The relationship between a class of structural forms and a single reduced form econometric model is discussed. These are shown to be empirically equivalent. It is made clear that choice of a particular structural form for estimation, rather than another of the same class, rests on a priori heuristic and computational considerations, not on empirical or logical grounds.

Alternative scientific strategies are discussed briefly.

The Reichenbach-Grünbaum thesis of the conventionality of simultaneity is clarified and defended by developing the consequences of the Special Theory when assumptions are not made concerning the one-way speed of light. It is first shown that the conventionality of simultaneity leads immediately to the conventionality of all relative speeds. From this result, the general-length-contraction and time-dilation relations are then derived. Next, the place of time-dilation and length-contraction effects within the Special Theory is examined in the light of the conventionality thesis. The slow-transport method of synchrony is then examined in the light of these results and is shown not to provide an adequate method of uniquely determining the one-way speed of light. Finally, the general ∊-Lorentz transformations for events along the x-axis are derived from three principles: the round-trip light principle, the principle of equal passage times, and the linearity principle. These principles are shown to be independent of one-way velocity assumptions, and thus may form the basis of a Special Theory of Relativity without distant simultaneity assumptions.

Early sections of the paper develop a view of the natural numbers and a view of counting which are suggested by the remarks of several modern philosophers. Further investigation of these views leads to one of the main theses of the paper : a special kind of quantifier, the “numerical quantifier” is essential to counting. The remainder of the paper suggests the rudiments of a new view of the natural numbers, a view which maintains that numerical quantifiers are one kind of natural number.

This paper discusses the D-N model of scientific explanation. It is suggested that explanation is a part of assertive discourse where certain principles must be observed. Then use is made of the relation between the informative content and logical content of a sentence (as shown, for instance, by Popper) to draw some of the conditions necessary for a sound model. It is claimed that the conditions of the model proposed in the present paper exhaust the insights of the papers in the literature, solve the difficulties encountered by other authors, but have some damaging consequences on the D-N model of scientific explanation.

Many philosophers have maintained that secondary qualities are private mental entities. In this paper I use the discussions of H. A. Prichard, Berkeley and G. E. Moore on the status of secondary qualities to bring out the assumptions that underlie this view. One of these is that secondary qualities are particular. I show that Prichard holds these assumptions and then I attempt to diagnose why he holds them. In the course of this diagnosis I explore several senses of ‘dependent’ which play a role in this view. Finally, I show that a causal dependence of secondary qualities upon the perceiver will not lead to the conclusion that secondary qualities are private unless the philosophical thesis that they are particular is already assumed.

If the problem of induction were soluble, it should be solved inductively: by observing how scientists observe, etc. The fact is that scientific research is successful, and the real question is, will it be so in future? If there is a formula of induction by which success is achieved, then by this formula we can say, as long as it will be used science will succeed. If there is no formula it looks as if future success in scientific research is most doubtful. Hence, a transcendental argument for induction goes, there is an inductive formula. Since, however, such a view of induction is rejected even by inductivists as naive, the argument collapses. Hence the question is, on what basis do we project the future success of science? My answer is that this future success is built into our social institutions and is partially institutionally safeguarded.

In [2] Hempel and Oppenheim give a definition of “explanation” for a certain formal language. In [1] Eberle, Kaplan, and Montague prove five theorems demonstrating that the Hempel and Oppenheim definition is not restrictive enough. In [3] Kim proposes two further conditions to supplement the Hempel and Oppenheim definition in order to avoid the objections posed in [1]. In this paper it is shown that the definition of Hempel and Oppenheim supplemented by Kim's conditions is open to a trivialization very analogous to that given in [1].

The meaning and justification of the requirement of total evidence are examined. It is argued that there are several significantly different interpretations of the requirement, but each interpretation makes the requirement highly suspect. For any of the usual interpretations of the requirement, it would be quite unreasonable to conduct inquiry in such a way as to fulfill it. It is then suggested that the rational inquirer should seek the optimal amount of evidence, rather than all the evidence. This raises the problems surrounding the idea of scientific or epistemic utility.

The main argument of this paper is that an evaluation of the overall explanatory power of a theory is less problematic and more relevant as an assessment of the state of knowledge than evaluation of statistical explanations of single occurrences in terms of likelihoods that are assigned to explananda.

In “Induction and Objectivity” [1], F. John Clendinnen puts forwards a vindication of induction. I wish to argue that the vindication fails. As Clendinnen's argument is complex and presents certain difficulties it is necessary and only fair to quote his summary of it ([1], p. 218).

Frank Jackson's criticisms have helped me recognize some of the weaknesses in my proposed vindication of induction. The core of the argument I offered was that induction is the only method of predicting which is based in a nonarbitrary way on the facts. I still believe that this is so and that because of this property induction is the only reasonable way of predicting. However I now recognize defects in the argument by which I attempted to establish that the uniqueness of this property to induction constitutes its justification.