Carl G. Hempel has often stated that inductive-statistical explanations, as he conceives them, are inductive arguments. This discussion note raises the question of whether such arguments are to be understood as (1) arguments of the traditional sort, containing premises and conclusions, governed by some sort of inductive “acceptance rules,” or (2) something more closely akin to Carnap's degree of confirmation statements which occur in an inductive logic which entirely eschews inductive “acceptance rules.” Hempel's writings do not seem unequivocal on this issue. It is suggested that adoption of construal (2) would remove the need for Hempel's high probability requirement on I-S explanations.

Hempel's high probability requirement asserts that any rationally acceptable answer to the question ‘Why did event X occur?‘ must offer information which shows that X was to be expected at least with reasonable probability. Salmon rejected this requirement in his S-R model. This led to a series of paradoxical consequences, such as the assertion that an explanation of an event can both lower its probability and make it arbitrarily low, and the assertion that the explanation of an outcome would have qualified as an explanation of its non-occurrence as well.

We argue that if inductive explanations are to be seen as generalizations of the causal-deterministic model, or if they are to be seen as satisfying the requirement—fulfilled by the D-N model—that explanations ought to identify certain features of the universe that are nomically responsible for the explanadum event, then the high probability requirement seems to be unacceptable. If this is so, a realistically inspired theory of inductive explanation will be committed to the paradoxes that follow from Salmon's model.

Carl G. Hempel's doctrine of essential epistemic relativization of inductive-statistical explanation seems to entail the unintelligibility of the notion of objective homogeneity of reference classes. This discussion note explores the question of whether, as a consequence, essential epistemic relativization also entails the unintelligibility of the doctrine of indeterminism.

A model of causation is presented which shares the advantages of Reichenbach's definition in terms of the screening-off relation, but which has the added advantage of distinguishing cause and effect without reference to temporal directionality. This model is defined in terms of the masking relation, which in turn is defined in terms of the equivocation relation of communication theory.

The propagation of causal influences through space-time seems to play a fundamental role in scientific explanation. Taking as a point of departure a basic distinction between causal interactions (which are localized in space-time) and causal processes (which may extend through vast regions of space-time), this paper attempts an analysis of the concept of causal propagation on the basis of the ability of causal processes to transmit “marks.” The analysis rests upon the “at-at” theory of motion which has figured prominently in the resolution of Zeno's arrow paradox. It is argued that this explication does justice to the concept of the ability of causal processes to transmit causal influence without invoking anti-Humean “powers” or “necessary connections.”

In this paper, I will develop a nontrivial interpretation of Feyerabend's concept of a hidden anomalous fact. Feyerabend's claim is that some anomalous facts will remain hidden in the absence of alternatives to the theories to be tested. The case of Brownian motion is given by Feyerabend to support this claim. The essential scientific difficulty in this case was the justification of correct and relevant descriptions of Brownian motion. These descriptions could not be simply determined from the available observational data. An examination, however, of this case shows that no alternative theory is or historically was thought to be necessary in order to justify descriptions of Brownian motion that “directly” refute thermodynamics. While Feyerabend's appraisal of this case therefore is incorrect, a sense is developed in which successful alternatives lend inductive support to the correctness of refuting experimental descriptions. Crucial though to the explanation of this support is the notion of arguments that show the possibilities for improving experimental fit.

It is a traditional empiricist doctrine that natural laws are universal truths. In order to overcome the obvious difficulties with this equation most empiricists qualify it by proposing to equate laws with universal truths that play a certain role, or have a certain function, within the larger scientific enterprise. This view is examined in detail and rejected; it fails to account for a variety of features that laws are acknowledged to have. An alternative view is advanced in which laws are expressed by singular statements of fact describing the relationship between universal properties and magnitudes.

The purpose of this paper is to set forth a sense in which programs can and do explain behavior, and to distinguish from this a number of senses in which they do not. Once we are tolerably clear concerning the sort of explanatory strategy being employed, two rather interesting facts emerge; (1) though it is true that programs are “internally represented,” this fact has no explanatory interest beyond the mere fact that the program is executed; (2) programs which are couched in information processing terms may have an explanatory interest for a given range of behavior which is independent of physiological explanations of the same range of behavior.