There are two kinds of future concern: desire and fear. They together create a perfect hell.

The Ancient Sage

The habit of forever looking backward is fatal to efficiency just as is the habit of looking forward too much. Today is the day. Live the day and have done with it. Fling your best into it, then you have nothing to regret, and there is no need of anticipating tomorrow.

O. S. Marden

Never regret anything because at one time it was exactly what you wanted.

Marilyn Monroe

An education isn't how much you have committed to memory, or even how much you know. It's being able to differentiate between what you know and what you don't.

Anatole France

If the problem can be solved why worry? If the problem cannot be solved then worrying will do you no good.

Shantideva

At twenty years of age the will reigns; at thirty, the wit; and at forty, the judgment.

Benjamin Franklin