Srećko Kovač

Quine rejects intensional Platonism and, with it, also rejects attributes (properties) as designations of predicates. He pragmatically accepts extensional Platonism, but conceives of classes as merely auxiliary entities needed to express some laws of set theory. At the elementary logical level, Quine develops an “ontologically innocent” logic of predicates. What in standard quantification theory is the work of variables is in the logic of predicates the work of a few functors that operate on predicates themselves: variables are eliminated. This “predicate functor logic” may be conceived as a peculiar sort of Platonism - ontologically neutral, reduced to schematized linguistic forms.

The square of opposition (as part of a lattice) is used as a natural way to represent different and opposite ways of who makes decisions, and in what way, in/for a group or a society. Majority logic is characterized by multiple logical squares (one for each possible majority), with the “discursive dilemma” as a consequence. Three-valued logics of majority decisions with discursive dilemma undecided, of veto, consensus, and sequential voting are analyzed from the semantic point of view. For instance, the paraconsistent and paracomplete logics M3, M3veto and C3 are described. The distinction of designated and non-designated values is not used, and instead, the consequence relation is defined as a preservation of the minimum truth-value of the implying set of sentences. The consequence and opposition relations of the logics described are compared, and an ordering of the logics with respect to their opposition relations is established.

We claim that Kant's doctrine of the "transcendental ideal of pure reason" contains, in an anticipatory sense, a second-order theory of reality (as a second-order property) and of the highest being. Such a theory, as reconstructed in this paper, is a transformation of Kant's metatheoretical regulative and heuristic presuppositions of empirical theories into a hypothetical ontotheology. We show that this metaphysical theory, in distinction to Descartes' and Leibniz's ontotheology, in many aspects resembles Gödel's theoretical conception of the possibility of a supreme being. The proposed second-order modal formalization of the Kantian doctrine of the "transcendental ideal" of the supreme being includes some specific features of Kantian general logic like "categorical", "hypothetical", and exclusive disjunctive propositions as basic forms.

U tekstu se obrađuju Stadlerovo i Bauerovo shvaćanje i zasnivanje formalne logike. Formalna je logika u oba slučaja postavljena u duhu novoskolastičke filozofije druge polovice 19. stoljeća. Subjektivna je strana mišljenja (samosviest, djelatba) spojena s njegovom objektivnom stranom (objektivna vriednost), a logička se načela temelje na ontologijskim. Stadler se i Bauer oddvajaju od onodobnoga formalizma i logicizma, kao i od psihologizma i voluntarizma. Pritom je Bauer izrazitije ušao u razpravljanje s drugačijim shvaćanjima (psihologizam i voluntarizam u Wundta).

Wittgenstein’s “machines-as-symbols” are considered with respect to their historical sources and their symbolic and logical nature. Among these sources and precursors, along with Leonardo’s drawings of machines, there are illustrated “machine books”, a kind of book published in the period from the 16th to the 18th centuries which consist of pictures and descriptions of a variety of mechanical devices. Most probably, these books were one of Wittgenstein’s inspirations for his view of machines as components of language-games. The picture of homo volans in Vrančić’s machine book possessed by Wittgenstein is taken as an example. In particular, homo volans is shown to contain patterns of logical laws and rules and to be abstractly interpretable as a logical symbol. A machine, taken as a symbol, is shown to be a precondition of a meaningful “overview” of a mechanical work that exceeds the limits of decidability, and to possess causal features if causality is understood teleologically and in a deeper sense of a “binding” life.

Mate Meršić (Merchich, 1850-1928) sees the origin of Zeno’s paradox ‘Achilles’ in the ambiguities of the concept of the infinity. According to him (and to the tradition started by Gregory St. Vincent), those ambiguities are resolved by the concept of convergent geometric series. In this connection, Meršić proposes a general ontological theory with the priority of the finite over the infinite, and, proceeding from Newton’s concept of fluxion, he develops a modal interpretation of differential calculus.

