Roberta Millstein
California Sate University, Hayward

Abstract
Evolutionary theory is probabilistic at several levels: at the level of genetic mutation, at the level of the survival and reproductive success of individual organisms, and at the level of the division and extinction of species. This uncontroversial claim raises a number of contentious issues. For example, is the evolutionary process (as opposed to the theory) indeterministic, or is it deterministic? Philosophers of biology have taken different sides on this issue, and elsewhere, I have argued that we have insufficient reason to favor determinism or indeterminism, and that therefore, we should remain agnostic on this question. However, a further issue remains: how should we understand the probabilities used in evolutionary theory? Are they merely a convenient way to camouflage a multitude of unknown causes, or are they in some sense objective (and not simply a product of our ignorance)? I will take steps towards answering these questions, focusing on the probabilistic nature of random drift and natural selection from a position of agnosticism on the determinism/indeterminism question.

Biography
Roberta Millstein is Assistant Professor of Philosophy in the Department of Philosophy at California State University, Hayward. She received the Ph.D. in Philosophy, with a minor in the History of Science and Technology, from the University of Minnesota. Millstein's research focuses on the role of chance in evolutionary theory. However, she is also interested in using the philosophy of biology to illuminate issues in the philosophy of science (probability, causality, determinism, and explanation in particular), environmental ethics, and biomedical ethics. Millstein's work has appeared in Philosophy of Science and Biology and Philosophy. She has also written the "Evolution" chapter for the forthcoming Blackwell Guide to the Philosophy of Science.

If you have questions, contact the CHPS Office at (301) 405-5691 or by e-mail at hp26@umail.umd.edu. Information about colloquia is also available on-line hrough the CHPSCOL LISTSERV and on the WWW at http://carnap.umd.edu/chps.

Fall 2001