Online research in philosophy

Aristotele. Science as a systematic explanation through causes.--Newton, I. Rules and reflections on scientific reasoning.--Carnap, R. Empiricism, semantics, and ontology.--Hempel, C. On the logic of explanation.--Nagel, E. The realist view of theories.--Quine, W. V. On the role of logic in explanation.--Harris, E. E. Method and explanation in metaphysics.--Einstein, A. Remarks on Bertrand Russell's theory of knowledge.--Sellars, W. The language of theories.--MacKinnon, E. Atomic physics and reality.--Bunge, M. Physics and reality.--Heelan, P. A. Quantum mechanics and objectivity.--Bibliographical essay (p. 285-301).

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 paper tries to provide an alternative to Hempel’s approach to scientific laws and scientific explanation as given in his D-N model. It starts with a brief exposition of the main characteristics of Hempel’s approach to deductive explanations based on universal scientific laws and analyzes the problems and paradoxes inherent in this approach. By way of solution, it analyzes the scientific laws and explanations in classical mechanics and then reconstructs the corresponding models of explanation, as well as the types of scientific laws appearing in it. Finally, it compares this reconstruction with the approaches of J. Woodward and C. Hitchcock, C. Liu and with the views of M. Thalos on analytic mechanics.

Leuridan (2010) argued that mechanisms cannot provide a genuine alternative to laws of nature as a model of explanation in the sciences, and advocates Mitchell’s (1997) pragmatic account of laws. I first demonstrate that Leuridan gets the order of priority wrong between mechanisms, regularity, and laws, and then make some clarifying remarks about how laws and mechanisms relate to regularities. Mechanisms are not an explanatory alternative to regularities; they are an alternative to laws. The existence of stable regularities in nature is necessary for either model of explanation: regularities are what laws describe and what mechanisms explain.

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.

Scientific explanation in terms of laws and initial conditions (or better, in terms of objects with powers and liabilities) is contrasted with personal explanation in terms of agents with powers and purposes. In each case the factors involved in explanation may themselves be explained, and infinite regress of explanation is logically possible. There can be no absolute explanation of phenomena, which is explanation in terms of the logically necessary; but there can be ultimate explanation which is explanation in terms of factors which themselves have no explanation. Our normal criteria of explanation suggest that the explanation of the universe lies in the action of God.

In recent years philosophy of science has seen a resurgence of interest in metaphysical issues, especially those concerning laws, causation,and explanation. Although this book takes only the latter two words for its title, it is also about laws of nature. It is divided into three sections: the first is on causation, the second is on laws, and the third is on explanation: this is entirely appropriate because the debates about them are closely related. Ever since Hume argued that causation is nothing more than regularities, laws have been more respectable than causes in philosophy. Perhaps this is also because science is replete with specially named laws which seem to play a central role in theories and explanations. Yet, as many philosophers have recently pointed out, contrary to Russell’s famous pronouncement that causation is a relic of a bygone age (quoted p. 3 by Psillos), the contemporary special sciences are very much concerned with the identification and investigation of all manner of causal structures. This raises the question of whether the apparent causal powers attributed to kinds in the special sciences are anything over and above a way of talking about the result of the operations of physical laws governing their microconstituents. Hence the logical empiricist’s project of showing how the laws of the special sciences reduce to those of physics. On their view, explanation, and in particular causal explanation, is nothing more than argument using the laws of nature as premises. However, this coveringlaw model of explanation has been subjected to intense criticism, and there have been attempts to construct alternatives that rely on the idea that to explain an event is to cite its real cause, where this cause need not be subsumed under any law. Since the demise of logical empiricism, or at least the waning of its influence, there has been a proliferation of theories about laws, causation and explanation, many of which differ radically from one another.

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.

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.