Professor Neil Levy

© 2016 John wiley & sons, inc. All rights reserved. Most of the philosophers engaged in the free will debate accept some kind of naturalism constraint. In this chapter, I distinguish three different kinds of naturalism. Strong naturalists hold that philosophical theorizing should be actually guided by current science, whereas weak naturalists avoid postulating any entities or processes that conflict with science (but may take bets on how science will evolve). Mid-strength naturalism is agnostic about how future science will evolve, but is not actually guided by the science. I argue that though compatibilism tends to fare better on this scale when we consider its relationship to physics, consideration of neuroscience and psychology complicates the picture: major compatibilists engage in as much speculation and scientifically unmotivated postulation of entities and processes as major libertarians. I end by asking whether philosophers engaged in this debate ought to accept that the stronger a view's naturalist credentials, the better warranted it is.