There are two main ways in which the notion of mereological fusion is usually defined in the current literature in mereology which have been labelled ‘Leśniewski fusion’ and ‘Goodman fusion’. It is well-known that, with Minimal Mereology as the background theory, every Leśniewski fusion also qualifies as a Goodman fusion. However, the converse does not hold unless stronger mereological principles are assumed. In this paper I will discuss how the gap between the two (...) notions can be filled, focussing in particular on two specific sets of principles that appear to be of particular philosophical interest. The first way to make the two notions equivalent can be used to shed some interesting light on the kind of intuition both notions seem to articulate. The second shows the importance of a little-known mereological principle which I will call ‘Mild Supplementation’. As I will show, the mereology obtained by adding Mild Supplementation to Minimal Mereology occupies an interesting position in the landscape of theories that are stronger than Minimal Mereology but weaker than what Achille Varzi and Roberto Casati have labelled ‘Extensional Mereology’. (shrink)

The paper aims to reconstruct Heidegger’s historical-intentional assumptions in his ontological interpretation of Kant’s Critique of Pure Reason. The paper presents young Heidegger’s project of the “metaphysical-teleological interpretation of consciousness.” The project indicates the direction of his further ontological interpretation of transcendentalism: Heidegger stands up to the traditional, well known neo-Kantian interpretation of the Critique, and offers a new conception of ontological knowledge and cognition. According to this conception, cognition is grounded in transcendental imagination where a threefold synthesis takes place. (...) Heidegger’s original temporal interpretation of transcendental schematism is also recalled to stress the significance of his new ontological approach to Kant’s theoretical philosophy. (shrink)

The point of departure in the paper is the problem of Heidegger’s interpretation of Nietzsche’s thought in the light of the problematic term “Perspektivismus”. The author explicates the methodological position taken by Heidegger in his interpretation to give an answer to the question of epistemical, ontological or methodological domain of perspectivism.

1. First, a short anecdote. In the mid-1980s, Professor Jerzy Pogonowski gave a series of lectures entitled The Lvov-Warsaw School at the Institute of Philosophy at the Adam Mickiewicz University i...

In this paper† we will treat mereology as a theory of some structures that are not axiomatizable in an elementary langauge and we will use a variable rangingover the power set of the universe of the structure). A mereological structure is an ordered pair M = hM,⊑i, where M is a non-empty set and ⊑is a binary relation in M, i.e., ⊑ is a subset of M × M. The relation ⊑ isa relation of being a mereological part . We (...) formulate an axiomatization of mereological structures, different from Tarski’s axiomatization aspresented in [10] . We prove that these axiomatizations are equivalent . Of course, these axiomatizations are definitionally equivalent to thevery first axiomatization of mereology from [5], where the relation of being aproper part ⊏ is a primitive one.Moreover, we will show that Simons’ “Classical Extensional Mereology”from [9] is essentially weaker than Leśniewski’s mereology. (shrink)

Mereology is the theory of the relation “being a part of”. The first exact formulation of mereology is due to the Polish logician Stanisław Leśniewski. But Leśniewski’s mereology is not first-order axiomatizable, for it requires every subset of the domain to have a fusion. In recent literature, a first-order theory named General Extensional Mereology can be thought of as a first-order approximation of Leśniewski’s theory, in the sense that GEM guarantees that every definable subset of the (...) domain has a fusion, and this has been achieved by positing an axiom schema which in effect defines infinitely many axioms. Intuitively, in order to range over every definable subset, such an axiom schema seems unavoidable. But this paper will show that GEM is finitely axiomatizable and that all we need are just finitely many instances of the said axiom schema. (shrink)

