 Pains are said to be private to their owners in the strong sense that no one else can epistemically access one’s pain in the way one has access to one’s own pain, namely by feeling it and coming to know one is feeling it on that basis. This sharply contrasts with the public nature of objects of standard perception, that is, perception of one’s immediate extramental environment including one’s body. Let’s call this exteroception, to contrast with introspection which is access to one’s intra-mental activity. So, for instance, the very same apple I see on the table can be seen by others in possibly the exact same way I see it, so is not private in this sense.