Who said “The successful revolutionary is a statesman, the unsuccessful one a criminal.”?

“Revolutions never go backward.”

“The worst of revolutions is a restoration.”

“Revolution is a trivial shift in the emphasis of suffering.”

“Those who make peaceful revolution impossible will make violent revolution inevitable.”

“Plots, true or false, are necessary things, to raise up commonwealths, and ruin kings.”

“Man's biological weakness is the condition of human culture.”

“Only the person who has faith in himself is able to be faithful to others.”

“Love is the only sane and satisfactory answer to the problem of human existence.”

“Man is the only animal for whom his own existence is a problem which he has to solve.”

“To die is poignantly bitter, but the idea of having to die without having lived is unbearable.”

“Immature love says: ''I love you because I need you.'' Mature love says: ''I need you because I love you.''”