Quote by Jean d'Alembert
"The mind that is too rigid to change is already dead."
More from Jean d'Alembert
"Doubt is an uncomfortable condition, but certainty is a ridiculous one."
"The greatest mathematicians, like the greatest poets, are men of imagination."
"I believe in God, but I do not believe that God has any of the properties which theologians ascribe to him."
"The true method of knowledge is experiment."