The appeal of the cat lies in the very fact that she has formed no close bond with [man], that she has the uncompromising independence of a tiger or a leopard while she is hunting in his stables and barns: that she still remains mysterious and remote when she is rubbing herself gently against the legs of her mistress or purring contentedly in front of the fire.

Hatred of humanity and love of animals make a very bad combination.

Evil, by definition, is that which endangers the good, and the good is that which we perceive as a value.

Visualize yourself confronted with the task of killing, one after the other, a cabbage, a fly, a fish, a lizard, a guinea pig, a cat, a dog, a monkey and a baby chimpanzee. In the unlikely case that you should experience no greater inhibitions in killing the chimpanzee than in destroying the cabbage or the fly, my advice to you is to commit suicide at your earliest possible convenience, because you are a weird monstrosity and a public danger.

Every mutation through a new combination of genetic factors that provides the organism with a new opportunity for coming to terms with the conditions of its environment signifies no more and no less than that new information about this environment has got into that organic system. Adaptation is essentially a cognitive process.

I have found the missing link between the higher ape and civilized man; it is we.

Humor and knowledge are the two great hopes of our culture.