“Feeling insignificant because the universe is large has exactly the same logic as feeling inadequate for not being a cow.”

“Like every other destruction of optimism, whether in a whole civilisation or in a single individual, these must have been unspeakable catastrophes for those who had dared to expect progress. But we should feel more than sympathy for those people. We should take it personally. For if any of those earlier experiments in optimism had succeeded, our species would be exploring the stars by now, and you and I would be immortal.”

“The whole [scientific] process resembles biological evolution. A problem is like an ecological niche, and a theory is like a gene or a species which is being tested for viability in that niche.”

“You know you're doing what you love when Sunday nights feel the same as Friday nights....”

“The hardest part of writing is the same as doing your homework...it's staying seated in your chair.”

“When you see someone who has turned his passion into a profit, ask yourself, ‘Why not me?”

“Feelings are not supposed to be logical. Dangerous is the man who has rationalized his emotions.”