The recent far-reaching developments of Physics have produced the widespread impression that all those ideas of mechanics and mechanism, which were so influential in the nineteenth century, have now been completely abandoned, because they have proved to be quite inadequate as explanations, or even as mere descriptions, of the ultimate constitution of the physical world. “Has not modern physics”, asks Prof. Millikan, “thrown the purely mechanistic view of the universe root and branch out of its house?“ It is frequently contended, still further, that the place of these concepts has been taken by others, very closely approximating to biological, or even to psychological, interpretations of all natural phenomena; the physics of today, in short, and yet more of tomorrow, is essentially non-mechanical.

The sub-title of this paper is not an apology, but is an “apologia”: the paper is an “essay” in the etymological sense, because, so far as I know, nothing better is possible in the present state of inquiry into the no-man's-land lying between official logic and official linguistics. In trying to write on logico-linguistics for years I have been saved from despair many times by the confession of an eminent mathematician: Professor E. T. Bell, in his little book The Queen of the Sciences, after a particularly difficult passage blurts out: “This sentence is riddled with inconsistencies. It is a fair sample of the difficulties of talking sense about the foundations of reasoning,—mathematical or other.” (P. 136.) The present essay is emphatically concerned with ‘the foundations of reasoning’.

For some time there have been appearing in the philosophical literature hints and suggestions that the so-called “problem of the external world” should be abandoned, not primarily because it is of little pragmatic significance, but rather because there is really no such problem to be solved. The publication of Reichenbach's Experience and Prediction has now stimulated a resurgence of these suggestions. In the course of his discussion of the book in the April Philosophy of Science Professor Ernest Nagel has taken occasion to argue briefly that this problem, which Reichenbach attempts to solve, cannot even be stated unless one assumes its solution. And in a similar vein more recently Dr. William Barrett has also criticized Reichenbach and has then gone on to present certain fundamental logical considerations which, it is alleged, guarantee that the expression “Is there an external world?” cannot designate a legitimate philosophical problem. The situation, as he describes it, is as follows. The sentence “There is an external world” or the equivalent sentence “There is a physical object” can be confirmed in a physicalistic language only if one assumes the existence of certain physical objects. This procedure is of course circular. These sentences cannot therefore be confirmed, and, since the verifiability theory of meaning is accepted, the questions derived by transferring them into the interrogative mood cannot be meaningfully asked. A similar result is asserted to follow if one employs a perception language for science in place of a physicalistic language, since there is a parallelism between these two languages such that for every expression in the one there will be a corresponding expression in the other.

In July, 1939, a celebration was held at Leland Stanford University to commemorate the hundredth anniversary of the discovery that the cell is the basic unit of all living tissue. Today we are beginning to realize and to appreciate the fact that the symbol is the basic unit of all human behavior and civilization.

A common dictum or assumption in contemporary scientific and philosophical circles is that, if values are at all verifiable in any significant sense, they are less verified and less verifiable than facts. Esthetic and moral values in particular are regarded as less verifiable than scientific facts. It is frequently said that esthetic and moral “facts” and values are essentially and finally a matter of private preference or arbitrary social agreement whereas scientific facts are in the last analysis determined and underwritten by the actual nature of events and relations themselves. Yet in opposition to what may thus appear to be the chief current of contemporary opinion, some thinkers follow mainly in the tradition of Kant, Lotze, and Ritschel. They claim for values, including moral and esthetic values, a unique objectivity and validity.

Strange as it may seem, the traditional principle of causality is based on two contradictory assumptions, both of which are generally accepted, explicitly or implicitly, by the contemporary physicists as well as philosophers. That they are not always willing to acknowledge this paradoxical fact, does not save them from the perplexing situation. The two assumptions, in brief, are:

(1) That nothing can act at a distance or across an interval of time, without something mediating between the bodies or events; and

(2) That every cause precedes its effect and may be located at a distance from it.

