Shortly after his arrival in Berlin, the famous creator of the quantum hypothesis, Planck, forgot in which audience he should be reading a lecture, and went to the office to find out about it.
“Tell me, please,” he asked an elderly man who was in the office, “which classroom is Professor Planck lecturing today?”
The old man kicked him on his shoulder. “Don’t go there, young man,” he said. “You’re still too young to understand the lectures of our wise Professor Planck.”