Online research in philosophy

In the beginning, there was the DN (Deductive Nomological) model of explanation, articulated by Hempel and Oppenheim (1948). According to DN, scientific explanation is subsumption under natural law. Individual events are explained by deducing them from laws together with initial conditions (or boundary conditions), and laws are explained by deriving them from other more fundamental laws, as, for example, the simple pendulum law is derived from Newton's laws of motion.

I defend an account of explanatory depth according to which explanations in the non-fundamental sciences can be deeper than explanations in fundamental physics.

Ever since Hempel and Oppenheim's development of the Deductive Nomological model of scientific explanation in 1948, a great deal of philosophical energy has been dedicated to constructing a viable model of explanation that concurs both with our intuitions and with the general project of science. Here I critically examine the developments in this field of study over the last half century, and conclude that Humphreys' aleatory model is superior to its competitors. There are, however, some problems with Humphreys' account of the relative quality of an explanation, so in the end I develop and defend a modified version of the aleatory account.

The present essay aims to show how our thinking about explanation has evolved and where it stands now. Its first part presents how some major thinkers, from Aristotle, through to Descartes, Leibniz, Newton, Hume and Kant, to Mill, conceived of explanation. The second part offers a systematic examination of the most significant and controversial contemporary models of explanation. The first part starts with Aristotle’s conception—the thought that explanation consists in finding out why something happened and that answering why-questions requires finding causes—which set the agenda for almost all subsequent thinking about explanation. It discusses the links between laws of nature, causation and explanation in the thought of the early modern philosophers and culminates with John Stuart Mill’s first well-worked out model of scientific explanation, which was based on the idea that there is no necessity in nature and that, ultimately, explanation amounts to unification into a comprehensive deductive system, whose axioms capture the fundamental laws of nature. The second part starts with the Logical Empiricists’ attempt to legitimise the concept of causation by subsuming it under the concept of a deductive-nomological argument. It moves on to discuss the reappearance of genuinely causal models of explanation as well as the re-appearance and development of the Millian idea that explanation amounts to unification. It ends with the examination of teleological approaches to explanation.

The present paper first shows that the validity of deductive-nomological (D-N) explanations (systematizations) depends in general on the interpretation context of the predicates involved in the explanation. Therefore, no logical-semantical model can be adequate. This problem is solved by relativisation of the validity criteria on both the confirmation context and the definition context of the premisses. Based upon this, a logical-pragmatical model of D-N explanation is developed. Thereby, especially explanations of laws and global explanations are taken into consideration, since these can be regarded as prototypes of scientific explanation.

In this paper an attempt is made at developing the notion of a real and complete empirical explanation as excluding all forms of potential or incomplete explanations. This explanation is, however, no longer conceived as the proper aim of empirical science, for it can certainly be gleaned from recent epistemological publications that no comprehensive notion of a real and complete scientific explanation is likely to be constructed from within empirical science. Contrary to common understanding the empirical explanation, deductive-nomological as well as statistical explanation, is considered here only as motive of scientific activities, i.e., as common aim of a transcending cooperation of scientific and non-scientific social practice. Following from this the proper aim of empirical science now consists in the development of practically relevant explanatory theories.This redetermination of the aim of scientific activities of empirical science also means criticism of the unification of deductive-nomological and statistical explanations, as it has been proposed by Wolfgang Stegmüller in his pragmatisch-epistemische Wende. For both forms of empirical explanation must be referred to fundamentally different kinds of practical relevance, the former playing a more important role in the advancement of social practice. Stegmüller's development of a comprehensive probabilistic notion of empirical explanation, as tied up to pragmatic knowledge-situations, in a way already transcends a scientifically immanent determination of it, but he seems to have stopped halfway on the road to practically relevant empirical explanations. Several insufficiencies with his probabilistic notion of empirical explanation are shown up in this paper as a consequence of his abiding by pragmatic, and not penetrating to practical, knowledge-situations. The final result of it, however, consists in a clarification and a modification of the concept of deductive-nomological explanation, originally developed by Hempel and Oppenheim.

1 Logical empiricism: Hempel 1.1 Earlier criteria of significance 1.2 Significance as dependent on constitutive terms 1.3 Partially interpreted systems 2 Explanation 2.1 Background: deductive nomological explanation 2.2 Causal explanation 2.3 The pragmatics of explanation 2.4 Theoretical explanation 3 Confirmation 3.1 Hypothetico deductive model 3.2 The new riddle of induction 4 Scientific change 4.1 Kuhn's revolutions 4.2 Darwin's contribution 5 Realism 5.1 Constructive empiricism 5.2 Structural realism 6 Laws 6.1 Laws and mere regularities 6.2 Systems 6.3 Universals 7 Assignments..

Variational evolutionary theory as advocated by Darwin is not a single theory, but a bundle of related but independent theories, namely: (a) variational evolution; (b) gradualism rather than large leaps; (c) processes of phyletic evolution and of speciation; (d) causes for the formation of varying individuals in populations and for the action of selective agents; and (e) all organisms evolved from a common ancestor. The first four are nomological-deductive explanations and the fifth is historical-narrative. Therefore evolutionary theory must be divided into nomological and historical theories which are both testable against objective empirical observations. To be scientific, historical evolutionary theories must be based on well corroborated nomological theories, both evolutionary and functional. Nomological and general historical evolutionary theories are well tested and must be considered as strongly corroborated scientific theories. Opponents of evolutionary theory are concerned only with historical evolutionary theories, having little interest in nomological theory. Yet given a well corroborated nomological evolutionary theory, historical evolutionary theories follow automatically. If understood correctly, both forms of evolutionary theories stand on their own as corroborated scientific theories and should not be labeled as facts.

It has been the dominant view that probabilistic explanations of particular facts must be inductive in character. I argue here that this view is mistaken, and that the aim of probabilistic explanation is not to demonstrate that the explanandum fact was nomically expectable, but to give an account of the chance mechanism(s) responsible for it. To this end, a deductive-nomological model of probabilistic explanation is developed and defended. Such a model has application only when the probabilities occurring in covering laws can be interpreted as measures of objective chance, expressing the strength of physical propensities. Unlike inductive models of probabilistic explanation, this deductive model stands in no need of troublesome requirements of maximal specificity or epistemic relativization.