This is a lesson to not assume you're good at investing if otherwise intelligent. The Intelligent Investor, by Graham, brings up the archetypical example of a

This is a lesson to not assume you're good at investing if otherwise intelligent. The Intelligent Investor, by Graham, brings up the archetypical example of a doctor/dentist and his financial misadventures. His (or her) disadvantage is that they're obviously intelligent which pushes them to be overconfident in a field in which they have zero experience. Overconfidence breeds poor risk management and eventual trouble.