All the way back, I thought about the fact that I would be held responsible for what was said in that lecture, even though I never heard it. Thereafter, I was always in my seat when Milton Friedman walked in to give his lecture.
On a term paper, I wrote that either (a) this would happen or (b) that would happen. Professor Friedman wrote in the margin: "Or (c) your analysis is wrong."
"Where was my analysis wrong?" I asked him.
"I didn't say your analysis was wrong," he replied. "I just wanted you to keep that possibility in mind."
Milton Friedman