'My endeavour in these pages is to explain the main features of the method of philosophizing which we, the Vienna Circle, use, and by using try to develop further. It is the method of the logical analysis of science, or more precisely, of the syntactical analysis of scientific language.... The purpose of the book -- as of the lectures -- is to give a first impression of our method and of the direction of our questions and investigations to those who (...) are not yet acquainted with them.' -- From the Preface. (shrink)

It is the purpose of this paper to carry out a partial syntactical analysis of imperatives. Imperatives form a large body of linguistic expressions, appearing, e.g. in mathematical proofs be a continuous function!”), laws, moral injunctions, instruction, etc. For analytical purposes we distinguish between two forms of imperatives, the fiat and the directive. By a directive we mean an imperative which includes an indication of the agent who is to carry it out. For example, “Henry, don't forget to stop at (...) the grocery!” is a directive. By a fiat we mean an imperative which includes no reference to an agent who is to carry it out. For example, “Let there be light!” is a fiat. This is a distinction made in terms of meaning. If, however, proper symbolic devices were introduced for the formalization of imperatives, it could be made in a syntactical manner. Thus we could distinguish between imperatives which possess a certain operator—the directive operator formed by putting a name within square brackets—as “[Henry]!”, and imperatives which do not possess this operator, e.g. “Let it be the case that Henry does not forget to stop at the grocery!” In the following we pay attention only to fiats. This, of course, involves a great limitation of subject matter and excludes topics of great interest. (shrink)

Category Theory has developed rapidly. This book aims to present those ideas and methods which can now be effectively used by Mathe­ maticians working in a variety of other fields of Mathematical research. This occurs at several levels. On the first level, categories provide a convenient conceptual language, based on the notions of category, functor, natural transformation, contravariance, and functor category. These notions are presented, with appropriate examples, in Chapters I and II. Next comes the fundamental idea of an adjoint (...) pair of functors. This appears in many substantially equivalent forms: That of universal construction, that of direct and inverse limit, and that of pairs offunctors with a natural isomorphism between corresponding sets of arrows. All these forms, with their interrelations, are examined in Chapters III to V. The slogan is "Adjoint functors arise everywhere". Alternatively, the fundamental notion of category theory is that of a monoid -a set with a binary operation of multiplication which is associative and which has a unit; a category itself can be regarded as a sort of general­ ized monoid. Chapters VI and VII explore this notion and its generaliza­ tions. Its close connection to pairs of adjoint functors illuminates the ideas of universal algebra and culminates in Beck's theorem characterizing categories of algebras; on the other hand, categories with a monoidal structure lead inter alia to the study of more convenient categories of topological spaces. (shrink)

Philosophers writing on the subject of human action have found it tempting to introduce their subject by raising Wittgenstein's question, 'What is left over if you subtract the fact that my arm goes up from the fact that I raise my arm?' The presumption is that something of particular interest is involved in an action of raising an arm that is not present in a mere bodily movement, and the philosopher's task is to specify just what this is. Unfortunately, such (...) an approach does not take us very far, since a person could properly be said to raise his (or her) arm while asleep or hypnotized even though he (or she) would not be performing an action in the sense of 'action' with which philosophers are particularly concerned. To avoid this kind of difficulty I shall approach the subject of human action is a more academic way: I shall expound some important rival theories of human action, and introduce the relevant issues by commenting critically on those theories. One of the issues I eventually introduce is a metaphysical one. A theory of action makes sense, I contend, only on the assumption that there are such 'things' as actions (or events). After considering some key arguments bearing on the issue I conclude that, as matters currently stand in philosophy, a metaphysically noncommittal attitude toward actions and events seems justified. (shrink)