Tim O'Reilly on differentiating knowledge types:

Planck knowledge and chauffeur knowledge:
After winning the Nobel prize, Max Planck went around Germany giving talks. His chauffeur heard the talk so many times that he had it by heart, and so one time, he asked Max Planck if he could give the address. Planck agreed, they changed places, and the lecture came off famously. But then came the Q&A, with the very first question being one that the chauffeur had no hope of answering. The chauffeur replied: "I'm surprised to hear such an elementary question on high energy physics here in Munich. It's so simple, I'll let my chauffeur answer it."

Posted by esinclai at June 25, 2005 10:19 AM |