Decoherence: the view from the history and philosophy of science.

We present a brief history of decoherence, from its roots in the foundations of classical statistical mechanics, to the current spin bath models in condensed matter physics. We then analyse the philosophical importance of decoherence in three different foundational problems, and find that its role in their solutions is less than that commonly believed. What makes decoherence more philosophically interesting, we argue, are the methodological issues it draws attention to, and the question of the universality of quantum mechanics.