de Peirce, les Principia Mathematica de Russell et Whitehead ainsi que les apports considerables des logiciens polonais, comme Lesniewski, Sfupecki, et Lukasiewicz lui-meme, l'histoire de la logique, et en l'occurrence l'etude des Premiers Analytiques, constitue une voie d'acces privilegiee pour comprendre ce que sont les formalismes. (shrink)

Jan Salamucha was born on the 10th of June 1903 in Warsaw and murdered on the 11th of August 1944 in Warsaw during the Warsaw Uprising very early on in his scholarly career. He is the most original representative of the branch of the Lvov-Warsaw School known as the Cracow Circle. The Circle was a grouping of scholars who were interested in reconstructing scholasticism and Christian philosophy in general by means of mathematical logic. As Jan Lukasiewicz’s successor in the area (...) of logic and Konstanty Michalski’s student in the area of the history of medieval thought, Salamucha had an excellent preparation for this task. His main achievements include a masterful logical analysis of the proof _ex motu _for the existence of God, a modern interpretation of analogical notions and a comprehensive approach to the problem of essence. He also contributed several historical studies: he examined Aristotle’s theory of deduction, he reconstructed William Ockham’s propositional logic and established the authenticity of his treatise on _insolubilia,_ and he identified the historical sources of the antinomies in Antiquity and the Middle Ages. He did not shy away from popularizing philosophy, and in that work he was able to elucidate rather than oversimplify the complexities of philosophy. (shrink)

One can often encounter an opinion that Polish scientific philosophy deserves to be much better known than actually is. This book is thought as a response to such a claim. The papers collected in this volume are divided into two parts: Background and Influence and History and Systematics. However, there is no sharp borderline between themes which are touched in both parts. Generally speaking, all papers of the first part relate the Lvov-Warsaw School to some philosophical movements external to it (...) whereas the papers collected in the second one focus on internal issues connected with the school . Since the Polish school of mathematical logic is much better known than the Polish analytic philosophy we decided to omit here any treatment of the former. Thus, this collection centers on purely philosophical matters. We projected this volume not as an exhaustive panorama of Polish analytic philosophy but rather as a series of essays on particular persons or topic. As a result one can find here papers on Twardowski. Ajdukiewicz, Kotarbinski, Tarski and Lukasiewicz as well as on ethics on science, nominalism, and the methodology of psychology. We hope that this book will contribute to a better knowledge and evaluation of Polish achievements in analytic philosophy. We would like to express our gratitude to Professor Leszek Nowak, the editor-in-chief of Poznan Studies in the Philosophy of the Sciences and the Humanities, who initiated the idea of the collection and helped in its preparation. (shrink)

Ancien etudiant de Brentano et de Zimmerman, Kazimierz Twardowski, apres son election a la chaire de philosophie a Lvov en 1895, crea autour de lui un cercle d'etudiants et de collaborateurs exceptionnel, connu aujourd'hui sous le nom d'Ecole de Lvov-Varsovie. A mi-chemin entre Vienne et Cambridge, c'est a Lvov, et puis partiellement a Varsovie, que Jan Lukasiewicz, Stanislaw Lesniewski, Alfred Tarski, Kazimierz Ajdukiewicz, Tadeusz Kotarbinski et bien d'autres encore, repenserent dans un esprit d'analyse les questions fondamentales de la philosophie du (...) langage, de la logique, de la philosophie des sciences et des mathematiques. Plus qu'une simple traduction, ce livre est une version revisee de la monographie desormais classique que Jan Wolenski, connu pour ses travaux non seulement en histoire de la philosophie analytique, mais aussi en epistemologie et en theorie de la verite, a consacree a l'Ecole de Lvov-Varsovie. (shrink)

In this note, we show that the first-order logic IKω is sound with regard to the models obtained from continuum-valued Łukasiewicz-models for first-order languages by treating the quantifiers as infinitary strong disjunction/conjunction rather than infinitary weak disjunction/conjunction. Moreover, we show that these models cannot be used to provide a new consistency proof for the theory of truth IKTω obtained by expanding IKω with transparent truth, because the models are inconsistent with transparent truth. Finally, we show that whether or not (...) this inconsistency can be reproduced in the sequent calculus for IKTω depends on how vacuous quantification is treated. (shrink)

Poland has played an enormous role in the development of mathematical logic. Leading Polish logicians, like Lesniewski, Lukasiewicz and Tarski, produced several works related to philosophical logic, a field covering different topics relevant to philosophical foundations of logic itself, as well as various individual sciences. This collection presents contemporary Polish work in philosophical logic which in many respects continue the Polish way of doing philosophical logic. This book will be of interest to logicians, mathematicians, philosophers, and linguists.

