In the central cases of physical pain, then, it appears that at least part of what is bad about our condition is the way it makes us feel. Here there seem to be no problems with a purely mental state account, no counterpart to the experience machine that could bring us to think that we are being deceived by mere appearances. [...] If I am suffering physical pain then I can be quite wrong about the organic cause of my affliction, or even about whether it has one, without that error diminishing in the slightest either the reality of my pain or its impact on the quality of my life.