I don't know about that. Individual actors may have long memories, but financial markets as a whole often have the collective memory of a goldfish. During the height of the bubble, there are always people who are proclaiming, "No, this time its different," and "We learned our lesson from last time." And they're right! The actors in the market did learn their lesson from last time. It's just that they make entirely new mistakes that lead to the same end result.