In the paper, an analysis of concepts of category and categorization is presented. The point of departure of this analysis is J. Jadacki’s explication of the concept of category. Weak points of his explication are indicated and then a redefinition of “category” is prepared; it is based on the concept of determining properties.Introducing the concept of categorization, the author distinguishes two kinds of categorizations: natural and methodological ones. In this context, the problem of methodological reduction is briefly discussed.

The aim of the article is to present remarks concerning Susan Haack’s understanding of philosophy of logic. At the beginning, in the form of questions the area of problems tackled by philosophy of logic is indicated. Determination of the range of logic, that is differentiating logic from non-logic (the logical system from the formal system) is a priority for philosophy of logic. In the paper a critical analysis is made of the different suggestions for a demarcation line for logic that Haack discusses. Next the main ideas of philosophy of logic are presented, as seen by Haack, with special focus on two theses: about revisionability of logic and about logical pluralism. These theses appear in the context of quest for the answer to the question about correctness of logic. Also the differentiation between extended logics and deviant logics is significant here. In the final part of the paper assumptions and consequences of theses proposed by Haack are searched for and a discussion is undertaken concerning the way of justifying the obligatory character of a logic.

In the article the author undertakes a scrutiny of two different kinds of explication of evolutionary processes. One of them is explication with the use of natural selection and favorable mutations as the main factors of evolutionary changes. Another attempt at explication of those changes is the one presented by the author of neutralist theory, Motoo Kimura. It accepts accidental genetic drift and accumulation of neutral mutations as the basic mechanisms of evolution. Numerous researchers say that this is non-Darwinian theory of evolution. However, it should be noted that natural selection and the possibility of occurrence of positive mutations are not altogether eliminated from the presented picture of evolution. In the case of changes in environmental conditions the accumulated neutral changes may prove to be adaptive ones and then they will be selected by natural selection. The neutralist theory does not seem to be involved in the difficulties that the synthetic theory of evolution encounters. Such problems are meant here as the costs of the action of the natural selection, the speed of the evolution that seems to be too low for such evolutionary changes that we can see now to occur (assuming given costs of natural selection) and corpuscular polymorphism that occurs rather commonly. Also criticism of neutralist explication is presented as well as a possibility of harmonizing these two kinds of explication.

The aim of this paper is to present the main strands of the Marilyn M. Adams’s response to the problem of evil in contrast with the mainstream of the analytic theodicy. The most important difference between the standard analytic attitude to the problem of evil and that proposed by Adams is that she abandons the question about God’s reasons i.e. goods which could be morally sufficient reasons for permitting bad states of affairs to occur, especially instances of apparently pointless suffering (so-called gratuitous evils). Adams concentrates on the problem of horrendous evils i.e. evils which constitute a threat to the meaning of one’s life and prima facie undercut all positive value of one’s existence. Adams, inspired by the French thinker Simone Weil, seeks the resolution of the problem of evil in the crucified Christ’s identification with sufferers (and also in the idea of universal salvation). In the paper I analyse some weaknesses of the Adams’s theodicy, esp. I raise a query if we can give up the oldest question about evil: unde malum.

The subject of the article is a discussion of methodology of history of philosophy in Poland. In particular, the value of the inspiring role of the intellectual history in practicing history of philosophy understood as the history of philosophical culture is defended. To do this, on the one hand S. Swieżawski’s theory of philosophical historiography is referred to Swieżawski, following É. Gilson, postulated the idea of philosophically understood history of philosophy in the form of analyses of philosophical problems, significant for practicing philosophy understood systematically. However, on the other hand it has been noticed that in Swieżawski’s theory and research practice elements of history of philosophical culture can be noticed, among others those formulated and practiced by the so-called Warsaw school of historians of the idea. Considering the methodology of history of philosophy in Poland the school pointed to the significance of the history of the Polish philosophical culture. It concentrated not so much on original and influential works in the history of philosophy, as on the abounding philosophical literature. And it is this literature that without claiming epoch-making originality, is often a testimony to a reliable philosophical method; and also it has been an inspiration for the national culture.

In the article it is shown that fuzzy logics are an interesting attempt at reflecting in a formal system of “uncertainty” or “vagueness” that are sometimes encountered in human reasoning. However, they sometimes have a high price. The truth loses its traditional precision and objective quality for the benefit of intuitive and subjective opinions.The article tries to present cross-sectionally the way in which the concept of fuzziness exists in various fields. Fuzzy sets are characterized, in which the concept is shown in the most distinct and at the same time simple way. Then various aspects are shown of the issue of the ability to construct fuzzy logics. Attention is paid both to formal and semantic problems that appear in the fuzzy logic. S. Haack’s critical attitude towards fuzzy logics and J. Fox’s definition of the problem that is polemic towards it are presented, and especially his conception of the importance of the truth. This conception is an interesting attempt at harmonizing S. Haack’s critical remarks with the idea of fuzziness found in L.A. Zadeh’s works. In applications of fuzzy logic objective and subjective data are differentiated, to which this logic applies. Finally, attention is paid to extreme dissimilarity between the philosophical assumptions guiding L.A. Zadeh and authors of classical logic.

