When I was younger, I knew everything and ended up making a lot of mistakes because of it.
Older friends of mine would look at me and smile. They didn't dare attempt to teach me anything because "he who knows everything can't be thought."
Now that I'm a bit older, and see a little bit more clearly the error in my ways, I can do little else than smile at the younger generation of geniuses.
Today I understand what my old friends were smiling about... I wonder what else they're smiling at me about?