When action is needed, optimism, even of the mildly delusional variety, may be a good thing.

Unfortunately, skill in evaluating the business prospects of a firm is not sufficient for successful stock trading, where the key question is whether the information about the firm is already incorporated in the price of the stock. Traders apparently lackthe skill to answer this crucial question, but they appear to be ignorant of their ignorance.

Below an income of ... $60,000 a year, people are unhappy, and they get progressively unhappier the poorer they get. Above that, we get an absolutely flat line. ... Money does not buy you experiential happiness, but lack of money certainly buys you misery.

Although professionals are able to extract a considerable amount of wealth from amateurs, few stock pickers, if any, have the skill needed to beat the market consistently, year after year.

If you can't take the time for a vacation right now, or even a night out with friends, put something on the calendar - even if it's a month or a year down the road. Then whenever you need a boost of happiness, remind yourself about it.

The brains of humans contain a mechanism that is designed to give priority to bad news.

The premise of this book is that it is easier to recognize other people's mistakes than your own.