The Trobriand Islanders about whom this study-is concerned, have been studied intensively by Professor Bronislaw Malinowski, who has published his results in several monographs. This essay is based entirely on his writings. It does not add any material to what Professor Malinowski has presented. It tries, rather, to formulate what is not explicitly stated;— the logical and ethical implications of the customary behavior of the Trobrianders. If at times I venture to disagree with Professor Malinowski's own deductions, it is only because, in presenting the material with such a wealth of pertinent detail and emotional association, he has made it possible for his readers to draw conclusions as valid as his own.

Charles Peirce was one of those rare individuals, an expert logician who is at the same time an experienced practical scientist. His logical acumen was apparent even to his contemporaries; while an early training in chemistry, astronomy, geodesy and optics, left him, as he declares, “saturated through and through with the spirit of the physical sciences.“ One is therefore hardly surprised to discover that he was deeply interested in scientific methodology—particularly in the logic of induction. Indeed, it would not be an exaggeration to say that some of his most significant contributions to philosophy were made in precisely this field. No apology is thus required for devoting attention to them. In the present paper I want to sketch his treatment of induction very briefly, and attempt a tentative estimate of its validity.

The late Victorian novelist George Gissing wrote: “I hate and fear ‘science’ because of my conviction that for a long time to come if not forever, it will be the remorseless enemy of mankind. I see it destroying all simplicity and gentleness of life, all beauty of the world; I see it restoring barbarism under the mask of civilization; I see it darkening men's minds and hardening their hearts; I see it bringing a time of vast conflicts which will pale into insignicance ‘the thousand wars of old’, and, as likely as not, will whelm all the laborious advances of mankind in blood-drenched chaos”. The German philosopher Schelling protested against “that blind and thoughtless mode of investigating nature which has become generally established since the corruption of philosophy by Bacon and of physics by Boyle and Newton”.

No account of the development of contemporary empiricism is adequate which neglects the writings and the influence of Charles Peirce. Although he is not easily pigeon-holed and can not be claimed as the exclusive property of any school or movement, it is appropriate that the hundredth anniversary of his birth should be commemorated at this Congress. For the movement of which it is a manifestation is engaged in a coöperative, intensive cultivation of the methods of the sciences with the help of the most advanced tools of modern logic; and Peirce's intellectual career was also a single-minded devotion to that task. It is fitting, also, that his birth-year be celebrated at Harvard by an international congress. For although he was denied the privilege of teaching at this university, much of his influence was propagated by William James and Josiah Royce, two of its great teachers; and however much he may have suffered from neglect during his life-time, his work surely merits recognition from a movement not confined by national bounds. It is characteristic of the best established sciences that though individuals may pursue researches in them independently of one another, the conclusions reached tend to support each other and to converge toward a common stream of sound beliefs; and such convergence is indeed the sole identifiable warrant for the confidence that some measure of the truth has been attained. It is therefore a happy sign that so many of the central ideas of the present movement have been independently developed on both sides of the Atlantic. One is not minimizing the contributions of the Vienna Circle in pointing out that many of its recent views have been taken for granted for some time by American colleagues, largely because the latter have come to intellectual maturity under the influence of Peirce.

Empirical ethics, as the term is used in this paper, may be understood as the study of moral practice and of the moral judgments employed within such practice. One aspect of such an ethics is the analysis of the meaning of terms employed in moral judgments. In this study we are concerned with the relations between the rules of usage for such terms as “good”, “interest”, “value”, and others. But these rules of usage are not to be thought of as merely semantical; rather, they are rules which state how the terms are to be used or interpreted if certain results are to be produced in specified kinds of moral situations. That is to say, since moral judgments and their constituent terms perform an important instrumental role within moral practice, it is possible both to formulate rules for the use of these instruments, and also to study the relations between these instruments (i.e., terms) which result from the application and use of these rules.

At the end of the last century, there began a movement away from traditional philosophy and towards a closer contact of philosophical thought with empirical science. Philosophers following this course were met halfway by groups of scientists, mostly physicists and mathematicians, who in their own field had found themselves face to face with problems which traditionally belonged to philosophy. But since neither of these two groups was inclined to respect conventional boundaries, they joined forces and the result of their endeavors proved challenging to both philosophy and science. Various aspects and representative theses of this movement are known to-day as logical positivism, operationism, physicalism or scientific empiricism. For the movement as a whole, however, the term logical positivism is now becoming generally used. The present paper should be considered as a selective and partly historical survey of the methodological discussion in psychology from the standpoint of logical positivism.

