Having worked in IT for so long and grappled with Murphy's Law for so long, I'm finding that I need to correct for an extreme negative bias in my thinking. So I'm now reading things like "Success Through a Positive Mental Attitude" by Clement Stone, and other things in that vein. That leads me to ask: how many of you have profited by reading those kinds of books? If not, do you think they may actually be harmful to a trader? I can see where you would need to be positive and optimistic if you want to keep a business going, but being unduly optimistic about specific positions you take might actually hurt you. Seems like a contradictory way of thinking.