Karl Popper and the Social Sciences

CAUSATION, COVERING LAWS, AND REALISM

CHAPTER THREE Social Laws, the Unity of Scientific Method, and Situational Analysis This chapter continues our exploration of Popper’s wider philosophy and its implications for situational analysis, again using his response to various aspects of positivism as our guide. We will focus on the other key tenets of positivism that I have identified—skepticism toward causality, the covering-law model of explanation, and the unity of scientific method. Our main findings will concern lawlike regularities in the social world and the unity of scientific method. We will find that, despite Popper’s claims (especially his earlier claims) to the contrary, laws play essentially no explanatory role in his social science. Moreover , his claim that the methods of the natural and social sciences are essentially the same will be shown to be plausible only if their methodologies are described in a highly abstract way. When more concrete and stringent criteria are posited for the scientific method, important differences remain between natural and social inquiry. The most important difference, we shall see, involves falsifiability—and thus the very practice of situational analysis. CAUSAT ION, COVERI NG LAWS, AND REALISM Much of what Popper wrote appears completely at odds with the fifth tenet of positivism, designated in the previous chapter as a skeptical attitude toward causes. For instance, he dismissed the claim that “the aim of science is merely to establish correlations between observed events, or observations (or, worse, ‘sense data’)”(MF, 105). Popper held that the true goal of science is to discover “new worlds behind the world of ordinary experience: such as, perhaps, a microscopic or submicroscopic world—gravitational, chemical, electrical, and nuclear forces, some of them, perhaps, reducible to others, and others not” (ibid.). That claim is consistent with his critique of induction and naïve empiricism. In fact, it is merely a restatement of his realism—science attempts to discover real structures, forces, and entities that lie behind the world of 41 everyday experience. It also expresses a realist notion of causation insofar as a scientific explanation would require identifying the forces and mechanisms that produce various phenomena. Interestingly, however, Popper also embraced what I have designated as the sixth tenet of positivism—the covering -law model of explanation—and upon first inspection his notion of a causal explanation appears identical to the “standard” positivistic account (LScD, 59–62; PH, 122–124; RAS, 131–147). According to Carl Hempel, a central figure in the development of the model, a scientific explanation “may be conceived as a deductive argument” in which the initial conditions and general laws function as the premises (Hempel 1965, 336). Similarly, in The Logic of Scientific Discovery, Popper asserted that “[t]o give a causal explanation of an event means to deduce a statement which describes it, using as premises of the deduction one or more universal laws, together with certain singular statements , the initial conditions” (LScD, 59; Popper’s emphasis). Hempel cites Popper as among the principal developers of the covering-law model, and, indeed, it is sometimes referred to as the “Popper-Hempel theory” (Hempel 1965, 337).1 Popper also endorsed the symmetry of explanation and prediction —that is, the claim that to explain an event is the same as predicting its occurrence (PH, 124). Positivists embraced this account of explanation and causation because it locates causality in the logical structure of an explanation rather than in nature itself. In doing so, it circumvents the problem of identifying a “necessary connection” between events, which Hume famously demonstrated could not be uncovered by induction alone. Popper initially avoided discussion of ontological necessity or causality. In the first publication of The Logic of Scientific Discovery, he noted that the initial conditions of a covering-law explanation were “usually called the ‘cause’” and that the predictions described what was “usually called the ‘effect,’” but he added that he himself would not use such terms, apparently considering them superfluous (LScD, 60). However, he later revised his position, although one has to do a little digging outside the main text of his works to uncover the genesis of the change. In a footnote in The Open Society and Its Enemies and in an appendix added to the 1959 edition of The Logic of Scientific Discovery, Popper embraced the notion of natural necessity and announced no more hesitation in using the word “cause” to describe it (OSE II, 362–364; LScD, 421–441). Popper reached this new stance by characterizing universal laws as conjectures about the “structural propert[ies...