A theory of laws of nature, dispositions, and chances

What are the fundamental properties of the world? What is chance? What are the laws of nature? These questions may seem isolated, but in my dissertation, A Theory of Laws, Dispositions, and Chances, I show how they are connected by developing a new account that unifies traditionally disparate elements. I defend the anti-Humean claim that there are some fundamental, modal features in the world—such as chance and dispositional properties. But, I also defend the Humean claim that the laws of nature merely describe the world, rather than govern it. According to my view, which I call the Propensity Best System Account (PBSA), some of the fundamental properties are dispositional—these properties are called potencies if they are deterministic, and propensities if they are chancy. And the laws of nature systematize all of the possible distributions of those properties. The PBSA provides a new way of interpreting a probability measure over all of the possible initial states of the universe: as a fundamental chance that grounds all subsequent chances. I argue that the PBSA accords well with scientific practice. Laws that systematize the distribution of properties suit the importance scientists place on simplicity and informativeness when they describe the regularities in the world. Potencies and propensities, which are necessarily connected to the behavior of the entities that instantiate them, are faithful to the scientific principle that the best way to learn about a system is by studying its characteristic behavior in different (stimulus) conditions. The PBSA avoids many of the serious objections that face traditional, best system accounts of the laws of nature and chance. For instance, the PBSA yields the right results for the laws of nature in both simple worlds and in improbable worlds. I argue that the PBSA is a promising theory of chance whether the dynamical laws of nature are deterministic or probabilistic and it can be formulated for consistency with classical mechanics or for consistency with quantum mechanics.Ph. D.Includes bibliographical referencesby Heather Demares