This book provides a detailed exposition of one of the most practical and popular methods of proving theorems in logic, called Natural Deduction. It is presented both historically and systematically. Also some combinations with other known proof methods are explored. The initial part of the book deals with Classical Logic, whereas the rest is concerned with systems for several forms of Modal Logics, one of the most important branches of modern logic, which has wide applicability.

Artykuł przedstawia interpretację Emila Rousseau jako koncepcję jednego z czterech miejsc — obok republiki, małej wspólnoty ulokowanej poza społeczeństwem i pełnej samotności — w których człowiek może wyzwolić się z alienacji. Emil żyje w społeczeństwie, ale zachowuje duchowy dystans wobec jego członków; w istocie żyje na pograniczu społeczności, bardziej obok ludzi niż z nimi. Tak jak „obcego”, o którym pisał Simmel, łączy go z jej członkami to, co wspólne wszystkim ludziom, dzieli natomiast to, co ich właśnie łączy we wspólnotę. Emil (...) jest więc obcy ludziom, ale nie jest wyobcowany, gdyż to właśnie on, a nie oni, żyje zgodnie z naturą. Jakkolwiek Rousseau zapewnia, że Emil jest potencjalnie zdolny do zajęcia wszystkich pozostałych miejsc, autor tekstu dowodzi, że kierując się zasadą dobrowolności stowarzyszeń Emil skazany jest na życie samotne, do którego jest też najlepiej przygotowany. (shrink)

First-order logic is formalized by means of tools taken from the logic of questions. A calculus of questions which is a counterpart of the Pure Calculus of Quantifiers is presented. A direct proof of completeness of the calculus is given.

This paper develops a new proof method for two propositional paraconsistent logics: the propositional part of Batens' weak paraconsistent logic CLuN and Schütte's maximally paraconsistent logic Φv. Proofs are de.ned as certain sequences of questions. The method is grounded in Inferential Erotetic Logic.

The paper contains an exposition of some non standard approach to gentzenization of modal logics. The first section is devoted to short discussion of desirable properties of Gentzen systems and the short review of various sequential systems for modal logics. Two non standard, cut-free sequent systems are then presented, both based on the idea of using special modal sequents, in addition to usual ones. First of them, GSC I is well suited for nonsymmetric modal logics The second one, GSC II (...) is devised specially for symmetric, i.e. Blogics. GSC I and GSC II are not different formalizations, from the theoretical point of view GSC I may be seen as a simplification of the more general approach present in GSC II. They are considered separately, mainly because Blogics demand different, and more complicated, strategy in completeness proof, whereas non symmetric logics are easily and uniformly characterised by means of Fitting's Consistency Properties. The weakest modal logic captured by this formalization is minimal regular logic C, but many stronger logics are obtainable by addition of suitable structural rules, which conforms to Do en's methodology. Both variants of GSC satisfy also other, besides cut-freedom, desirable properties. (shrink)

National healthcare systems in all countries do not act effectively. Therefore, especially strategies for introducing organizational innovation to public organization should be considered. The problem is how to organize the research in this field. One of the generally accepted solutions is the systemic approach to healthcare systems. In this paper multiagent systems theory and autonomous systems theory are applied to the analysis of main types of healthcare systems. Such analysis allows us to consider the system properties: the level of the (...) autonomy, energy dissipation in the system, the payoff specificity, functional role of the agents in the system, the level of the agents’ cooperation, and delays in flows of money, requests, rules, and controls. As a result, some new functionalities of the healthcare system on the national level have been found and analysed. The aforementioned parameters are good tools to analyse the system functionality. (shrink)

entailment; families of sets; logic of questions.

There are many religions in the human world, and people manifest their religiousness in many different ways. The main problem this paper addresses concerns the possibility of sorting out this complex world of human religiousness by showing that it can be phenomenologically reduced to a few very basic existential attitudes. These attitudes express the main types of ways in which a human being relates to his or herself and the world, independently of the worldview or religion professed by the individual. (...) I use Kierkegaard’s theories of the stages of existence and subjective truth as a model. The theory of the stages of existence provides five basic existential attitudes on the basis of which religious attitudes can develop: spiritlessness, the aesthetic, the ethical, religiousness A, and religiousness B. The theory of subjective truth shows how the concept of truth functions in an ethical and existential sense as the personal truth of an individual engaged in building their religious identity. In turn, I discuss the problem of the relation of Kierkegaard’s philosophy to phenomenology, briefly introduce his concept of subjective truth and the stages of existence, and show how existential attitudes can be transformed into religious ones. I also consider the problem of the demonic as the inverted order of this anthropological and existential model. Finally, I argue that the model developed herein may be useful for further research into the phenomenology of religious attitudes. (shrink)

Andrzej Klimczuk In Michał Skarzyński (ed.), Esp, Czyli Firma Na Zakrȩcie. Outplacement Dla Pracodawców. Narodowe Forum Doradztwa Kariery. pp. 137--140 (2015) .

In this paper the life phenomenon is analysed from cybernetic point of view. The Korzeniewski’s approach is discussed and complemented. The analysis is based on autonomous systems theory and information metabolism theory. Philosophical aspects of the problem are taken into consideration as well.

In this paper, the concept of structural information is presented. The mathematical foundation of the concept is put forward, and the nature of information encoded in a structure is studied. A method for calculating the amount of structural information is introduced. An application to the analysis of cognitive maps is also presented and discussed.

The author reflects on the moral attitudes displayed by Poles fighting in the Warsaw Uprising. He believes that the sacrifice and selflessness with which Varsovians battled for their city had its roots in the general mentality of the Poles, who for generations had been raised in the spirit of “mutual and willing endowment”. He also notes that the noble ideals of the wartime generations have today been largely replaced by mercenary selfishness.

Artykuł stanowi syntetyczna próbę spojrzenia na historyczny rozwój filozofii życia z perspektywy pytań o człowieka. W jej dziejowej ewolucji wyodrębniono trzy okresy z uwzględnieniem specyfiki każdego z nich. Spoiwem wszystkich odmian filozofii życia jest otwarta, dynamistyczna koncepcja człowieka, będąca częścią wizji nieustannie stającego się świata. W takim ujęciu pytanie o człowieka odnosi sie do przesłanek rozumienia: naturalnych korzeni, dziejowej egzystencji czy ładu aksjologicznego.