Well as long as we are having a psychological discussion... Agree that realists can be optimists, and I think I fit in that category - looks as if you do too. But there's also a class of people that I would call persistently optimistic, and they often deny others' reality. Against all odds and in any situation, they are attached to their vision, and deeply believe it is attainable. Once they commit to something, Katy bar the door... it's going to happen! These people, thank goodness, are not always realistic. They sometimes disregard common sense, balance sheets, history... because they believe so deeply. Remember the tablet computer that failed at least 10 times in the market until the iPad? Who was persistently optimistic about that? I only use that example because it's common knowledge -- I know many people personally (well... I knew Jobs too) who fit this model in less public, recognizable roles. They can be infuriating to work with and be friends with, but I admire their vision, commitment, and single-mindedness.