Precis of Laws and Symmetry

Abstract

Laws and Symmetry has three main objectives. The first is to show the failure of philosophical accounts of laws of nature. The second is to undercut the epistemological principles at work in arguments for the reality of laws of nature. The third objective, nearest to my heart, is to be constructive as well, and to contribute to an epistemology and a philosophy of science antithetical to such metaphysical notions as laws of nature. Part One, in which the first objective is pursued, was the main subject of discussion in the symposium to follow. In this Synopsis, therefore, I shall concentrate on that. In my view, as presented in Chapter 1, the concept of a law of nature is an anachronism, its proper life belonging to the 17th and 18th Centuries. Laws of nature played an important role in the philosophical-scientific thinking of Descartes and Newton, and functioned for them as a central clue to the structure of science. At the same time, two developments threatened the status of law. One was the empiricist critique of necessity and causality, notions closely allied to that of law. The other was that science was rapidly gaining autonomy not only from theology but from all of philosophy, and was exploiting concepts and methods foreign to metaphysics. Pre-eminent here is the birth of the symmetry argument. (Discussion of this subject is begun in Chapter 1 and continued in Chapters 10, 11 and 12.) Modern physics argues from symmetry and continuity-not from universality or necessity, natural kinds or essences, contingency or accident. The concept of a law of nature is a vestigial concept in contemporary science. Chapter 2 collects the cluster of criteria for what laws must be and do, which are honored in the literature to some degree or other. We can divide the criteria to be met by any philosophical account of laws roughly into major requirements and secondary ones. The major criteria concern what I call the problems of inference and identification. The accounts must show that there is a valid inference from what laws there are to what regularities there are in the world. The account must also identify the relevant aspects of the world that constitute or give rise to its laws, if any. Typically these two tasks lead