Life shrinks or expands in proportion to one's courage.

Have no fear of perfection - you'll never reach it.

A beautiful thing never gives so much pain as does failing to hear and see it.

Science is the most reliable guide for civilization, for life, for success in the world. Searching a guide other than the science is meaning carelessness, ignorance and heresy.

There is no worse bitterness than to reach the end of your life and realized you have not lived.

The desire to fly is an idea handed down to us by our ancestors who... looked enviously on the birds soaring freely through space... on the infinite highway of the air

The nicest thing for me is sleep, then at least I can dream.

We must be willing to fail and to appreciate the truth that often 'Life is not a problem to be solved, but a mystery to be lived.'

Hard work, disciplined habits, modesty in living, contentment and cheerfulness.

If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is.

Life is too short for long-term grudges.

The more you live in the present moment, the more the fear of death disappears.

We were all at once terribly alone; and alone we must see it through.

No one has ever become poor by giving.

In three words I can sum up everything I've learned about life: it goes on.

The more I see, the less I know for sure.

It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.

Life would be tragic if it weren't funny.

I'm never going to be disabled. I'm sick of being so healthy.

Our life is frittered away by detail. Simplify, simplify.

If it is worth doing, it is worth overdoing.