Jan Woleński

Professor at the Jagiellonian University in Krakow and the University of Information Technology and Management in Rzeszow.

E-mail: wolenski@if.uj.edu.pl

Issue: 1:3/1:4 (The third/fourth issue)

Propositional connectives and quantifiers are logical constants without any doubt. On the other hand, we speak about first-order logic with or without identity. Even this way of speaking suggests that identity has a special status to some extent. In fact, the status of identity is controversial.

Issue: 7:4 (The twenty eighth issue)

The paper discusses the concept of adequacy central for Pertażycki’s methodology.
According to Petrażycki any valuable scientific theory should be adequate,
that is, neither limping (to broad with respect its actual scope) nor jumping
(too narrow with respect to its actual scope). Consequently, adequacy of a
theory is a stronger condition than its truth. Every adequacy theory is true, but
not conversely. However, there is problem, because scientific laws are conditionals
(implications). This suggests that adequacy is too strong conditions, because
the consequence of an implication has a wider scope than its antecedent.
Thus, laws should have the form of equivalence. The paper shows how modeltheoretic
characterization of theories allows to recognize truth and adequacy,
consistently with Petrażycki’s claims.

Issue: 8:2 (The thirtieth issue)

It is a Preface to Volume 8:2 (2019) consisting of articles presented at the International Interdisciplinary Conference anniversary of the birth of Jan Łukasiewicz, Rzeszów, Poland.

Issue: 8:2 (The thirtieth issue)

This paper discusses the main logical ideas put forward by Jan Łukasiewicz within their historical context and further development.

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Issue: 13:1 (The forty eighth issue)

After Poland gained independence in 1918, logic developed very quickly both as a scientific direction and as a taught discipline. This introduction to the special issue "Logic in Poland in the 20th Century", published in Volume 13:1 (2024) and Volume 13:2 (2024), provides the historical context for the development of logic in the interwar period.

Issue: 13:1 (The forty eighth issue)

This paper briefly discusses the relations between logic and metalogic in history. Metalogic is understood as a reflection on logic in its various senses, particularly sensu stricto (formal, mathematical) and sensu largo (formal logic plus semantic plus methodology of science). It is shown that metalogic in its contemporary understanding arose after mathematical logic had become a mature discipline. Special passage is devoted to metalogic in Poland. The last part of the paper discussed so-called logocentric predicament.

Issue: 13:3 (The fiftieth issue)

This paper investigates the basis arguments of so-called legal logic and their relation to logic in its standard meaning. There is no doubt that legal arguments belong to logic in the wide sense (sensu largo), but their reduction to schemes of formal logic (logica sensu stricto) is a controversial issue. It can be demonstrated that only some legal arguments fall under explicit rules of formal logic, that is, having a deductive character. Most such reasoning is fallible, and its correctness depends on appealing to extra-logical principles taken from legal norms. For instance, if we say, “If it is permitted more, then it is permitted less” (argumentum a maiori ad minus), we assume that the concepts expressed by the words “more” and “less” are already defined.