My briefest ever definition of science fiction is 'Hubris clobbered by Nemesis.'
Science fiction is for real, space opera is for fun.
The day of the android has dawned.
Keep violence in the mind Where it belongs (Barefoot in the Head)
It is at night... that the mind is most clear, that we are most able to hold all our life in the palm of our skull.
Civilization is the distance man has placed between himself and his excreta.