If you can dream it, you can do it.
It's always too early to quit.
If you think you can do it, you can.
Leap, and the net will appear.
Never complain and never explain.
To be a good loser is to learn how to win.
Without hard work, nothing grows but weeds.
I can, therefore I am.
Problems are not stop signs, they are guidelines.
After a storm comes a calm.
The frontiers of knowledge in the various fields of our subject are expanding at such a rate that, work as hard as one can, one finds oneself further and further away from an understanding of the whole.