Most of the vices and mortal sins condemned today correspond to inclinations that were purely adaptive or at least harmless in primitive man.

I consider early childhood events as most essential to a man's scientific and philosophical development.

I have found the missing link between the higher ape and civilized man: It is we.

I grew up in the large house and the larger garden of my parents in Altenberg. They were supremely tolerant of my inordinate love for animals.

We had better dispense with the personification of evil, because it leads, all too easily, to the most dangerous kind of war: religious war.

I believe that present day civilized man suffers from insufficient discharge of his aggressive drive.