Theories pass. The frog remains.
Truth is always served by great minds, even if they fight it.
Take heed of critics even when they are not fair; resist them even when they are.
The biologist passes. The frog stays the same.
Never feel remorse for what you have thought about your wife; she has thought much worse things about you.
Somebody told me I should put a pebble in my mouth to cure my stuttering. Well, I tried it, and during a scene I swallowed the pebble. That was the end of that.