The abstract status of Kant's account of his ‘general logic’ is explained in comparison with Gödel's general definition of a formal logical system and reflections on ‘abstract’ (‘absolute’) concepts. Thereafter, an informal reconstruction of Kant's general logic is given from the aspect of the principles of contradiction, of sufficient reason, and of excluded middle. It is shown that Kant's composition of logic consists in a gradual strengthening of logical principles, starting from a weak principle of contradiction that tolerates a sort of contradictions in predication, and then proceeding to the (constructive) principle of sufficient reason, and to a classical-like logic, which includes the principle of excluded middle. A first-order formalisation is applied to this reconstruction, which reveals implicit modalities in Kant's account of logic, and confirms the implementability of Kant's logic into a sound and complete formal system.

In the book, the decisive, foundational role of transcendental apperception for logic and transcendental philosophy in Kant is corroborated. The book contains many implicit connections with modern logic that could help a logician with a philosophical interest to gain a deeper insight into the origins and foundations of concepts such as object, truth, analyticity, identity, contradiction, judgment, existence, reference, quantification and others, as well as into the foundations and possible general features of logic. In distinction to the book, this review emphasizes the objective validity of analytic judgements and the foundational role of hypthetical and disjunctive forms of a judgment in Kant.

Faust Vrančić's (Faustus Verantius, 1551-1617) logic is analyzed in comparison to Renaissance Aristotelianism in logic with regard to the problem of determining logic, the subject of logic, and understanding the method. Vrančić's logic is compared to Markantun de Dominis' understanding of logic and to the understanding of logic in Jacopo Zabarella and in the Jesuit Renaissance tradition (P. Fonseca, F. Toletus, F. Suárez). In addition, the concept of science is discussed. "Censura logicae" published at the end of Vrančić's "Logica nova" (1616) is attributed to de Dominis.

The publication of Gödel’s Max IV contributes to better understanding of the complex development of Gödel’s philosophical thought, and, alongside the other published notebooks, it is a further contribution to modifying a conventional view on the 20th-century philosophy, where Gödel should be recognized as one of the most important and profound philosophers. Moreover, his questions, problem formulations, and ideas, particularly as presented in his philosophical notebooks, transcend the historical distance and can immediately resonate with and inspire the current philosophical research.

This book is an introduction to elementary logic (classical propositional and first-order logic), comprising brief summaries of the basics of elementary logic, with the emphasis on typical questions and procedure descriptions and with a large number of corresponding exercises and problems. Solutions are given for each problem and exercise, often with commentaries. The first part, Basics of Logic, deals with (a) formal language, models, Venn diagrams for sentences, and translation from natural into formal language and vice versa, (b) deduction and refutation methods in the format of natural deduction (Fitch and Suppes-Lemmon styles), tableau system and Venn diagrams, and (c) basic logical properties and relations (consistency, validity, consequence, equivalence, various types of opposition, logical completeness and independency, relationship between syntax and semantics). The second part, Logic in Understanding and Analysis, introduces into (a) logical approach to problem solving in concrete situations and events as presented in brief tales and anecdotes, (b) discovering the meaning, and reconstruction of logical interconnections, in ordinary, scholarly and philosophical texts, (c) application of already mastered logical tools in examining and defining further theoretical (logical, scientific) concepts and in building formal languages. The shorter third part, From the Traditional Logic, is dedicated to the traditional logic of concepts, judgements and syllogisms, largely with the use of Venn diagrams.

It is shown, first, that Georgius Benignus [Juraj Dragišić, ca 1445-1520] at the end of the 15th century almost fully disposed with the theory of the fourth syllogistic figure. Prantl's view on Benignus' logic is critically examined. Besides, Benignus' doctrines on the supposition of terms and logical consequences are examined with respect to his two versions of logic (1488/1489 and 1519) and to the main influences (e.g., Strodus, Paulus Venetus, Ferebrich, Paulus Pergolensis). A reduction of the rules of consequences of Benignus' logic 1488/1489 to the rules of logic 1519 is reconstructed. Benignus rejects the reasoning ex impossible quodlibet and e quolibet necessarium in what he defines as material consequences.

