Work ethic is important, because, unlike intelligence, athleticism, or charisma, or any natural attribute, it’s a choice.

Nothing is impossible if you want it badly enough. Impossible = I'm possible.

A hero is no braver than an ordinary man, but he is braver five minutes longer.

It is never too late to turn an unproductive day into a productive one.

The journey of a thousand miles begins with one step. 

The greatest enemy to human potential is your comfort zone

There are no bad mistakes in maths, only discoveries.

You cannot escape the responsibility of tomorrow by evading it today

The temptation to quit will be the greatest when you are about to succeed

Dreams don't work unless you do.

Hard work always pays off - it is not a question of if you will get there, but WHEN you will get there

Everything you want is on the other side of fear

Whenever you find yourself doubting how far you can go, just remember how far you have come.

You can have results or excuses, not both

1.00³⁶⁵=1 and 1.01³⁶⁵=37.7. Doing nothing at all versus small steps at a time.