Two ideal standard clocks, effectively isolated from interaction with other physical systems, and in a region of the universe free of gravitational fields, are assumed to move in any arbitrary manner so that they coincide on at least two occasions. In general, the reading of one of them will become retarded relative to the other in the interval between successive coincidences. This relative retardation is predicted by the restricted theory of relativity, taken together with the assumption that the ‘rate’ of a clock depends only on its velocity and not on its acceleration. The recognized procedure for calculating the retardation in terms of clock ‘rates’ is set out, and is illustrated by its application to a simple hypothetical experiment in which one clock remains at rest and the other travels away from and back to it with constant speed in a straight line.

There is nothing paradoxical in the predicted retardation as such. The so-called 'clock paradox' arises because an alternative, and apparently valid, calculation procedure, also based on clock 'rates', leads to a contradictory result. The term ‘paradox’ is something of a euphemism since the two predictions are contradictories.

It is shown that the paradox does not arise when direct use is made of the Lorentz transformation without introducing the additional, and non-essential, step in reasoning involved in utilizing the clock ‘rates’. It is then shown that the paradox arises only through using these clock ‘rates’ without due regard to the exact significance of the quantities so described; once this is recognized the paradox is resolved completely within the framework of the restricted theory, which then provides a unique and unambiguous prediction of the relative retardation.

Once the paradox is thus resolved, the general theory of relativity can add nothing significant to the analysis. It is shown that the application of the principle of equivalence is essentially trivial; in effect, Einstein and Tolman evaded the real logical issue raised by the contradictory predictions by denying the applicability of the restricted theory and then utilizing, by means of the principle of equivalence, results obtained from it. This tortuous procedure succeeded in evading the paradox rather than in resolving it; it would obviously be quite invalid were the restricted theory indeed inapplicable to the problem.

Since my discussion of an experimental arrangement of the sciences for certain practical objectives, some comment has appeared which makes it necessary to re-emphasize certain points by a further example. There seems to be something like a desire to paralyze the hand that makes arrangements for fear that undue profound metaphysical significance may be seen in a “mere” arrangement. It is the perennial fear of the a priori, the fear of a principle being invoked because of its “self-evidence”, and then turning traitor on the actual evidence. I invoke no such principle either overtly or covertly.

Lewis' argument against the Limit Assumption and Pollock's Generalized Consequence Principle together suggest that “minimal-change” theories of counterfactuals are wrong. The “small-change” theories presented by Nute do not say enough. While these theories rely on closeness between possible worlds, I base an alternative on the ceteris paribus concept. My theory solves a problem that the above cannot, and is more relevant to the philosophy of science. Ceteris paribus conditions should normally include the causes, but exclude the effects, of the negated antecedent. An example from community ecology, the debate over null models in island-biogeographical studies of competition, supports these arguments.

The following comments represent what seem to me promising lines of approach to some of the broader issues in the philosophy of logic. They are offered, it is perhaps unnecessary to say, with the intent of stimulating rather than foreclosing discussion. And if the conclusions advanced are formulated loosely and with only a crude indication of the arguments which support them, I hope that thereby they will provoke all the more the free flow of discourse which it is the object of this Conference to promote.

In order adequately to refute the charge that relativism makes against any absolute answer to problems of science, it will be necessary for us to generalize upon the principal theme and attempt a characterization of experimental methodology. Only by thus determining what constitutes experimental inquiry in general can we hope to define that particular aspect of it which involves the concept of probability.

(1) The probability of some generalizations can be lowered by positive instances.

(2) The change in probability (both degree and direction) can depend on factors other than the new evidence, the statement, and the probability of the statement given the old evidence.

If there is an essential difference as suggested in a preceding article, between the natural sciences on the one hand and the social studies on the other, in the sense that man has the power to change, and has repeatedly changed, existing social organizations, whereas he has no such power over natural phenomena, the meaning of social science must in this respect at least differ substantially from that of natural science. Elsewhere the present writer has designated society an “artificial creation,” much as the automobile or a steel mill is, i.e. made by the artifice of man. The artificial automobile or steel mill is of course fabricated in the light of the natural laws of physical science. Its construction would be impossible without a knowledge of these laws. There are also certain natural laws and tendencies in human nature and animal behavior which must serve as a foundation for any scientifically fabricated society, i.e. constructed on the basis of observation and verification of these tendencies on the one hand and a rigorous use of theory and analysis on the other. In short, despite any essential difference, as suggested, between natural and social science, the scientific method is apparently just as applicable in the one field as in the other. There is still much confusion on this score. But before pursuing further the significance of the distinction, artificial versus natural, it will be well to have before us more of what opposing schools of methodological thought in the social studies have to offer.

