1. IMPORTANCE OF THE SUBJECT In 1900, in A Critical Exposition of the Philosophy of Leihniz, Russell made the following assertion: "That all sound philosophy should begin with an analysis of propositions is a truth too evident, perhaps, to demand a proof." 1 Forty years later, the interest aroused by this notion had not decreased. C. J. Ducasse wrote in the Journal of Philosophy: "There is perhaps no question more basic for the theory of knowledge than that of the nature of 2 propositions and their relations to judgments, sentences, facts and inferences." Today, the great number of...

This book grew out of a graduate student paper 261] in which I set down some criticisms of J. R. Lucas' attempt to refute mechanism by means of G6del's theorem. I had made several such abortive attempts myself and had become familiar with their pitfalls, and especially with the double edged nature of incompleteness arguments. My original idea was to model the refutation of mechanism on the almost universally accepted G6delian refutation of Hilbert's formalism, but I kept getting stuck on questions of mathematical philosophy which I found myself having to beg. A thorough study of the...

The two volumes to which this is a preface consist of the Proceedings of the Second International Conference on History and Philosophy of Science. The Conference was organized by the Joint Commission of the International Union of History and Philosophy of Science (IUHPS) of the IUHPS, the Italian Society for Logic and under the auspices Philosophy of Science, and the Domus Galilaeana of Pisa, headed by Professor Vincenzo Cappelletti. Domus GaIilaeana also served as the host institution, with some help from the University of Pisa. The Conference took place in Pisa, Italy, on September 4-8,...

The two volumes to which this is apreface consist of the Proceedings of the Second International Conference on History and Philosophy of Science. The Conference was organized by the Joint Commission of the International Union of History and Philosophy of Science (IUHPS) under the auspices of the IUHPS, the Italian Society for Logic and Philosophy of Science, and the Domus Galilaeana of Pisa, headed by Professor Vincenzo Cappelletti. Domus Galilaeana also served as the host institution, with some help from the University of Pisa. The Conference took place in Pisa, Italy, on September 4-8,...

About a year ago I promised my friend Fischbein a preface to his book of which I knew the French manuscript. Now with the printer's proofs under my eyes I like the book even better than I did then, because of, and influenced by, new experiences in the meantime, and fresh thoughts that crossed my mind. Have I been influenced by what I remembered from the manuscript? If so, it must have happened unconsciously. But of course, what struck me in this work a year ago, struck a responsive chord in my own mind. In the past, mathematics teaching theory has strongly been influenced by a view on...

From the point of view of non-classical logics, Heyting's implication is the smallest implication for which the deduction theorem holds. This book studies properties of logical systems having some of the classical connectives and implication in the neighbourhood of Heyt- ing's implication. I have not included anything on entailment, al- though it belongs to this neighbourhood, mainly because of the appearance of the Anderson-Belnap book on entailment. In the later chapters of this book, I have included material that might be of interest to the intuitionist mathematician. Originally, I...

In this essay I am concerned with the problem of conceptual change. There are, needless to say, many ways to approach the issue. But, as I see it, the problem reduces to showing how present and future systems of thought are the rational extensions of prior ones. This goal may not be attainable. Kuhn, for example, suggests that change is mainly a function of socio-economic pressures (taken broadly). But there are some who believe that a case can be made for the rationality of change, especially in science. Wilfrid Sellars is one of those. While Sellars has developed a full account of the...

The growing disparity between the developed and the developing countries has once again rekindled the debate about the relative merits of foreign investment as means whereby the developed countries can help the devel- oping countries in both achieving a reasonable rate of growth and also from preventing the widening gap between the North and the South from widening even further. This renewed interest in the debate was most sharply highlighted at the recently concluded North-South economic summit conference at Cancun, Mexico. There, the United States took the position that massive increases in...

This book is intended as an exposition of a particular theory of time in the sense of an interrelated set of attempted solutions to philosophical problems about it. Generally speaking there are two views about time held by philosophers and some scientists interested in philosophical issues. The first called the A-theory (after McTaggart's expression A-determinations for the properties of being past, present or future) is often thought to be closer to our commonsense view of time or to the concept of time presupposed by ordinary language. It includes at least the following theses, (a) Logic...

In this book, I attempt to lay the axiomatic foundations of metaphysics by developing and applying a (formal) theory of abstract objects. The cornerstones include a principle which presents precise conditions under which there are abstract objects and a principle which says when apparently distinct such objects are in fact identical. The principles are constructed out of a basic set of primitive notions, which are identified at the end of the Introduction, just before the theorizing begins. The main reason for producing a theory which defines a logical space of abstract objects is that it may...