Edward MacKinnon

The revolt against logical positivism within the philosophy of science has now lasted long enough to produce something of a counter-revolution. As the more strident charges (positivistic analyses misrepresent the most fundamental features of the scientific enterprise and have contributed little or nothing to its clarification) and counter-charges (any attempt to induce a philosophy of science from studies in the history of science rests on a massive genetic fallacy) gradually subside, critical interest is focussing on the presuppositions that guide and structure various interpretations of science. Here epistemological positions, often implicitly assumed, play a pivotal role. In the present article we shall try to make different positions and presuppositions explicit by examining some current developments in the philosophy of science. This examination will be focused on, though not limited to, three recent books by I. Schefller, S. Körner, and E. Harris.

Rom Harré's proposed Copernican Revolution in the philosophy of science is a very ambitious undertaking. It challenges established views, proposes a radically new model for scientific explanation, and forces a rethinking of the foundations of the field. In his treatment of the natural sciences, Harré rejects all deductivist accounts of scientific explanation basically on the grounds that such accounts seriously distort the methods of explanation actually operative in science. In the social sciences Harré, in collaboration with Secord, rejects mechanistic, positivistic, and behavioristic accounts of human behavior [5]. In place of these discarded interpretations he substitutes a new realism which stresses the role that models play in supplying accounts of observed patterns of phenomena in terms of the things and processes whose interactions are responsible for the manifest phenomena. This revolution, if successfully carried out, would indeed be a valuable contribution to the philosophy of science.

The idea that science aspires to and routinely achieves truths about the world has been challenged in recent writings. Rather than beginning with a theory of scientific development, or of scientific explanation, we begin with a consideration of truth claims in ordinary discourse, particularly with Davidson's truth-functional semantics. Next we consider the way in which some framework features of ordinary language discourse are extended to and modified in scientific discourse. Two areas are treated in more detail: quantum theory, and the peculiar problem of semantic entailment it involves; and quantum field theory. These supply a basis for criticizing some historicist and logicist treatments of the truth of scientific claims

The consistent histories reformulation of quantum mechanics was developed by Robert Griffiths, given a formal logical systematization by Roland Omn\`{e}s, and under the label `decoherent histories', was independently developed by Murray Gell-Mann and James Hartle and extended to quantum cosmology. Criticisms of CH involve issues of meaning, truth, objectivity, and coherence, a mixture of philosophy and physics. We will briefly consider the original formulation of CH and some basic objections. The reply to these objections, like the objections themselves, involves a mixture of physics and philosophy. These replies support an evaluation of the CH formulation as a replacement for the measurement, or orthodox, interpretation.

Niels Bohr began his career with an attempt to give a correct descriptive account of the motion of electrons. When forced to abandon this interpretation, he adopted, but soon rejected, a hypothetical-deductive account. In his development of an interpretation for the new quantum theory Bohr began to concentrate on the way language functions to make descriptions possible. His later work on this problem and on the role of concepts in the foundations of science led him to anticipate some of the basic ideas developed in Wittgenstein's Investigations. Bohr eventually saw his own analysis of the conditions of the possibility of unambiguous communication as the basis for making explicit the unity implicit in science

An epistemological interpretation of quantum mechanics hinges on the claim that the distinctive features of quantum mechanics can be derived from some distinctive features of an observational basis. Old and new variations of this theme are listed. The program has a limited success in non-relativistic quantum mechanics. The crucial issue is how far it can be extended to quantum field theory without introducing significant ontological postulates. A C*-formulation covers algebraic quantum field theory, but not the standard model. Julian Schwinger’s anabatic methodology extended a strict measurement-based formulation of quantum mechanics through field theory. His extension also excluded the quark hypothesis and the standard model. Quarks and local gauge invariance are postulates that go beyond the limits of an epistemological interpretation of quantum mechanics. The ontological significance ascribed to these advances depends on the role accorded ontology.

Philosophical interpretations of theories generally presuppose that a theory can be presented as a consistent mathematical formulation that is interpreted through models. Algebraic quantum field theory (AQFT) can fit this interpretative model. However, standard Lagrangian quantum field theory (LQFT), as well as quantum electrodynamics and nuclear physics, resists recasting along such formal lines. The difference has a distinct bearing on ontological issues. AQFT does not treat particle interactions or the standard model. This paper develops a framework and methodology for interpreting such informal theories as LQFT and the standard model. We begin by summarizing two minimal epistemological interpretation of non-relativistic quantum mechanics (NRQM): Bohrian semantics, which focuses on communicables; and quantum information theory, which focuses on the algebra of local observables. Schwinger's development of quantum field theory supplies a unique path from NRQM to QFT, where each step is conceptually anchored in local measurements. LQFT and the standard model rely on postulates that go beyond the limits set by AQFT and Schwinger's anabatic methodology. The particle ontology of the standard model is clarified by regarding the standard model as an informal modular theory with a limited range of validity.

In the course of his long development, Kant's concept of matter changed somewhat, while his concept of scientific explanation changed considerably. Both developments achieved a coherent integration in Kant's Metaphysical Foundations of Natural Science. Using this developmental background, the present paper argues that the Foundations should be interpreted as an attempted rational reconstruction of the mechanics of Newton and Euler. Kant attempted to do this by constructing a concept of matter that would confer a Leibnizian intelligibility on Newtonian mechanics, and also accord with Kant's theories on the nature of concepts and their role in scientific explanation.