"The extraordinary diversity of form and face that characterizes human beings has, over and over, been a source of wonder and delight. Pliny the Elder in his Natural History remarked that, although the human countenance was made up of only "ten parts or a little more," people were so fashioned that "among many thousands no two exist who cannot be distinguished." Nor is an individual person constant throughout life. From birth to death each one of us is in a perpetual state of flux in all our physical and psychic forms? The most dramatic and notorious attempts at explanation have been those simplistic theories that we know as genetic determinism and behaviorism. For the behaviorist, psychic differences are simply the learned responses to repeated stimuli. But the truth is more complicated and less dramatic. An understanding of human physical and psychic variation requires a synthesis of molecular biology, genetics, development, physiology, psychology, sociology, anthropology, political economy, and history. It seemed to me, however, that we do know enough about genetics and development to discredit the naive determinism that has so often passed for science and to provide a hint of the real complexity behind human variation. At the moment, too little is known of the development of mind and body to make a definitive explanation, but there is no reason to suppose we will not eventually understand human diversity fully. As the apostle Paul wrote to the Corinthians,"For now we see through a glass darkly; but then face to face: now I know in part; but then I shall know even as I am known."
-Human Diversity
by Richard Lewontin
pg.ix
