Wanting vs. liking

http://lesswrong.com/lw/1lb/are_wireheads_happy/

I think this is really central to our understanding of human nature. Scientists are now starting to distinguish pleasure from wanting. This really rings true to me: we often seek things we don't particularly like, and fail to seek things we do like.

When this author talks about wireheads, he's referring to people who have had an electrode placed in their brains, directly stimulating a particular brain center. That sort of thing offers tremendous insight into how we operate.