"When the facts change, I change my mind. What do you do, sir?" said John Maynard Keynes [1], supposedly. Bayes Theorem is the simple rule for how to update one's beliefs as new information arrives, that is, "when the facts change" about a situation. People are mocked when they modify their lifestyle abruptly after a major event — a heart attack, a lucky lottery drawing, a religious conversion, a divorce, the loss of a job. "Nobody on their deathbed ever wished they had spent more time at the office," etc.

But perhaps they're just making a proper (Bayesian) adjustment? A sudden shift in one's life expectancy should result in a sudden change in behavior; likewise for alteration of financial resources, or values, or the range of available choices in other dimensions.

(cf. Expert Political Judgment, ...) - ^z - 2011-06-21