Les Premiers Analytiques sont pour Lukasiewicz un livre de logique et non de philosophie. Il dit meme que cet ouvrage de pure logique ne contient aucune contamination philosophique. Mais cela ne veut pas dire qu'il n'a rien a apprendre aux philosophes et aux metaphysiciens sur les formalismes et sur les modalites. Comme le dit Lukasiewicz: Il reste encore des philosophes en activite auxquels il ne serait peut-etre pas impossible de suggerer qu'ils devraient acquerir une bonne connaissance de la logique dite (...) mathematique avant de traiter de la logique et de son histoire; ils eviteraient ainsi de perdre leur temps, leurs lecteurs de meme, ce qui n'est peut-etre pas denue d'importance pratique. Lukasiewicz est l'un des philosophes de l'Ecole de Lvov-Varsovie, courant philosophique majeur du XXe siecle. Son premier livre portait sur le principe de contradiction chez Aristote. Il en montrait l'importance, mais aussi la fragilite logique. Son dernier livre, consacre a la syllogistique, une partie de la logique, porte de nouveau sur Aristote. Pour peu qu'elle n'ignore pas Frege, les matrices logiques de Peirce, les Principia Mathematica de Russell et Whitehead ainsi que les apports considerables des logiciens polonais, comme Lesniewski, Sfupecki, et Lukasiewicz lui-meme, l'histoire de la logique, et en l'occurrence l'etude des Premiers Analytiques, constitue une voie d'acces privilegiee pour comprendre ce que sont les formalismes. (shrink)

THE great Polish logician Jan Lukasiewicz died on February 13, 1956 in Dublin, where, thanks to the hospitality of the Irish Government and the Royal Irish Academy, he had spent the last ten years of his life as a distinguished professor of the Academy. Thanks to the help he received in Dublin, he was able not only to reconstruct and prepare his papers for publication, but was also able to carry on new research in the field of symbolic logic, obtaining (...) several new and important results. Thus, due to the odd and dreadful historical circumstances of our times, the name of this Polish scientist is connected not only with his native country, but also with Ireland. (shrink)

This volume offers to the English-speaking world a collection of important works by the eminent twentieth century logician, Jan Lukasiewicz, many of which are here translated into English for the first time. This edition differs significantly from the Polish edition which appeared in 1961—containing ten logic papers not appearing there and omitting articles primarily of interest to the Polish reader. In addition to writing in Polish, Lukasiewicz also published works in French, English, and notably in German, and sometimes translated his (...) own works from one language to another. One of the most valuable works on the history of logic is Lukasiewicz’ paper, "On the History of the Logic of Propositions". Lukasiewicz points out the difference between the two basic areas of formal logic, the logic of propositions and the logic of terms, undifferentiated before the development of modern mathematical logic. The understanding of this distinction leads Lukasiewicz to trace the history of propositional logic back to its original development by the Stoics, its further development by the medieval Scholastics, and its axiomatization by Gottlob Frege. The status of mathematical logic is discussed in various works. The most basic system is propositional logic, upon which depend the other logical disciplines and also mathematics. Mathematical logic, also called logistic, is independent of philosophy and espouses no philosophical viewpoint. Early in his career, Lukasiewicz refers to mathematical logic as the logic of algebra and uses mathematical symbolism to represent logical propositions. Later he introduces what we now call "Polish notation," in particular, "Cpq" for "if p, then q" and "Np" for "it is not the case that p" for the primitive functions, eliminating the need for punctuation. He adopts the symbols Π and Σ for quantification from Charles S. Peirce, and also brings to light the almost unknown fact that it was Peirce who invented the matrix method in 1885. The paper, "Investigations into the Sentential Calculus", written by Lukasiewicz and Tarski embodies the results of a decade of research on the sentential calculus initiated by Lukasiewicz at the University of Warsaw systematically compiling the contributions of five logicians: Lindenbaum, Sobocinski, Wajsberg, Tarski, and Lukasiewicz. The approach is metalogical and depends heavily upon set theoretic concepts; it covers both the matrix and axiomatic methods. One of the problems that preoccupied Lukasiewicz was that of determinism, which led to his development of three-valued logic. A proposition such as "I shall be in Warsaw at noon on 21 December of next year" is neither true nor false; a third truth value is needed, one which Lukasiewicz calls "the possible." Another area to which Lukasiewicz contributed is modal logic, proving that modal logic cannot be two-valued. Lukasiewicz’ analysis and axiomatization of Aristotle’s syllogistic is not included in the present volume since an English edition by Lukasiewicz on this topic is available. We have here briefly touched upon a few of Lukasiewicz’ numerous achievements in logic; the best means of appreciating them is to read his works.—T. G. N. (shrink)