The view is advocated that to preserve a deductivist account of science against recent criticism, it is necessary to incorporate experimental error, or imprecision, in the deductive structure. The sources of imprecision in empirical variables are analyzed, and the notion of conceptual imprecision introduced and illustrated. This is then used to clarify the notion of the acceptable range of a functional law. It is further shown that imprecision may be ascribed to parameters in laws and theories without rendering the deductive structure untestable. It is claimed that this analysis explicates the relation between laws and theories in a way that invalidates certain arguments against its deductive nature.

Some philosophers have claimed that one must be acquainted with the elements of one's ontology. Also, believing that substrata and universals are required in an adequate ontology, these philosophers have claimed acquaintance with such objects. This paper attempts to analyze what is involved in such claims and to argue that they result from a number of confusions. The paper deals largely with the claim that substrata, or bare particulars, are presented since numerical difference is a simple fact that is presented. It further attempts to argue that while neither substrata nor universals, as such, are objects of acquaintance, there are some distinctions to be drawn between talk of universals as presented objects and talk of substrata being presented.

A consideration of some basic problems that arise in the attempt to provide an adequate characterization of statistical explanation is taken to show that an understanding of the nature of scientific explanation requires us to deal with the philosophical problems connected with the nature of prior probabilities.

First, a comment on a pessimistic note: Salmon says we can't be sure there is any such thing as inductive inference: in demanding that some explanations have the form of correct inductive inferences, “we may be laying down a requirement which cannot be fulfilled.” To doubt that we can fulfill that requirement is to doubt that we can formalize inductive logic. It may be true, but why begin the fight by throwing in the sponge ? It is also true that there are difficulties involved in formalizing acceptance rules for inductive conclusions, but these difficulties may be overcome. It is false to claim that we ‘cannot claim to know exactly’ what these acceptance rules are. Only two years ago I did just that. It was true that my claim was shown to be erroneous a year later, but that fate can befall almost any worthwhile claim.

This rejoinder will be divided into two parts. The first part will be devoted to what appear to be serious disagreements between Professor Kyburg and me. I shall try to show that these disagreements are far more apparent than real. The second part will contain my criticism of Kyburg's constructive suggestion on the nature of explanation.

In this paper, I shall examine attempts to furnish formal models for deductive scientific explanation. All such attempts have had certain defects. The most serious of these defects is to be found in the fact that the extant models seem to be formally restrictive in ways that do not allow any obvious generalization of their conditions which will encompass the full range of all those scientific explanations which must be considered plausible candidates for translation into deductive models.

According to Hempel, historians do not offer full-blown explanations. Rather, they typically present explanation-sketches which need filling out. On his account,

In his article “Reflexive Predictions” in a recent issue of this Journal [1], Professor Roger C. Buck refers to our theorem concerning correct public prediction of economic and, in general, social events [2]. Unfortunately he misunderstands the nature of our theorem. He begins by stipulating the infinite regress which originally led to the belief that correct public prediction in the social sciences might be impossible: the forecaster who attempts to take into account the agent's reaction to his public prediction, finds his adjusted public prediction again falsified by the agent's reaction to it, and so on ad infinitum [3]. Professor Buck then makes an admittedly tempting mistake. He argues that, provided the sequence of public predictions—each one adjusted for the agent's reaction to its predecessor—converges towards some value, correct public prediction is possible: at the end of a sequence of falsified predictions the forecaster, as it were, catches up with the agent.

In a recent paper,[3], Harold T. Walsh has argued that (1) Whewell's commentators have in the past misunderstood his use of “necessary,” that (2) Whewell's theory of necessary truth developed only gradually through thirty years of scholarly activity, finally finding a “mature” expression in Philosophy of Discovery, published in 1860, and that (3) a proper understanding of Whewell's “mature” theory of necessary truth leads to a fundamental re-interpretation of the nature of the Ideas and of their role in scientific systems—that the meaning of “necessity” as Whewell expresses it in Philosophy of Discovery leads, in short, to a new and more illuminating reading of his philosophy of inductive science. It is my view that the three propositions asserting Walsh's view are incorrect, expecially the two important and crucial ones (2) and (3). In what follows, I shall state what seem to me to be the grounds for rejecting Walsh's view that Whewell's theory of necessity was not arrived at before 1860, and hence for rejecting his interpretation of some basic aspects of Whewell's philosophy of science.

The rapidity with which new sciences are being formed and the older ones are becoming further specialized calls for a complementary effort to interrelate the sciences. A genuine synthetization must be completely open to all future discoveries and developments within science. Such an openness would be possible only if scientific understanding possesses certain invariable patterns according to which the synthetization could be constructed. Lonergan's Insight (New York, 1958) seems to have uncovered these basic and irrevisable patterns. Not only do they demonstrate the complementarity of classical and statistical methods but the isomorphic Emergent Probability operative in world-process may well provide the framework for an open synthetization. In the present essay this possibility is demonstrated by interrelating, according to it, certain generic fields of the scientific endeavor, from physics to cultural anthropology.

In his paper ‘The Gibbs Paradox and the Distinguishability of physical Systems’ (this Journal, July 1964) Robert Rosen discusses the discontinuity of the diffusion entropy S of two gases, A and B.

Professor Boring is best known for his work in the history of psychology and for good reason: his History of Experimental Psychology and his Sensation and Perception in the History of Experimental Psychology are truly impressive works. However, he has also written numerous articles in the philosophy of science, the psychology of scientific discovery, and the sociology of scientific production, but unfortunately this material has not heretofore been readily accessible. This deficiency, however, has been corrected efficiently by the recent publication of Boring's History, Psychology, and Science: Selected Papers, edited by Robert I. Watson and Donald T. Campbell. The essays in this book represent the whole range of Boring's interests and make essential reading for any serious student of the philosophy of science. Of especial value to philosophers are the essays listed under the titles “The Scientific Method” and “The Mind-Body Problem.” Since the groupings overlap, however, the following essays in other categories are also crucial: “The Nature and History of Experimental Control,” “William James and the Psychology of the Present,” and “The Influence of Evolutionary Theory Upon American Psychological Thought.” All of these essays are interesting but the ones on operationism and theory in psychology, and the one on evolutionary notions in American psychology, are classics and worth very careful consideration and comment.