Abstract
The Assimilation Argument purports to show that libertarians cannot plausibly distinguish supposed exercises of free will from random outcomes that nobody would count as exercises of free will. If this argument is sound, libertarians should either abandon their position or else concede that free will is a mystery. Drawing on a parallel with the Manipulation Argument against compatibilism, Christopher Franklin has recently contended that the Assimilation Argument is unsound. Here I defend the Assimilation Argument and the Rollback Argument, a second challenge to libertarianism that Franklin rejects. My aim in doing so is to underscore the force of these challenges, and thereby to resist what appears to be an emerging trend in the literature. By not coming to grips with the kind of power that libertarians must secure, many writers have recently downplayed or dismissed the pressing worry for libertarianism