Dan Klein has posted an interesting comparison of Adam Smith and Bryan Caplan on the notion of surprise.
On a related note, next month, we at Mercatus will celebrate Dan's new book, Knowledge and Coordination with a book discussion featuring Deirdre McCloskey. Also listen to Dan's EconTalk podcast on the book here.
As an aside, one of my favorite memories from numerous conversations with Vernon Smith was after 9/11 him explaining the difficulty in putting such events into the normal search theoretic framework. As he put it, imagine a giant bowl filled with white and black ping-pont balls, and you know the number of white balls and the number of black balls and you can thus determine the probability of choosing one or the other, but what do you say when you reach into the bowl and you pull out a green ball?
It seems that Smith understood Smith!