A series of explanatory hypotheses are examined under the assumption that the logical structure of function attributions is dependent on the methodological constraints which these hypotheses conform to. Two theses are argued for: (1) Given these methodological constraints, if something has the function of doing Y, then normally it is the only kind of thing that can do Y in that kind of system. (2) What distinguishes function attributions from causal attribution is not that function attributions explain the etiology Of the causally efficacious object, as Wright has suggested. The distinction lies rather in that the object's having the effect, which is attributed to it as its function, must figure in the explanation of why it does what it does to achieve that effect.

Wesley Salmon has recently proposed a new theory of scientific explanation based on a model which he calls the statistical-relevance model. It is intended primarily as an account of the structure of explanations of particular events—explanations which, according to Salmon, are very often motivated largely by practical concerns. Two important features of this account are the concepts of homogeneity and screening off. In this paper we argue that the employment of these two concepts (which, in fact, are intimately connected) is fundamentally at odds with the desire to capture everyday explanations of the practical sort, and that it leads instead to an account in which the only satisfactory explanations are those expressed in the very deepest physical terms.

When an experimenter uses the experimental method to investigate the effects of the experimenter's expectancy it may be that this research, too, is affected by his expectancy and thus there is an expectancy paradox. To the extent that the experimenter expectancy effect accounts for the variation in the dependent variable and is general, that is to say, universal in psychological research, the expectancy paradox is ineluctable. However, an analysis of the research reviews extant in this area yields the conclusion that expectancy effects are neither inexorable nor highly general in psychological research and this provides the basis for its extrication from the expectancy paradox.

The applicability of Nagel's concept of theory reduction, and related concepts of reduction, to the reduction of genetics to molecular biology is examined using the lactose operon in Escherichia coli as an example. Geneticists have produced the complete nucleotide sequence of two of the genes which compose this operon. If any example of reduction in genetics should fit Nagel's analysis, the lactose operon should. Nevertheless, Nagel's formal conditions of theory reduction are inapplicable in this case. Instead, it is argued that genetics has been partially reduced to molecular biology in the sense of token-token reduction.

I argue against the currently popular view that a radical change in theory affects the meaning of theoretical terms, and hence render pre- and post-shift theories incomparable. I first show how to pose the meaning-change issue without appeal to meanings reified. I contend that arguments against theory-neutral observation languages are faulty, but that even if they were sound, there are semantic devices that allow a theory to refer to the factual basis of a competitor. This suggests a picture of science as the accumulation of truths, with each successive stage being more stable.

The issue of the conventionality of geometry is considered in the light of the special theory of relativity. The consequences of Minkowski's insights into the ontology of special relativity are elaborated. Several logically distinct senses of “conventionalism” and “realism” are distinguished, and it is argued that the special theory vindicates some of these possible positions but not others. The significance of the usual distinction between relativity and conventionality is discussed. Finally, it is argued that even though the spatial metric within an inertial reference frame is euclidean, it is impossible to define unique objects which can serve as the relativistic surrogates of the spatial points of classical geometry.

Wesley C. Salmon (1977) has written a characteristically elegant and ingenious paper The Curvature of Physical Space'. He argues in it that the curvature of a space cannot be intrinsic to it. Salmon relates his view that space is affinely amorphous to Grünbaum's view (Grünbaum 1973, esp. Ch. 16 & 22) that it is metrically amorphous and acknowledges parallels between the arguments which have been offered for each opinion. I wish to dispute these conclusions on philosophical grounds quite as much as on geometrical ones. Although I concentrate most on arguing for a well defined, intrinsic affinity for physical space the arguments extend easily to support a well defined, intrinsic metric.