Nature is perfectly impartial. Brain has no sex!
Every new truth begins in a shocking heresy.
It is useless to deny that, unless one has a genius for imparting knowledge, teaching is a drudgery.
As soon as you feel too old to do a thing, do it.
Nothing may be more selfish than remorse.
I'm not to blame for an old body, but I would be to blame for an old soul. An old soul is a shameful thing.