Faust Vrančić's (Faustus Verantius, 1551-1617) logic is analyzed in comparison to Renaissance Aristotelianism in logic with regard to the problem of determining logic, the subject of logic, and understanding the method. Vrančić's logic is compared to Markantun de Dominis' understanding of logic and to the understanding of logic in Jacopo Zabarella and in the Jesuit Renaissance tradition (P. Fonseca, F. Toletus, F. Suárez). In addition, the concept of science is discussed. "Censura logicae" published at the end of Vrančić's "Logica nova" (1616) is attributed to de Dominis. -- German version: 'Faust Vrančić and der Aristotelismus in der Logik', Studia historiae philosophiae Croaticae 2 (1993), 229-252).

Zlatko Posavac is one of the most thorough and deepest experts on Croatian cultural history, with a focus on aesthetics both as a theory and as realized in artistic practice. On the basis of his improved factography, he examines aesthetic phenomena through the model of meaningful-stylistic structures and epochal change. As one of the fundamental phenomena, he highlights the "prevention of free transmission of tradition" (silencing, falsifying, expulsion of truth). He introduces significant structural shifts in cultural-historical periodization.

We approach the traditional problem of the relationship between opinion and truth, objects and appearances, from the standpoint and tools of logic of belief, combining an informal and technical approach. We describe and comment on some logics of individual concepts and modes of representation, and address the question of how to explain the possibility of a contradictory de re belief integrated with the corresponding non-contradictory de dicto belief. The QB logic is proposed, where the semantic problem is resolved (1) by extending the framework and model domain with the domain of appearances, with a special S-accessibility relation among worlds, and with non-rigid interpretation of appearance names, as well as (2) redefining the concept of satisfaction (and truth), including the satisfaction of identity statements, by relativizing satisfaction to the difference between things and appearances and to the S-accessibility of different epistemic alternatives. In doing so, all worlds are classical within themselves, while inconsistency and incompleteness in beliefs stem from different ways of connecting (merging and separating) worlds in determining the satisfaction of a formula.

After delineating the corpus of Croatian philosophy, the historical and conceptual identity and continuity of Croatian philosophy are analysed with respect to several aspects: (1) the historical space and time of Croatian philosophy; (2) its socio-cultural role and character (educational, linguistic and national-political); (3) its traditions and interconnections; and (4) the idea of Croatian philosophy. Special attention is paid to the difference between Franjo pl. Marković’s views on Croatian philosophy and the present state-of-the-art. Finally, the roots of Croatian philosophy are considered at the moment of transition from myth to Christianity and in the introductory reflections of the Charter of Duke Trpimir.

Im Folgenden stellen wir drei aktuelle Forschungsbereiche zur formalen Logik bei Kant allgemeinverständlich dar und greifen dabei auf die trans zendentale Logik nur dann zurück, wenn sie ein besseres Verständnis der formalen Logik ermöglicht: Zunächst wird Kants Beitrag zur Rezeption und Weiterentwicklung von Euler-artigen Diagrammen dargestellt. Diese Diagramme wurden in den 1990er Jahren wiederentdeckt, als formales System interpretiert und werden heute insbes. in der Didaktik, in den Kognitionswissenschaften, in der Linguistik, in KI-Bereichen wie der (Logik-basierten) Wissensrepräsentation eingesetzt, und auch in der Philosophie verwendet (Kapitel 2). Mehrere Studien haben in den letzten Jahren gezeigt, dass Kant in weiten Teilen seines Systems Oppositionsverhältnisse verwendet, die der Struktur des logischen Quadrats entsprechen. Das logische Quadrat ist heute Gegenstand intensiver Forschung, da es neben der klassischen, auch die paravollständige und parakonsistente Negation abbildet (Kap. 3). Jüngst wurde zudem die Implementierbarkeit der kantischen Logik in ein formalisiertes deduktives System bewiesen. Die Bedeutung dieses Ergebnisses wird insbesondere im Hinblick auf die formalisierte Umsetzung der Sätze vom Widerspruch, vom zureichenden Grund und der Ausschließung des Mittleren erläutert (Kap. 4). Abschließend möchten wir ein paar Perspektiven für die Forschung zur formalen Logik bei Kant nennen (Kap. 5). -- Note: No financial support acknowledged by the second autor (S. Kovač).

