"Investors with large amounts of capital obtained from a windfall or from inheritance are much more likely to suffer large losses because they are less likely to truly feel the pain of losing money. Because they did not go through the arduous process of earning it themselves, they view their capital as 'found money.' In comparison, the long-term trader is able to feel the pain of losing and, accordingly, takes the necessary steps to mitigate his losses and to reduce the likelihood of incurring similar losses in the future. Financial survival in the markets is very difficult without the capacity to feel pain, for pain and fear can function as a protective covering, which the psychiatrists claim allows the organism the opportunity to recover and return to a neutral state."
The Mind of the Markets, by F. J. Chu.