Scientific tradition holds that it is essential to permit individual researchers almost complete freedom in their selection of research projects. As a result, structured research planning has not played a major role in determining the course of the sciences. By “structural research planning” we mean the methodical establishment of goals, and the identification of research routines which apparently accord priority to highest value goals, while minimizing the cost and time of their attainment. With increasing competition for limited fiscal and intellectual resources this kind of planning may become more necessary. Let us cite three specific examples: First, the individual researcher is often faced with the question of how best to spend his time in pursuing a particular line of investigation. He must allocate his personal resources of time and talent to work which appears to hold the promise of highest pay-off. Second, on a larger scale, the competition for resources also raises the question of priority among alternative government-sponsored research projects. Individuals proposing equally alluring projects sometimes seek the same funds; government planners need some sort of objective criteria (hopefully based on a rational strategy) in order to judge the proposals. Furthermore, government planners face the problem of justifying their request for “big science” resources; a planning strategy which defines the use and expected output of the requested resources can help in the design and promotion of their concept. Finally, there is a growing sentiment that at least some research should be directed toward the solution of current and anticipated societal problems, to find means of circumventing or minimizing the impact of potentially dangerous problems of civilization. These needs : the choice of individual research, allocation of national resources among competing projects, and selecting research of societal importance, suggest that structured research planning might be valuable.

In a recent commendable article, Quentin Smith (1987) exposes fatal flaws in several recent attempts to demonstrate that it is logically impossible for the past to be infinite. However, his analysis of one of these flawed arguments—involving an interesting version of Russell's “Tristram Shandy paradox”—is off the mark, as I show in this paper.

Some thinkers distrust Darwinist explorations of complex human behaviors, particularly investigations into possible differences in valued skills between genders, races or classes. Such projects, it is claimed, tend to have adverse effects on people who are already disadvantaged. A recent argument by Philip Kitcher both clarifies and generalizes this charge to cover a wider genre of scientific projects. In this paper I try to spell out and analyze Kitcher's argument. The argument fails, I suggest, because some of its key premises fail to convince. My analysis focuses on relevant facts about the role of inquiry in fallibilist contexts, the texture of belief in contemporary natural science, and the moral dimension of scientific research.

Objective chance, or the “big bad bug” of David Lewis's account of Humean Supervenience forces, as is well known, is a modification of the Principal Principle. Here, I argue that standard assumptions regarding conditional probabilities entail several puzzling consequences for Lewis's New Principle, namely, an apparent requirement to account for the chance of a theory of chance. These problems, I argue, cannot be adequately answered within the received framework, and so I suggest that an interpretation of conditional probabilities in terms of Alan Hájek's recent work might go some distance toward their resolution.

When the terms ‘control’ and ‘experiment’ are used in reference to the methodological procedures of the social sciences, frequently the question is raised as to whether or not the investigator uses the terms in the same sense as the natural scientist. The purpose of this paper is to show that the social scientist has good reason to use them in the same sense and that in fact this usage is consistent with a long tradition of social research. This will be shown by an investigation of some common assumptions in the social sciences, such as, (a) the claim that the social sciences are younger than the natural sciences and that the former have depended upon the latter for methodological cues, (b) that human behavior is ultimately inexplicable and unpredictable, and (c) that the social scientist is unable to observe human behavior under controlled, experimental conditions except in trivial instances. Of course, not all social scientists make these assumptions but they occur in the literature and their significance is considerable when the scientific status of the social sciences is being discussed.

During the past half-century the patterns of publication in science have undergone radical change. A vast increment has occurred in the amount of scientific writing. And scientific findings are increasingly being disseminated through “non-traditional” publishing media such as mimeographing and microfilming. These two interrelated trends have had some notable effects upon science. 1. With the rapid increase in the number of publications the problem of maintaining continuity in science has become acute; the traditional scientific social structure seems quite incapable of accomplishing this vital task. 2. An extensive organization is developing which seeks to provide the desired continuity, but its very existence poses dilemmas for the traditional scientific order. 3. Moreover, the changing publication patterns seem to be intensifying the “schisms” between the theoretician and the specialized researcher. 4. They are also challenging the older standards for evaluating scientists. We thus hypothesize that the volume and form of communication is a significant variable inducing modifications in the scientific social system. This theoretical orientation has in part been suggested by Harold Innis (7) who, however, was concerned with broader systems—i.e., civilizations. The following analysis should point up some little-considered problems inherent in the research process.