The Zagreb Royal Academy, the successor of the former Jesuit Neoacademy, was founded in 1776 as the central institution of higher education in Croatia as part of the educational reform in the Austro-Hungarian Empire. After presenting the basic characteristics of the reform concept, the paper deals with the teaching of theoretical philosophy at the Zagreb Academy. Philosophy was taught by E. Raffay, A. Minković, G. Valičić, S. Čučić, S. Pogledić, S. Moyses, and S. Muzler until the abolition of the Academy in 1850. In the transitional period of 1773-1776, theoretical philosophy was taught by V. Kalafatić (ethics by F. Sebastijanović). Philosophy, along with other subjects (primarily mathematics, physics, and history), was studied for two years, including logic, metaphysics, moral philosophy, and empirical psychology. Textual documentation of theoretical (as well as practical) philosophy is represented by printed examination theses that were publicly defended at the Academy. The most significant systematic work of theoretical philosophy, however, is Čučić's "Philosophia critice elaborata". A new, updated bibliography of these theses is also presented in the supplement. [Zagrebačka kraljevska akademija, nasljednica prijašnje isusovačke Neoacademije, osnovana je, u sklopu školske reforme u Austrijskoj Monarhiji, 1776. godine kao središnja visokoškolska ustanova u Hrvatskoj. Nakon izlaganja osnovnih karakteristika reformske koncepcije, rad se bavi nastavom teorijske filozofije na zagrebačkoj akademiji. Filozofiju su do ukinuća Akademije 1850. godine predavali E. Raffay, A. Minković, G. Valičić, S. Čučić, S. Pogledić, S. Moyses i S. Muzler. U prijelaznom razdoblju 1773-76. god. teorijsku je filozofiju predavao V. Kalafatić (etiku F. Sebastijanović). Filozofija se, uz ostale predmete (prvenstveno matematiku, fiziku i povijest), slušala dvije godine i to logika, metafizika i moralna filozofija i empirijska psihologija. Tekstovnu dokumentaciju teorijske (kao i praktičke) filozofije predstavljaju tiskane ispitne teze koje su se na Akademiji javno branile. U dodatku ,se donosi i nova, dopunjena bibliografija tih tezarija. Teorijski je međutim najznačajnije Čučićevo sustavno djelo "Philosophia critice elaborata«.]

A reconstruction of a formal logical deduction of Kant's table of judgments and of the other forms of Kant's "general logic" is proposed on the basis of Kant's texts, remarks and lectures. Logical unity of apperception is taken as the starting point and the reconstructed deduction proceeds only by means of analytic judgments. In distinction to Klaus Reich's approach, the forms of judgment are not derived from the definition of a judgment as relation, but "regressively", starting from quantity, in the order displayed in Kant's table of judgments and on the basis of the fourfold unity of apperception (analytic, synthetic, objective, necessary) [this reconstruction is summarized in the author's paper 'Forms of Judgment as a Link between Mind and the Concepts of Substance and Cause (Kant, Gödel)', 2014). The early, negative and positive, reception of Kant's logic in works of Croatian philosophers (especially, I. K. Horváth and Š. Čučić) is presented and discussed.