The instinctive need to be the member of a closely knit group fighting for common ideals may grow so strong that it becomes inessential what these id….

All scientific knowledge to which man owes his role as master of the world arose from playful activities..

Historians will have to face the fact that natural selection determined the evolution of cultures in the same manner as it did that of species..

Scientific truth is universal, because it is only discovered by the human brain and not made by it, as art is..

The attitude of the true scientist towards the real limits of human understanding was unforgettably impressed on me in early youth by the obviously u….

We do not take humor seriously enough..

All the advantages that man has gained from his ever-deepening understanding of the natural world that surrounds him, his technological, chemical and….

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

The distance at which all shooting weapons take effect screens the killer against the stimulus sensation which would otherwise activate his killing i….

All too willingly man sees himself as the centre of the universe, as something not belonging to the rest of nature but standing apart as a different ….

It ought to be realized by all dog owners that obesity shortens a dog's life quite considerably, a life which is much too short anyhow..

The fidelity of a dog is a precious gift demanding no less binding moral responsibilities than the friendship of a human being..

I would rather have a Scot come from Scotland togovern the people of this kingdom well and justly, than that you should govern them ill in the sight ….

Every mutation through a new combination of genetic factors that provides the organism with a new opportunity for coming to terms with the conditions….

Few animals display their mood via facial expressions as distinctly as cats..

Man appears to be the missing link between anthropoid apes and human beings..

I see the creative accomplishments of which highly gifted humans are capable as special cases of the universal creative process, that game played by ….

The truth about an animal is far more exciting and altogether more beautiful than all the myths woven about it..

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….

In nature we find not only that which is expedient, but also everything which is not so inexpedient as to endanger the existence of the species..

Just thinking that my dog loves me more than I love him, I feel shame..