Leśniewski’s systems deviate greatly from standard logic in some basic features. The deviant aspects are rather well known, and often cited among the reasons why Leśniewski’s work enjoys little recognition. This paper is an attempt to explain why those aspects should be there at all. Leśniewski built his systems inspired by a dream close to Leibniz’s characteristica universalis: a perfect system of deductive theories encoding our knowledge of the world, based on a perfect language. My main claim (...) is that Leśniewski built his characteristica universalis following the conditions of de Jong and Betti’s Classical Model of Science (2008) to an astounding degree. While showing this I give an overview of the architecture of Leśniewski’s systems and of their fundamental characteristics. I suggest among others that the aesthetic constraints Leśniewski put on axioms and primitive terms have epistemological relevance. (shrink)

Stanislaw Lesniewski’s interests were, for the most part, more philosophical than mathematical. Prior to taking his doctorate at Jan Kazimierz University in Lvov, Lesniewski had spent time at several continental universities, apparently becoming relatively attached to the philosophy of one of his teachers, Hans Comelius, to the chapters of John Stuart Mill’s System of Logic that dealt specifically with semantics, and, in general, to studies of general grammar and philosophy of language. In these several early interests are already to be (...) found the roots of the work that was to occupy Lesniewski’s life: a search for a definitive doctrine of what sorts of things there are in the world, or better, of what language must be like if it is adequately and efficiently to represent the world. (shrink)

"Lesniewski defined ontology, one of his three foundational systems, as 'a certain kind of modernized 'traditional logic' [On the foundations of mathematics (FM), p. 176]. In this respect it is worth bearing in mind that in the 1937-38 academic year Lesniewski taught a course called "Traditional 'formal logic' and traditional 'set theory' on the ground of ontology"; cf. Srzednicki and Stachniak, S. Lesniewski's Systems. Protothetic, 1988, p. 180. On this see Kotarbinski Gnosiology. The scientific approach to the theory of knowledge, (...) 1966, pp. 253-54 [the Polish original was published in 1929], which Lesniewski praised in [FM]: see in particular pp. 373 ff. Kotarbinski noted that Lesniewski "calls his system 'ontology' in harmony with certain terms used earlier (as in.. (shrink)

The aim of this paper is to provide a proof-theoretic characterization of relevant logics including fusion and fission connectives, as well as Ackermann’s truth constant. We achieve this by employing the well-established methodology of labelled sequent calculi. After having introduced several systems, we will conduct a detailed proof-theoretic analysis, show a cut-admissibility theorem, and establish soundness and completeness. The paper ends with a discussion that contextualizes our current work within the broader landscape of the proof theory of relevant logics.

This paper is a contribution to the reconstruction of Tarski’s semantic background in the light of the ideas of his master, Stanislaw Lesniewski. Although in his 1933 monograph Tarski credits Lesniewski with crucial negative results on the semantics of natural language, the conceptual relationship between the two logicians has never been investigated in a thorough manner. This paper shows that it was not Tarski, but Lesniewski who first avowed the impossibility of giving a satisfactory theory of truth for ordinary language, (...) and the necessity of sanitation of the latter for scientific purposes. In an early article (1913) Lesniewski gave an interesting solution to the Liar Paradox, which, although different from Tarski’s in detail, is nevertheless important to Tarski’s semantic background. To illustrate this I give an analysis of Lesniewski’s solution and of some related aspects of Lesniewski’s later thought. (shrink)

Formalism used by Leśniewski to present mathematical theory is called a radical one. According to the author, it is the implementation of the postulates of the so-called formal arithmeticians. Mathematical theory is presented as a pure game of formulas devoid of content. It is governed by the precise rules described in the metalanguage. The author stresses the difference between Leśniewski’s and Hilbert’s mathematical approaches.

Following an idea first proposed by Jerzy Wróblewski, this paperexamines the usefulness of formal logic for comparative legal analysis. Subject of the comparison are the doctrines of mistake and attempt in Germanand English criminal law. These doctrines are distinguished by the interaction of deontic, epistemic and alethic modalities. I propose a purely extensional logic which is based on Leśniewski’s substitutional interpretation ofquantification to analyse differences in the logical structure of the variouscriminal law doctrines.

