Never complain and never explain.
You never know what motivates you.
The dog that trots about finds a bone.
Be thine own palace, or the world's thy jail.
Either you run the day or the day runs you.
Without hard work, nothing grows but weeds.
Know or listen to those who know.
Who seeks shall find.
The most effective way to do it, is to do it.
By failing to prepare, you are preparing to fail.
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.