Pains occupy a distinct and vital place in the philosophy of mind for several reasons. One is that pains seem to collapse the appearance/reality distinction. If an object appears to you to be red it might not be so in reality, but if you seem to yourself to be in pain you must be so: there can be no case here of seeming at all. At the same time, one cannot feel another person’s pain, but only infer it from their behavior and their reports of it.

— Wikipedia on Private language argument

2013.03.31 Sunday ACHK