Leśniewski’s metalogic is often considered to be difficult to understand because it differs greatly from its standard formulation. In this paper I try to explain the reasons of these idiosyncrasies. I claim that they have mainly two sources. First of all there is Leśniewski’s conviction that a formal system should be conceived as a set of concrete marks that can always physically and syntactically be expanded by the addition of new theses. Secondly there is Leśniewski’s conviction that (...) definitions should neither be formulas belonging to the metalanguage, nor deduction rules, but formulas belonging to the object-language and expressed with the help of the biconditional functor. The realisation of the first point is linked to the second one in so far as the metalinguistic rule for the writing out of definitions has to be formulated in a way that makes it possible to build the formal system in agreement with Leśniewski’s conception. While explaining these points I give an overview of the main peculiarities of Leśniewski’s metalogic. (shrink)

The paper provides a new and detailed critique of Barker and Dowe’s argument against multi-location. This critique is not only novel but also less committal than previous ones in the literature in that it does not require hefty metaphysical assumptions. The paper also provides an analysis of some metaphysical relations between mereological and locational principles.

Sobocinski in his paper on Leśniewski's solution to Russell's paradox (1949b) argued that Leśniewski has succeeded in explaining it away. The general strategy of this alleged explanation is presented. The key element of this attempt is the distinction between the collective (mereological) and the distributive (set-theoretic) understanding of the set. The mereological part of the solution, although correct, is likely to fall short of providing foundations of mathematics. I argue that the remaining part of the solution which suggests (...) a specific reading of the distributive interpretation is unacceptable. It follows from it that every individual is an element of every individual. Finally, another Leśniewskian-style approach which uses so-called higher-order epsilon connectives is used and its weakness is indicated. (shrink)

Two fusions can be in the same place at the same time. So long as a house made of Tinkertoys is intact, the fusion of all its Tinkertoys parts coincides with the fusion of it walls and its roof. If none of the Tinkertoys is destroyed, their fusion persists through the complete disassembly of the house. (So the house is not a fusion of its Tinkertoy parts.) The fusion of the walls and roof does not (...) persist through the complete disassembly because the walls and the roof themselves do not persist. (So the walls and the roof are also not fusions of their Tinkertoy parts.). (shrink)

I criticise a paper by Peter Forrest in which he argues that a principle of unrestricted countable fusion has paradoxical consequences. I argue that the paradoxical consequences that he exhibits may be due to his Whiteheadean assumptions about the nature of spacetime rather than to the principle of unrestricted countable fusion.

It was one of Brentano’s central ideas that all judgements are at bottom existential. In his Psychology from an Empirical Standpoint he tried to show how all traditionally acknowledged judgement forms could be reinterpreted as existential statements. Existential propositions, therefore, were a central concern for the whole Brentano School. Kazimierz Twardowski, who also accepted this program, introduced the problem of the existential reduction to his Polish students, but not all of them found this idea plausible. In 1911 Stanisław Leśniewski (...) published a paper under the title “A Contribution to the Analysis of Existential Propositions” where he criticised Brentano’s translation. According to Leśniewski the consequences of Brentano’s program would be absurd because according to Leśniewski all positive existential propositions are analytically true and all negative ones are contradictory. In his later works Leśniewski repudiated all his early writings (1911–1914) as philosophically immature and formally imprecise. “[…] I regret that they have appeared in print,” he writes, “and formally ‘repudiate’ them herewith […]”. But in spite of this severe assessment, these early papers are worth considering not only from a historical standpoint. As we will see, Leśniewski’s critique of Brentano is unsound, but it casts an interesting light on his understanding of certain basic metaphysical concepts. (shrink)

In “Tropes and Ordinary Physical Objects”, Kris McDaniel argues that ordinary physical objects are fusions of monadic and polyadic tropes. McDaniel calls his view “TOPO”—for “Theory of Ordinary Physical Objects”. He argues that we should accept TOPO because of the philosophical work that it allows us to do. Among other things, TOPO is supposed to allow endurantists to reply to Mark Heller’s argument for perdurantism. But, we argue in this paper, TOPO does not help endurantists do that; indeed, we argue (...) that anyone who accepts TOPO should reject endurantism. (shrink)

