Problems are not stop signs, they are guidelines.
What you do today can improve all your tomorrows.
To know oneself, one should assert oneself.
It's always too early to quit.
After a storm comes a calm.
Things do not happen. Things are made to happen.
The most effective way to do it, is to do it.
The wise does at once what the fool does at last.
The dog that trots about finds a bone.
I can, therefore I am.
I wrote somewhere during the Cold War that I sometimes wish the Iron Curtain were much taller than it is, so that you could see whether the development of science with no communication was parallel on the two sides. In this case it certainly wasn't.