Here's a passage from Durant (the Durants) I used to use in my philosophy course. It always made for a snappy, not to say instructively acrimonius discussion. This was back in the day, of course, when actual discussion. was still possible, and legal:
History is a fragment of biology: the life of man is a portion of the vicissitudes of organisms on land and sea. Sometimes, wandering alone in the woods on a summer day, we hear or see the movement of a hundred species of flying, leaping, creeping, crawling, burrowing things. The startled animals scurry away at our coming; the birds scatter; the fish disperse in the brook. Suddenly we perceive to what a perilous minority we belong on this impartial planet, and for a moment we feel, as these varied denizens clearly do, that we are passing interlopers in their natural habitat. Then all the chronicles and achievements of man fall humbly into the history and perspective of polymorphous life; all our economic competition, our strife for mates, our hunger and love and grief and war, are akin to the seeking, mating, striving, and suffering that hide under these fallen trees or leaves, or in the waters, or on the boughs. Therefore the laws of biology are the fundamental lessons of history. We are subject to the processes and trials of evolution, to the struggle for existence and the survival of the fittest to survive. If some of us seem to escape the strife or the trials it is because our group protects us; but that group itself must meet the tests of survival. So the first biological lesson of history is that life is competition. Competition is not only the life of trade, it is the trade of life peaceful when food abounds, violent when the mouths outrun the food. Animals eat one another without qualm; civilized men consume one another by due process of law. Co-operation is real, and increases with social development, but mostly because it is a tool and form of competition; we co-operate in our group-our family, community, club, church, party, "race," or nation-in order to strengthen our group in its competition with other groups. Competing groups have the qualities of competing individuals: acquisitiveness, pugnacity, partisanship, pride. Our states, being ourselves multiplied, are what we are; they write our natures in bolder type, and do our good and evil on an elephantine scale. We are acquisitive, greedy, and pugnacious because our blood remembers millenniums through which our forebears had to chase and fight and kill in order to survive, and had to eat to their gastric capacity for fear they should not soon capture another feast. War is a nation's way of eating. It promotes co-operation because it is the ultimate form of competition. Until our states become members of a large and effectively protective group they will continue to act like individuals and families in the hunting stage. The second biological lesson of history is that life is selection. In the competition for food or mates or power some organisms succeed and some fail. In the struggle for existence some individuals are better equipped than others to meet the tests of survival. Since Nature (here meaning total reality and its processes) has not read very carefully the American Declaration of Independence or the French Revolutionary Declaration of the Rights of Man, we are all born unfree and unequal: subject to our physical and psychological heredity, and to the customs and traditions of our group; diversely endowed in health and strength, in mental capacity and qualities of character. Nature loves difference as the necessary material of selection and evolution; identical twins differ in a hundred ways, and no two peas are alike. Inequality is not only natural and inborn, it grows with the complexity of civilization. Hereditary inequalities breed social and artificial inequalities; every invention or discovery is made or seized by the exceptional individual, and makes the strong stronger, the weak relatively weaker, than before. Economic development specializes functions, differentiates abilities, and makes men unequally valuable to their group. If we knew our fellow men thoroughly we could select thirty per cent of them whose combined ability would equal that of all the rest. Life and history do precisely that, with a sublime injustice reminiscent of Calvin's God. Nature smiles at the union of freedom and equality in our utopias. For freedom and equality are sworn and everlasting enemies, and when one prevails the other dies. Leave men free, and their natural inequalities will multiply almost geometrically, as in England and America in the nineteenth century under laissez-faire. To check the growth of inequality, liberty must be sacrificed, as in Russia after 1917. Even when repressed, inequality grows; only the man who is below the average in economic ability desires equality; those who are conscious of superior ability desire freedom; and in the end superior ability has its way. Utopias of equality are biologically doomed, and the best that the amiable philosopher can hope for is an approximate equality of legal justice and educational opportunity. A society in which all potential abilities are allowed to develop and function will have a survival advantage in the competition of groups. This competition becomes more severe as the destruction of distance intensifies the confrontation of states.