Some of the controversy surrounding the Duhemian claim that in science falsification is as inconclusive as verification is reconsidered. The D-Thesis, a particular version of this claim first discussed by Adolf Grünbaum, is formulated in a more precise and perspicuous fashion as a conjunction of two subtheses. Grünbaum's attempt to refute one of the subtheses by means of a geometrical counterexample and some subsequent discussions of this example are examined critically. An argument designed to prove the other subthesis is analyzed and shown to be unsuccessful. It is concluded that the D-Thesis is as yet neither proven nor refuted.

The claim that scientific explanation is deductive has been attacked on both systematic and historical grounds. This paper briefly defends the claim against the systematic attack. Essential to this defence is a distinction between perfect and imperfect explanation. This distinction is then used to illuminate the differences and similarities between Aristotelian (anthropomorphic) explanations of certain facts and those of classical mechanics. In particular, it is argued that when one attempts to fit classical mechanics into the Aristotelian framework the latter becomes structurally incoherent. It is suggested that this, together with the fact that classical mechanics embodied the first piece of perfect knowledge, accounts, in part at least, for the historical fact of the rapid demise of the Aristotelian patterns as the new science developed. On the basis of this discussion, the inadequacies of the attack on the deductive model on historical grounds by Toulmin come to be seen.

“Bohr was primarily a philosopher, not a physicist, but he understood that natural philosophy ... carries weight only if its every detail can be subjected to the ... test of experiment” (Heisenberg in [59], p. 95). As a result his approach differed from that of the school-philosophers whom he regarded with a somewhat “sceptical attitude, to say the least” ([59], p. 129) and whose lack of interest in “the important viewpoint which had emerged during the development of atomic physics” he noticed with regret ([59], p. 183). But it also differed, and to a considerable degree, from the spirit of what Professor T. S. Kuhn has called a “normal science.” Looking at Bohr's method of research we see that technical problems, however remote, are always related to a philosophical point of view; they are never treated as “tiny puzzles” whose solution is valuable in itself, even if one has not the faintest idea what it means, and where it leads: “For me” Bohr writes to Sommerfeld in 1922 ([59], p. 71) “[the quantum theory] is not a matter for petty didactic details, but a serious attempt to reach ... an inner coherence.” Emphasis is put on matters of principle ([59], p. 36) and minor discrepancies, or “puzzles” in the sense of Kuhn, instead of being deemphasized, and assimilated to the older paradigm, are turned into fundamental difficulties by looking at them from a new direction, and by testing their background “in its furthest consequences by exaggeration” ([59], p. 329). A noteworthy example of Bohr's “non-normal” and rather metaphysical approach to physics is his scepticism in the face of the success of his own atomic model.

The purpose of this note is to examine the claim made by Howard Smokler that “Goodman's paradox should be considered as an independent argument against a conception of inductive logic which makes use of rules of acceptance” ([4], p. 76).

Smokler's claim arises from his treatment of Goodman's paradox in the form given it by Israel Scheffler ([2]). Schefflerhas discussed this paradox primarily in the context of a methodology of induction which views inductive rules as rules of acceptance permitting one to assert detached conclusions. The inductive rule considered by Scheffler is described as follows:

No other branch of the philosophy of science is as backward as the philosophy of biology. When physicists or philosophers “explain biology,” they not only tend to use wrong terminologies but they usually throw away that which is typically biological. This error is second only to the even worse one of adopting vitalistic interpretations. Vitalism is now dead, as far as biologists are concerned (it seems to survive in the minds of a few philosophers), and a biologist can now talk about the differences between the philosophy of physics and the philosophy of biology without being suspected of being a concealed vitalist.

The claim that scientific explanation is deductive has been attacked on both systematic and historical grounds. This paper briefly defends the claim against the systematic attack. Essential to this defence is a distinction between perfect and imperfect explanation. This distinction is then used to illuminate the differences and similarities between Aristotelian (anthropomorphic) explanations of certain facts and those of classical mechanics. In particular, it is argued that when one attempts to fit classical mechanics into the Aristotelian framework the latter becomes structurally incoherent. It is suggested that this, together with the fact that classical mechanics embodied the first piece of perfect knowledge, accounts, in part at least, for the historical fact of the rapid demise of the Aristotelian patterns as the new science developed. On the basis of this discussion, the inadequacies of the attack on the deductive model on historical grounds by Toulmin come to be seen.

Professor Meehl [2] has pointed out a very significant problem in the methodology of psychological research, indicating that statistical tests of psychological hypotheses against a null hypothesis are loaded in favor of eventual success at rejecting the null hypothesis. In my opinion this is not, however, a contrast between physics and psychology, but rather between the method of parameter estimation and that of the null hypothesis in the tradition of Fisher. A physicist could use the null hypothesis method as well as the psychologist. The fact that he doesn't is probably related to the more advanced state of his measurement techniques and theoretical constructs.

In his recent address to the Aristotelian Society, Aurel Kolnai suggests that games exhibit what he calls a “genuine paradoxy.” I do not believe that he has shown this to be the case, even on the most permissive interpretation of what it means to be a paradox. Kolnai has, however, called attention to an aspect of games which invites further investigation, and I should like to advance the following considerations not so much as a criticism of Kolnai as an attempt to take the investigation along a path which Kolnai has indicated, but which he has not himself, in my opinion, followed. It is not that Kolnai does not say many interesting, indeed penetrating, things about games, for he does. That Kolnai's inquiry is an important contribution to the philosophy of games is not in question. What is questionable is whether paradox has very much to do with that contribution.

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.