Lawrence Sklar

Those who think of some aspects of the world as "physically necessary" usually think of this kind of necessity as being confined to the general law of nature, initial conditions being "contingent." Tachyon theory and general relativity provide independent but related reasons for thinking that some initial states are, however, "impossible." And statistical mechanics seems to lead us to conclude that some initial conditions are, if not impossible, "highly improbable." We are then, led from these aspects of physics to wonder if initial conditions are always "freely specifiable" and in the domain of physical contingency.

Despite over one-hundred years of effort, the origin of temporal asymmetry in the physical world still eludes us. While much has been learned about the role played by fundamental instabilities in microdynamics, by the imperfect isolation of systems and by cosmological facts in the origin of the behavior described by kinetic theory and thermodynamics, important puzzles still remain which continue to make the origins of asymmetric thermal behavior out of dynamically time symmetric underlying laws mysterious to us.

It has been argued, most trenchantly by Nancy Cartwright, that the diversity of the concepts and regularities we actually use to describe nature and predict and explain its behavior leaves us with no reason to believe that our foundational physical theories actually "apply" outside of delicately contrived systems within the laboratory. This paper argues that, diversity of method notwithstanding, there is indeed good reason to think that the foundational laws of physics are universal in their scope.

In this paper, I want to focus attention on ways in which the role of idealization in science has been rather neglected by standard methodology, and suggest that this distinct role for idealization is the truly important role it plays in science. Further, I suggest that there are a number of important cases in theoretical science where the issue of idealization is not the issue of misrepresentation in some sense. Rather, the question is which of several alternative idealizations correctly represents the fundamental causalstructure of the world, and which idealizations, consequently, are appropriate for the scientific account of the world that is correct in its basic notion of what is an appropriate explanatory format for dealing with the physical phenomena in question. My argument is that the issues of idealization are important for methodology not primarily for the reasons that have so far exercised most philosophers of science who have worried about idealization in science.