He who wishes to be rich in a day will be hanged in a year.

Human subtlety will never devise an invention more beautiful, more simple or more direct than does nature because in her inventions nothing is lacking, and nothing is superfluous.

I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.

I have offended God and mankind because my work didn't reach the quality it should have.

I love those who can smile in trouble, who can gather strength from distress, and grow brave by reflection. 'Tis the business of little minds to shrink, but they whose heart is firm, and whose conscience approves their conduct, will pursue their principles unto death.

In rivers, the water that you touch is the last of what has passed and the first of that which comes; so with present time.

He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.

It had long since come to my attention that people of accomplishment rarely sat back and let things happen to them. They went out and happened to things.

Beyond a doubt truth bears the same relation to falsehood as light to darkness.

It's easier to resist at the beginning than at the end.

A well-spent day brings happy sleep.

Iron rusts from disuse; water loses its purity from stagnation... even so does inaction sap the vigor of the mind.

He who is fixed to a star does not change his mind.

For once you have tasted flight you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return.

Experience does not err. Only your judgments err by expecting from her what is not in her power.