Abstract

I defend the idea that the fact that no system is entirely isolated can be used to explain the successful use of the microcanonical distribution in statistical mechanics. The argument turns on claims about what is needed for an adequate explanation of this fact: I argue in particular that various competing explanations do not meet reasonable conditions of adequacy, and that the most striking lacuna in Interventionism – its failure to explain the ‘arrow of time’ – is no real defect.