I have no fault to find with those who teach geometry. That science is the only one which has not produced sects; it is founded on analysis and on synthesis and on the calculus; it does not occupy itself with the probable truth; moreover it has the same method in every country.

If soldiers were to begin to think, not one of them would remain in the army.

Theologians are all alike, of whatever religion or country they may be; their aim is always to wield despotic authority over men's consciences; they therefore persecute all of us who have the temerity to tell the truth.

Great things are achieved only when we take great risks.

It is impossible to imitate Voltaire without being Voltaire.

Everybody is using coffee. If possible, this must be prevented. My people must drink beer.

Do not neglect the principles of foresight and know that often, puffed up with success, armies have lost the fruit of their heroism through a feeling of false security.