It's always too early to quit.
Things do not happen. Things are made to happen.
What you do today can improve all your tomorrows.
Go for it now. The future is promised to no one.
If you're going through hell, keep going.
Expect problems and eat them for breakfast.
By failing to prepare, you are preparing to fail.
Problems are not stop signs, they are guidelines.
You never know what motivates you.
If you've got a talent, protect it.
I love the wry motto of the Paleontological Society, meant both literally and figuratively, for hammers are the main tool of our trade: Frango ut patefaciam - I break in order to reveal.