•  5010
    Was Gaunilo Right in his Criticism of Anselm? A Contemporary Perspective
    European Journal for Philosophy of Religion 4 (2): 101--111. 2012.
    Gaunilo argued that Anselm could prove the existence of many perfect objects, for example, the happiest island, that is, happier than any other island. More formally, Gaunilo’s arguments were intended to show that the sentence “God exists‘ does not follow from premises accepted by Anselm. Contemporary versions of the ontological proof use the maximalization procedure in order to demonstrate that God exists as the most perfect being. This paper argues that this method, which is based on maximaliz…Read more
  •  357
    Truth-makers and Convention T
    Philosophical Papers Dedicated to Kevin Mulligan. 2011.
    This papers discuss the place, if any, of Convention T (the condition of material adequacy of the proper definition of truth formulated by Tarski) in the truth-makers account offered by Kevin Mulligan, Peter Simons and Barry Smith. It is argued that although Tarski’s requirement seems entirely acceptable in the frameworks of truth-makers theories for the first-sight, several doubts arise under a closer inspection. In particular, T-biconditionals have no clear meaning as sentences about truth-mak…Read more
  •  144
    Two Critical Contributions to the Problem of Truth and Meaning
    Polish Journal of Philosophy 1 (1): 137-141. 2007.
    This paper critically discusses two points concerning some recent views about the concept of truth. Firstly, contrary to Davidson, it shows that meaning of sentences cannot be explicated by T-equivalences. In particular, “is true” is an extensional predicate, but “means that” an intensional one. Secondly, the minimalist account of truth does not provide a satisfactory analysis of the concept of falsity. In this respect, minimalism does not satisfy Russell’s claim that any adequate truth-theory m…Read more
  •  122
    This paper describes and compares the first step in modern semantic theory for deontic logic which appeared in works of Stig Kanger, Jaakko Hintikka, Richard Montague and Saul Kripke in late 50s and early 60s. Moreover, some further developments as well as systematizations are also noted.
  •  104
    The History of Epistemology
    In M. Sintonen, J. Wolenski & I. Niiniluoto (eds.), Handbook of Epistemology, Kluwer Academic Publishers. pp. 3--54. 2004.
  •  94
    Polish attempts to modernize thomism by logic (bocheński and salamucha)
    Studies in East European Thought 55 (4): 299-313. 2003.
    This paper reports some attempts undertaken in Poland in the 1930s to modernize Thomism by means of modern logic. In particular, it concerns J.M. Bocheski and J. Salamucha, the leading members of the CracowCircle. They attempted to give precise logical form to the Five Ways of Thomas Aquinas. Other works concerned the concept of transcendentals, the levels of abstraction, and the concept of essence.
  •  87
    Psychologism and metalogic
    Synthese 137 (1-2). 2003.
    This paper examines two arguments againstpsychologism advanced by Frege andHusserl. The first argument says that thelaws of logic cannot be justified by thelaws of psychology, because the formerand a priori and certain, but the latterare probable only. The second argumentpoints out that the status of logicallaws as universal principles of thinking isnot intelligible on the psychologisticinterpretation of logic. The author tries toshow how to examine both arguments bymetalogical devices.
  •  76
    On the principle of the excluded middle
    with Jan Łukasiewicz and Peter Simons
    History and Philosophy of Logic 8 (1): 67-69. 1987.
    The brief article of 1910 which is translated here is, as the prefatory note explains, significant for understanding both the way in which ?ukasiewicz came to many-valued logic and the influences under which he stood at the time
  •  67
    This paper discusses the distinctions indicated in its title. It is argued that the distinction between syntax and semantics is much more important for the present situation in logic than other distinctions. In particular, doing formal syntax and formal semantics requires the use of an informal melanguage based on ordinary mathematics
  •  64
    Truth and Consistency
    Axiomathes 20 (2-3): 347-355. 2010.
    This paper investigates relations between truth and consistency. The basic intuition is that truth implies consistency, but the reverse dependence fails. However, this simple account leads to some troubles, due to some metalogical results, in particular the Gödel-Malcev completeness theorem. Thus, a more advanced analysis is required. This is done by employing the concept of ω-consistency and ω-inconsistency. Both concepts motivate that the concept of the standard truth should be introduced as w…Read more
  •  63
    Notes on Books
    Polish Journal of Philosophy 2 (1): 167-171. 2008.