The philosophy of science embraces the metaphysical, epistemological and methodological problems which arise in the study of the special sciences and perhaps no branch of the philosophy of science is more deserving of careful investigation than the borderline discipline between philosophy and scientific psychology. The philosophical problems resulting from the impact of psychology upon philosophy include such traditional problems as the existence, nature and origin of consciousness, the relation of the conscious to the unconscious and subconscious mind, the nature and continuity of the self, and the relation of consciousness to its neural conditions. All these problems originate in empirical psychology and are soluble, if at all, only by appeal to psychological evidence and thus through the cooperative efforts of the philosopher and the psychologist. Unfortunately the gulf between philosophers and psychologists is as wide if not wider than that which exists between philosophers and other groups of scientists. The chief obstacle to a philosophical psychology is the alienation of psychology from philosophy which followed the attainment by psychology of its status as an independent science. Psychology as a young and vigorous science, revolting against the parental restraint of philosophy, utterly repudiated philosophy and philosophical modes of thought and, at the same time, philosophy on its side breathed a sigh of relief to be rid of a difficult and recalcitrant offspring. Thus psychological science became more hostile to philosophy than her elder sister sciences, and philosophy went its own speculative way in utter disregard of scientific psychology. Indeed “Psychologismus” has become among philosophers a term of such severe reproach that to refute a philosophical position in certain quarters one need only demonstrate that it is psychological in its origin and foundation. Thus the revolt of psychology against philosophy, natural and inevitable though it was, has been so violent and prolonged as to be detrimental to both psychology and philosophy alike.

The ability to predict events within its field indicates that a science has reached a high level of development, that its essential facts stand in systematic relationship to each other. It is important to note that prediction does not always culminate in control, but effective control is impossible without it. Thus, medicine can predict the course of certain fatal diseases with which it is unable to cope, and the astronomer can forsee eclipses and other cosmic events, yet remain powerless to intervene. Since events occurring at the human level are essentially the products of human effort and experience, it is reasonable to suppose that greater predictability in the social sciences will enhance man's control over his destiny as a social being.

If the truth of a given sentence, ‘P’ depends upon a certain non-linguistic fact, P then, how is the P without inverted commas involved in the statement, “ ‘P’ is true when P“? How is ‘P’ related to P? My answer suggests that any discussion of these questions leads inevitably to the ancient problem of particulars and universals.

There are no new fallacies under the sun, any more than there are any new methods of reasoning. Therefore, the Fluxive Fallacy is nothing new. Yet, pointing out the Fluxive Fallacy and giving it a name has a distinct advantage in that it directs one's attention to errors which, without the advantage of a definite name and description, might pass unobserved.

The sub-title of this essay might very well be: “A Study in the Biology and Mechanics of Historical Research and Interpretation”. A study in biology because historians can be divided into two classes: invertebrates and vertebrates. The invertebrate historians are those who have inarticulate major premises; the vertebrate historians are those having articulate major premises. A study in mechanics because analysis of historical thought reveals that the principle of least action holds literal sway so far as many historians' critical awareness of their assumptions is concerned.

It is frequently supposed that there exist propositions of a kind appropriately designatable as “self-contradictory”; and in this paper I propose to examine this supposition. It may first be pointed out that some philosophers use the word “proposition” in such a sense that to say there exist self-contradictory propositions is unquestionably to say what is true. They give it such a usage (which they claim to be its only significant one) as to make it synonymous with “declarative sentence”; so that a self-contradictory proposition would be a sentence of the general form s · ~s, and the supposition (a) that there are self-contradictory propositions would be equivalent merely to the supposition (b) that there are sentences of the form s · ~s. In this sense of “proposition” it seems quite plain that there are self-contradictory propositions. But it is not this usage of “proposition” with which I shall be concerned in this paper; rather, my concern will be with the usage given it, whether significantly or not, by philosophers like Mr. Russell, who hold that propositions are what literally significant declarative sentences stand for, or express.