Abstract

I claim in this article that if my experience is such that it seems to me that there is an external object before me, then I have reason to believe that there is an external object before me. The sceptic argues that since my having the experience is compatible both with there being and with there not being an external object before me, I have no reason to believe that the former possibility obtains and not the latter. I respond that the sceptic has ignored a relevant difference between the two possibilities: I can make sense of the former possibility but not of the latter. I examine two broad categories of sceptical possibilities (dreams and hallucinations), explain why I cannot make sense of them, and explain why my inability to make sense of them gives me reason to believe they do not obtain.