Causal v. positivist theories of scientific explanation: A defense of the causal theory
Three fundamental claims are defended in this dissertation. First, the influence of Hume's epistemological program and his skepticism with respect to causal knowledge have hindered the development of an adequate theory of scientific explanation. Second, Hume's conception of causal knowledge is outdated, and knowledge of causation should be relieved of the special epistemological burden placed on it by Hume's followers. Finally, once relieved of this Humean epistemological burden, the causal theory of scientific explanation is superior to alternatives lying in the tradition of Humean positivism.
Humean positivism places severe constraints on theories of scientific explanation, and its influence on extant theories is reviewed. Recent positivist theories of scientific explanation are discussed critically, and are shown to suffer serious difficulties. Particular attention is paid to recent pragmatic theories (van Fraassen's and Sintonen's) and to Kitcher's unificationist theory.
The causal theory of scientific explanation is developed through an examination of theories of causation. Traditional views (e.g., the regularity view), recent statistical theories, and Salmon's (1984) theory of causation are rejected in favor of Cartwright's thesis that causal laws are best understood as capacity ascriptions. The essential features of scientific explanations are then outlined: most prominent are the ascription of causal capacities and the description of causal interactions. The philosophical benefits of the causal theory are also summarized.
Common objections to causal theories of explanation are treated. Of central importance is Hume's skeptical argument. Once Hume's conception of causal knowledge is modernized, however, his arguments yield no skepticism particular to the knowledge of causation: causal knowledge is as defensible as are more respectable types of empirical knowledge. Other important objections are also reviewed.
Finally, historical studies of two well-known explanatory controversies--the Jensen-Lewontin debate concerning the heritability of IQ, and a dispute about the nature of cosmic radiation--are presented. Positivist theories of scientific explanation can account for neither the origin nor the manner of resolution of these controversies. In contrast, the causal theory of explanation is shown to illuminate the controversies successfully. This success offers additional evidence in favor of the causal theory of scientific explanation.