Why be an option/futures/day trader when it is zero-sum?
getp: The irrationality you are referring to is called the self-serving bias (SSB). I wrote a thesis on overconfidence for my master in behavioral economics, and the two are related. SSB is a well-documented bias. For instance, 90% of American drivers think they are in the top 50%. It's hard for people to fully appreciate this fact. Allow me to illustrate. Do you still consider yourself, even after reading this statistic, to be in the bottom 50% of drivers? If so, then you're a minority, my friend ;-) (10%, to be exact)