Quote from The Conquest of Happiness

 In the chapter entitled "Envy", Russell compares humans to apes.

"Through the movies they think they know how the rich live, through the newspapers they know much of the wickedness of foreign nations, through propaganda they know of the nefarious practices of all whose skin has a pigmentation different from their own. Yellows hate whites, whites hate blacks, and so on. All this hatred, you may say, is stirred up by propaganda, but this is a somewhat shallow explanation. Why is propaganda so much more successful when it stirs up hatred than when it tries to stir up friendly feeling? The reason is clearly that the human heart as modern civilization has made it is more prone to hatred than to friendship. And it is prone to hatred because it is dissatisfied, because it feels deeply, perhaps even unconsciously, that is has somehow missed the meaning of life, that perhaps others, but not we ourselves, have secured the good things which nature offers for man's enjoyment. The positive sum of pleasures in a modern man's life is undoubtedly greater than was to be found in more primitive communities, but the consciousness of what might be has increased even more. Whenever you happen to take your children to the Zoo you may observe in the eyes of the apes, when they are not performing gymnastic feats or cracking nuts, a strange strained sadness. One can almost imagine that they feel they ought to become men but cannot discover the secret of how to do it. On the road of evolution they have lost their way, their cousins marched on, and they were left behind. Something of the same strain and anguish seems to have entered the soul of civilized man. He knows there is something better than himself almost within his grasp, yet he does not know where to seek it or how to find it. In despair he rages against his fellow man, who is equally lost and equally unhappy. We have reached a stage in evolution which is not the final stage. We must pass through it quickly, for if we do not, most of us will perish by the way and the others will be lost in a forest of doubt and fear. Envy therefore, evil as it is and terrible as are its effects, is not wholly of the devil. It is in part the expression of a heroic pain, the pain of those who walk through the night; blindly, perhaps to a better resting place, perhaps only to death and destruction. To find the right road out of this despair, civilized man must enlarge his heart as he has enlarged his mind. He must learn to transcend self, and in so doing to acquire the freedom of the Universe."