Quality is not an act, it is a habit.
The wise does at once what the fool does at last.
Who seeks shall find.
I can, therefore I am.
Begin to be now what you will be hereafter.
If you can dream it, you can do it.
It's always too early to quit.
What you do today can improve all your tomorrows.
Always desire to learn something useful.
You never know what motivates you.
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.