Stanisław Leśniewski was one of the two originators and drivers of the Warsaw School of logic. This article describes his work chronologically, from his early philosophical work in Lvov to his highly original logical systems of protothetic, ontology and mereology. His struggles to overcome logical antinomies, his absolute commitment to logical clarity and precision, and his antipathy towards set theory made his nominalistic approach to logic among the most original of the twentieth century, while his early death and the (...) loss of his papers meant his work was only gradually discovered and appreciated outside Poland. (shrink)

With material on his early philosophical views, his contributions to set theory and his work on nominalism and higher-order quantification, this book offers a uniquely expansive critical commentary on one of analytical philosophy’s great ...

Generalising Hrushovski's fusion technique we construct the free fusion of two strongly minimal theories T₁, T₂ intersecting in a totally categorical sub-theory T₀. We show that if, e.g., T₀ is the theory of infinite vector spaces over a finite field then the fusion theory Tω exists, is complete and ω-stable of rank ω. We give a detailed geometrical analysis of Tω, proving that if both T₁, T₂ are 1-based then, Tω can be collapsed into a strongly minimal (...) theory, if some additional technical conditions hold—all trivially satisfied if T₀ is the theory of infinite vector spaces over a finite field Fq. (shrink)

This paper explores a case example of qualitative research that applied productive hermeneutics and the central concept, fusion of horizons. Interpretation of meaning is a fusing of the researchers’ and subjects’ perspectives and serves to expand understanding. The purpose is to illustrate an exemplar of qualitative research without establishing a rigid recipe of methodology. The illustration is based on in-depth observational and textual data from an applied anthropological study conducted in western Alaska with Yup’ik hunters and fishers and government (...) agency employees as they worked towards collaborative management. The metaphor of the hermeneutical circle is showcased to help the reader understand the philosophical underpinnings and the analytical processes used to realize a meaningful interpretation. A series of organizing systems for the interpretation is described, culminating in a final organizing system to communicate a fully realized understanding of collaborative management at the time. (shrink)

Même si elle est emblématique de la pensée de Gadamer, la difficile notion d’une « fusion d’horizons » a été assez peu étudiée pour elle-même. Cet article se propose d’en faire ressortir le sens, la portée, mais aussi les difficultés. Il cherche surtout à montrer en quoi cette fusion d’horizons est l’œuvre du langage (lui-même pensé à partir de sa fusion avec l’être) et dans quelle mesure on peut y voir la version gadamérienne de l’adéquation entre l’être (...) et la pensée, suivant la conception classique de la vérité, que Gadamer ne renie jamais. (shrink)

This article presents for the first time in english lesniewski's analysis of russell's antinomy as the analysis is given in lesniewski's 1914 paper "czy klasa klas, nie podporzadkowanych sobie, jest podporzadkowana sobie?" is the class of classes which are not subordinate to themselves subordinate to itself? it is shown how the concepts appearing in this paper, written in colloquial polish, were later incorporated and expressed as fundamental axioms and theorems of his theory of collective classes, mereology. in the 1914 paper (...) he asserted: i call any object p an object subordinate to a class k if in some sense of the expression "a" the following two conditions hold: 1) k is a class (of objects) "a", 2) p is an "a". using this explication of "p is subordinate to a class k," he showed that both of the following statements are false: a) the class of classes which are not subordinate to themselves is subordinate to itself, b) the class of classes which are not subordinate to themselves is not subordinate to itself; thus showing that russell's antinomy cannot be generated since its initial assumptions are false. (shrink)

A first-order formulation of Leśniewski's ontology is formulated and shown to be interpretable within a free first-order logic of identity extended to include nominal quantification over proper and common-name concepts. The latter theory is then shown to be interpretable in monadic second-order predicate logic, which shows that the first-order part of Leśniewski's ontology is decidable.

The volume collects many of the most significant commentaries on, and contributions to, Protothetic. A Protothetic Bibliography is included.