Some quotes I liked from: http://www.newyorker.com/reporting/2009/10/05/091005fa_fact_cassidy
For more see: http://delicious.com/mbgmbg/clust_bridge_keynes_quotes
Millennium Bridge
It initially closed in '00 then reopened: "The real problem was that the designers of the bridge... had not taken into account how the footway would react to all the pedestrians walking on it."
Keynes view on our "third degree" guesses
Keynes’s jaundiced view of finance reflected his own experience as an investor .... He compared investing to newspaper competitions in which “the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average preferences of the competitors as a whole; so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view.... It is not a case of choosing those which, to the best of one’s judgment, are really the prettiest, nor even those which average opinion genuinely thinks the prettiest... We have reached the third degree, where we devote our intelligences to anticipating what average opinion expects the average opinion to be. And there are some, I believe, who practice the fourth, fifth and higher degrees.”
Points on the Prisoner's dilemma
Because financial markets consist of individuals who react to what others are doing, the theories of free-market economics are often less illuminating than the Prisoner’s Dilemma, an analysis of strategic behavior that game theorists associated with the RAND Corporation developed during the early nineteen-fifties....
Imagine that you and another armed man have been arrested and charged with jointly carrying out a robbery. The two of you are being held and questioned separately, with no means of communicating. You know that, if you both confess, each of you will get ten years in jail, whereas if you both deny the crime you will be charged only with the lesser offense of gun possession, which carries a sentence of just three years in jail. The best scenario for you is if you confess and your partner doesn’t: you’ll be rewarded for your betrayal by being released, and he’ll get a sentence of fifteen years. The worst scenario, accordingly, is if you keep quiet and he confesses.
What should you do? The optimal joint result would require the two of you to keep quiet, so that you both got a light sentence, amounting to a combined six years of jail time. Any other strategy means more collective jail time. But you know that you’re risking the maximum penalty if you keep quiet, because your partner could seize a chance for freedom and betray you. And you know that your partner is bound to be making the same calculation. Hence, the rational strategy, for both of you, is to confess, and serve ten years in jail. In the language of game theory, confessing is a “dominant strategy,” even though it leads to a disastrous outcome.
