mechanics and classical mechanics as competing theories. In the perspective of LCP the appraisal is quite different. The extension of classical concept to quantum experiments brings out the limited applicability of these concepts and of the language in which they function. One cannot simultaneously use complementary concepts in describing a system without generating contradictions. A choice must be made and implemented through the way the experiment is set up and interpreted. The necessity of such a choice brings to the forefront the role of the subject in the functioning of LCP. The alleged subjectivity of quantum mechanics is actually a realization of the nature and limits of classical physics.
From an internal perspective the objectivity of physics is not problematic. The practice of physics entails acceptance of a large, but no so amorphous, collection of claims as true. Here ‘true’ must be interpreted as really true, or true of reality, not merely accepted as true. This does not presuppose an independent access to objective reality that supplies a basis for appraising the truth of physical claims. It simply presupposes that on such issues physics is the ultimate court of appeals. When the truth of particular claims are doubted or denied the only meaningful recourse is to do better physics, not to abandon physics. It is not possible to doubt the truth of all physical claims and continue to do physics. The claim they are true of the world involves the same circularity that Davidson and Gadamer indicated for ordinary language. The world of physics is the world as give to us through physics.
2.5 An External View of Physics
In addition to using physics to understand reality one can make physis itself an object of critical analysis. This is something done in different ways by sociologists, historians, philosophers, and reflective physicists. Here I will only consider two philosophical approaches and only consider them from a sharply limited perspective. Each supports the conclusion that the type of claims just considered may seem objective when appraised on the basis of uncritical internal standards, but cannot be considered objective in a larger more critical context. We will label these interpretative perspectives The primacy of theories and The deconstruction of physics.
The way LCP has so far been used as a basis for interpretation reflects a purely functional view of mathematical formulations and theories. This is surely inadequate. Mathematical formulas and theories do play a functional role in experimental research, in the dialectical interplay between experimenters, and in much of the work done by theorists. Yet the study of equations in isolation from experimental research has repeatedly led to unanticipated consequences. One can argue that theories encapsulate the greatest advances of physics and should supply the basis for interpretations of physics. Before exploring such a claim we should attempt to situate the type of theories we are talking about.
We begin with Einstein’s distinction between principle theories, such as thermodynamics and special relativity, which supply constraints that processes must observe; and constructive theories, which attempt to build a picture of complex phenomena out of the materials of a very simple formal scheme. Many theories only have limited scope, e.g., theories of ferromagnetism, superconductivity, Bose-Einstein gas, neutron stars. The theories that provoke the ontological controversies pertinent to the issues treated here are generally constructive theories of broad scope that are not reducible to more basic theories. Contemporary debates about scientific realism are