Prof. Mario Livio takes the long view on science. In his newest book, Brilliant Blunders, he points out some of the mistakes made by some icons of science -- Einstein and Pauling among them. More importantly, he insists that researchers must be free to make mistakes.
Livio recently gave us a taste of his subject matter in a talk at the Weizmann Institute (in English):
http://www.youtube.com/watch?v=sYaMlTn275A