“All the arguments to prove man's superiority cannot shatter this hard fact: in suffering the animals are our equals.”

“The fact that man knows right from wrong proves his intellectual superiority to the other creatures; but the fact that he can do wrong proves his moral inferiority to any creatures that cannot.”

“As a philosopher, if I were speaking to a purely philosophic audience I should say that I ought to describe myself as an Agnostic, because I do not think that there is a conclusive argument by which one can prove that there is not a God. On the other hand, if I am to convey the right impression to the ordinary man in the street I think that I ought to say that I am an Atheist, because, when I say that I cannot prove that there is not a God, I ought to add equally that I cannot prove that there are not the Homeric gods.”

“...the student of prehistoric man...cannot reject [the Castenedolo skull] as false without doing injury to his sense of truth, and he cannot accept it as fact without shattering his accepted beliefs.”

“Once made equal to man, woman becomes his superior.”

“All animals are equal, but some animals are more equal than others.”