To explain the phenomena in the world of our experience, to answer the question “why?” rather than only the question “what?”, is one of the foremost objectives of all rational inquiry; and especially, scientific research in its various branches strives to go beyond a mere description of its subject matter by providing an explanation of the phenomena it investigates. While there is rather general agreement about this chief objective of science, there exists considerable difference of opinion as to the function (...) and the essential characteristics of scientific explanation. In the present essay, an attempt will be made to shed some light on these issues by means of an elementary survey of the basic pattern of scientific explanation and a subsequent more rigorous analysis of the concept of law and of the logical structure of explanatory arguments. (shrink)

I give some reason for accepting a form of the view that there is some logical, And not just contingent, Connection between publicly observable behavior and a person's psychological states. If my contentions are sound, They open the way to the enterprise of delineating a stratification of psychological state concepts. This involves determining which mental concepts are logically connected to observable behavior and how the other categories of mental states are specified on the basis of these.

Formal implication is usually represented by symbolization such as ‘ φx ⊃ Ψx,’ which may be read, “for all values of ‘x’, φx implies Ψx.” If the values of the variable ‘x’, in ‘φx’ and ‘Ψx’ be ‘x1’ ‘x2’ ‘x3’, etc., then … ‘φx’ formally implies ‘Ψx’ if and only if, whatever values of ‘x’, ‘xn’, be chosen, ‘φxn’ materially implies ‘Ψxn’ …However, this still leaves it doubtful which of two possible interpretations of expressions having the form ‘ φx ⊃ (...) Ψx’ is to be taken as correct. … It means one thing to say, “Every existent having the property φ … has also the property Ψ,” and it means quite a different thing to say, “Every thinkable thing which should have the property φ must also have the property Ψ.” The second of these holds only when having the properly φ logically entails having the property Ψ; when ‘Ψx’ is deductible from ‘φx’. … The first of them, however, holds not only in such cases … but also in every case where among existent things, one property is universally accompanied by another. (shrink)

Professor Reichenbach's writings have repeatedly called attention to the important rôle which probability statements play in all inquiry, and he has made amply clear that no philosophy of science can be regarded as adequate which does not square its accounts with the problems of probable inference. Recently he has brought together in convenient form many reflections on the methodology of science familiar to readers of his earlier works, and at the same time he has set himself the task of solving (...) many well-known problems of epistemology in terms of his theory of probability. His latest book is therefore of great interest, both because of the light it throws on Professor Reichenbach's own views and because it reveals the power and limitations of one approach to the problems of science. In particular, while it does not add to the details of his theory of probability worked out elsewhere, the applications Professor Reichenbach now makes of it supply fresh clues for judging its import and adequacy. The object of the present essay, therefore, is to expound a number of his views on probability and epistemology, with a view to examining his conclusions and their relevance to the problems he aims to resolve. The discussion will try to determine whether several features of his present views do not follow from assumptions which he has not sufficiently considered; whether his logical constructions do not create new puzzles; and whether a different starting-point should not be taken if the clarification of scientific concepts and procedures, to which Professor Reichenbach's devotion is as unexcelled as it is well known, is to be successfully conducted. (shrink)

The attempt to draw a clear distinction between Philosophy and the empirical sciences can almost be taken as the defining trait of the analytic movement in contemporary philosophical thought. The empirical science that has most frequently threatened to swallow up questions of particular interest to philosophers since the time of Descartes has been psychology. Characteristic, then, of analytic philosophy has been the rejection of what it terms psychologism, that is to say, the mistake of identifying philosophical categories with those of (...) psychology, whether introspective or behavioristic. It is clear that to launch an attack on psychologism, thus conceived, presupposes that one has a list of philosophical categories which one is able to identify as such; and this in turn presupposes an ability to sketch, at least in a general way, a distinctly philosophical account of these concepts, although a systematic account along non-psychologistic lines may be a distant and ill-defined goal. The analytic movement in philosophy has gradually moved towards the conclusion that the defining characteristic of philosophical concepts is that they are formal concepts relating to the formation and transformation rules of symbol structures called languages. Philosophy, in other words, tends to be conceived of as the formal theory of languages. From this standpoint, consequently, psychologism is conceived of as the psychological treatment of concepts which are properly understood as formal devices defining a mode of linguistic structure. (shrink)

Positivists and phenomenalists of all sorts maintain, and long have maintained, some variant of the following thesis concerning the existence of physical objects: Such statements as ‘There is now a wall behind my back’ are synonymous with a class of statements of which the following is representative ‘If I shall turn my head, then I shall also have the visual experience called ‘seeing a wall'.’ This amounts to proposing what many of us call a philosophical analysis of ‘exist’ or, more (...) precisely, of one meaning of ‘exist'; for the thesis implies that this verb, in the sense in which we use it when we say ‘This wall exists', is dispensable in the sense of being definable. Realists, who oppose the thesis, hold that ‘exist', in the sense mentioned, is what I would call an undefined descriptive predicate; and then they go on to recommend that instead of defining existence in terms of what we see, we had better say that we shall, if we turn, see a wall because there is a wall. Thus one could say, perhaps, that the realists wish to convert the positivistic position; instead of founding existence upon experience, they want to found experience upon existence. To be sure, this is but a bare and crudely formulated schema of an issue that has been argued for a long time. Also, contemporary analysts for the most part do not discuss the issue directly; they give their attention to preliminary and, therefore, more fundamental questions. Like experienced chess players, who know to which characteristic situations in the middle game certain openings will eventually lead, we try to convince each other of the excellence of our respective openings. There is, in particular, one fundamental or opening move that is now widely discussed and which, I believe, most of us examine with a view to the position in which we shall find ourselves—in the middle game—with respect to the realism issue. I refer to the clarification of the relations between meaning and verification or, to put it the way positivists do, to the formulation of an adequate meaning criterion. Let me indicate the connection between these questions and the crude schema I have given for the realism issue. According to current garden varieties of positivism, a statement is meaningful if it is verifiable by experience. ‘There is a wall behind my back’ is, in this view, meaningful because it is synonymous with a class of statements each of which is verifiable by future experience. More pointedly, the familiar common sense statements about the existence of physical objects are considered as meaningful because they are verifiable. This has again the subjectivistic ring realists dislike so much; so they may again be inclined to convert the positivistic position, if only tentatively and because they feel that a piece of realistic common sense would thus be preserved. But to make the conversion is to say that ‘There is a wall behind my back’ is verifiable because it is meaningful. (shrink)

Metaphysical problems may be solved by the methods of inference employed in the empirical sciences. So we are told by many realists and pragmatists, among whom may be mentioned Professors J. B. Pratt, William Savery, and Donald Williams. Mr. Williams and Mr. Pratt have argued for the use of inductive methods in establishing the existence of an external world. Mr. Savery has asserted that all philosophical inference as to matter of fact is inductive. This naturalistic attitude is by no means (...) unusual—in fact it is so common in this age in which the speculations of scientists as well as their achievements have captivated the popular imagination, that even philosophers have for the most part failed to examine its validity and presuppositions. It is the purpose of this paper to present such an examination, not of the philosophic employment of inductive methods in general, but in regard to one specific problem; namely, that of the existence of an external world. What I purpose then is to present and evaluate the view that the existence of an external world may be established by inductive methods as employed in the empirical sciences. (shrink)