Apart from putting the theses contained in E. Agazzi’s work Why Is It Logical to Admit Several Logics? in an order and making them more distinct, an attempt is made to draw conclusions from the explicit wordings used by that author. Some theses presented in the text are shown against the views of other authors who discussed analogous problems. In this way, as it seems, modification, completing and elaborating has been possible of wordings that approve of the thesis about the existence of many logics that are contained in the analyzed text.Among others, the article emphasizes that Agazzi’s pronouncements about relations existing between standard logic and intuitionist logic cannot be accepted. Also, several remarks are made about the so-called many-valued logics. Agazzi’s theses that well constructed non-classical logics representing proper contents are necessary for representatives of various branches of knowledge is acceptable.

The aim of this article is to present an interpretative model of mystical experience, which emerges from the publications of S. Katz, professor of philosophy of religion and comparative mysticism at Boston University (USA). His view originated as a negative reaction to the conception known in the contemporary philosophical reflection on mysticism as “universal core” that promotes a conviction about the possibility of reduction of variety of mystical experiences basically to one common model. S. Katz’s point of view is pluralistic; it means he realizes impassable differences among different kinds of mysticisms. His theory is based on a notion of experience conceived as mediated. As a consequence of this assumption he presents mystical experience as a shaping process, in which decisive factors are the constructive abilities of human mind, the cultural milieu and religious traditions, where the experience takes place, and finally the experienced reality thought as conditioned contextually and subjective. The paper besides the presentational goals brings also an attempt of critical evaluation of the presented views.

The article is devoted to the problems of different kinds of logics defined as “temporal” (Temporal Logic). At present the term “temporal logic” is used to denote several mutually independent logical systems containing different specific temporal operators and being used in many different branches of knowledge. The aim of the article is to organize this issue. Parts I, II and III of the article discuss temporal logics that may be used in natural sciences (mainly physics and cosmology): tense logic, also called logic of temporal clauses, logic of time (containing time variable) and von Wright’s systems of temporal logic. In Part IV, the last part of the article, temporal systems are presented that make use of the concept of time in computer programs. Non-standard approaches have been omitted.

The problem of justification of the almighty and perfect Creator in the face of the fact that there is evil in the world was posed as early as the 3rd century BC by Epicureans and Stoics. The author of the article uses St. Thomas Aquinas’ and G.W. Leibniz’s philosophical inspirations to demonstrate by means of formal-logical means that inferring non-existence of evil from existence of God, as well as non-existence of God from existence of evil is a logical error. The analysis begins with the theory of an omniscient, infallible and omnipotent being, identified with God. “Will”, “allowance” and “objection” with respect to facts are differentiated and the law of logical squares with respect to acts of will and the iteration of states of God’s will are presented. A theistic axiology is suggested, religious fatalism and the superstition of predestination are refuted. The whole of the axiomatic calculus tends to the conclusion that evil in the world of the omnipotent Creator results from the purposefully established fortuitousness within the laws of nature, in the name of man’s freedom of choice and possibilities of development.

Most normal modal logics have been constructed as axiomatic systems rather than natural deduction. However, a lot of them have Gentzen-style or Kalish-Montague-style counterparts. Unfortunately, very few systems have Słupecki-Borkowski-style natural deduction counterparts. To fill in the gap is an aim of the present paper.The system K is developed as a Leśniewski-Borkowski-style natural deduction system in two ways. Equivalence of the systems is proved. A way is described to develop other normal systems beginning with the given system K.

The paper is concerned with Imre Lakatos’ philosophy of mathematics; it contains a presentation of Lakatos’ views and a critical analysis.Lakatos formulates his conception on the basis of a case study – namely, the history of Euler’s hypothesis concerning polyhedrons. Differentiation of Euclidean and quasi-empirical theories depending on mechanisms of justification of the theses of a given science is crucial to Lakatos’ conception. Lakatos opposes the view according to which mathematics has a Euclidean character, i.e. it is created by deducing theorems from axioms. In mathematics we deal with the mechanism of formation of explaining hypotheses for basic propositions (which are propositions accepted in informal mathematics) and in this respect it reminds of empirical sciences.The paper — apart from presenting Lakatos’ conception — also contains several critical remarks. I assert that the concept of arithmetic falsifier for multiplicity theory he introduced is not well justified. I prove the thesis that although examples on which Lakatos’ conception is based do have a historical value, they do not have any reference to contemporary mathematics. And finally I assert that it is doubtful if the way of presenting mathematical problems that Lakatos used can have a didactic value.