  •  63
    Aletheia in Greek thought until Aristotle
    Annals of Pure and Applied Logic 127 (1-3): 339-360. 2004.
    This paper investigates the concept of aletheia in ancient philosophy from the pre-Socratics until Aristotle. The meaning of aletheia in archaic Greek is taken as the starting point. It is followed by remarks about the concept of truth in the Seven Sages. The author discusses this concept as it appears in views and works of philosophers and historians. A special section is devoted to the epistemological and ontological understanding of truth. On this occasion, influential views of Heidegger are …Read more
  •  62
    Handbook of Epistemology (edited book)
    Kluwer Academic. 2004.
    The twenty-eight essays in this Handbook, all by leading experts in the field, provide the most extensive treatment of various epistemological problems, ...
  •  57
    Józef M. Bocheński and the Cracow Circle
    Studies in East European Thought 65 (1-2): 5-15. 2013.
    Józef M. Bocheński began his philosophical career as an eclectic philosopher, then switched to Thomism and finally became a representative of the analytic school. As a Thomist he wanted to reform this orientation by the resources of modern formal logic. This tendency culminated in the establishment of the Cracow Circle (established in 1936) whose members were Bocheński, Jan F. Drewnowski, Jan Salamucha, and Bolesław Sobociński. However, the program of the Cracow Circle was rejected by most Thomi…Read more
  •  55
    Łukasiewicz and Popper on Induction
    History and Philosophy of Logic 31 (4): 381-388. 2010.
    We compare Jan ?ukasiewicz's and Karl Popper's views on induction. The English translation of the two ?ukasiewicz's papers is included in the Appendix
  •  52
    An abstract approach to bivalence
    Logic and Logical Philosophy 23 (1): 3-14. 2014.
    This paper outlines an approach to the principle of bivalence based on very general, but still elementary, semantic considerations. The principle of bivalence states that “every sentence is either true or false”. Clearly, some logics are bivalent while others are not. A more general formulation of uses the concept of designated and non-designated logical values and is captured by “every sentence is either designated or non-designated”. Yet this formulation seems trivial, because the concept of n…Read more
  •  51
    Meaningfulness, Meaninglessness and Language-Hierarchies
    Polish Journal of Philosophy 4 (2): 35-47. 2010.
    Roman Ingarden offered a strong criticism of the verifiability principle in his talk delivered at the 8th International Congress in Prague in 1934. Ingarden argued that this principle either violates itself or smuggles a hidden sense. In this paper I show that Ingarden-like arguments about smuggled (but this pejorative qualification is skipped) meaning apply not only to the criteria of sense, but also to other semantic assertions within language-hierarchies in Tarski’s sense.
  •  50
    Metalogical properties, being logical and being formal
    Logic and Logical Philosophy 10 (n/a): 211. 2002.
  •  49
    Something, nothing and Leibniz’s question. negation in logic and metaphysics
    Studies in Logic, Grammar and Rhetoric 54 (1): 175-190. 2018.
    This paper discusses the concept of nothing (nothingness) from the point of logic and ontology (metaphysics). It is argued that the category of nothing as a denial of being is subjected to various interpretations. In particular, this thesis concerns the concept of negation as used in metaphysics. Since the Leibniz question ‘Why is there something rather than nothing?’ and the principle of sufficient reason is frequently connected with the status of nothing, their analysis is important for the pr…Read more
  •  48
    What is formal in formal semantics?
    Dialectica 58 (3). 2004.
    Formal semantics is understood either as a formal analysis of semantical features of natural language or as model-theoretic semantics of formal(ized) languages. This paper focuses on the second understanding. The problem is how to identify the formal aspects of formal semantics, if we understand ‘formal’ as ‘independent of content’. This is done by showing that the form of semantical interpretation of a language L is given by its syntax and the parallelism of the signature of L and its interpret…Read more
  •  47
    Ways of Dealing with Non-existence
    Grazer Philosophische Studien 50 (1): 113-127. 1995.
    Non-existence provides big problems for ontology and modest for logic. Logical problems of non-existence consist in licensing inferences in which sentences with empty terms are involved. The standard predicate logic solves this question by presupposing that every individual constant has an object to which it refers. This means that empty domains are excluded from semantics for the first-order logic. However, there is a temptation to consider logic without existential presuppositions.The ontologi…Read more