There are things I can't force. I must adjust. There are times when the greatest change needed is a change of my viewpoint.

— Denis Diderot

There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.

— Denis Diderot

There is only one passion, the passion for happiness.

— Denis Diderot

We swallow greedily any lie that flatters us, but we sip only little by little at a truth we find bitter.

— Denis Diderot

When science, art, literature, and philosophy are simply the manifestation of personality they are on a level where glorious and dazzling achievements are possible, which can make a man's name live for thousands of years.

— Denis Diderot

When superstition is allowed to perform the task of old age in dulling the human temperament, we can say goodbye to all excellence in poetry, in painting, and in music.

— Denis Diderot

Whether God exists or does not exist, He has come to rank among the most sublime and useless truths.

— Denis Diderot

You have to make it happen.

— Denis Diderot

You live as if you were destined to live forever, no thought of your frailty ever enters your head, of how much time has already gone by you take no heed. You squander time as if you drew from a full and abundant supply, so all the while that day which you bestow on some person or thing is perhaps your last. Furthermore, you have all the fears of mortals and all the desires of immortals… What foolish forgetfulness of mortality to defer wise resolutions to the fiftieth or sixtieth year, and to intend to begin life at a point to which few have attained.

— Denis Diderot

You risk just as much in being credulous as in being suspicious.

— Denis Diderot