Natural selection has reconstructed our back and lower limbs to the degree that our upright posture is pushing the engineering envelope of what is possible to fashion from our knuckle-walking ape ancestors. Most of us do fine, but at the margins there is an irreducible price of back, hip, and knee problems that some must pay for our distinguished carriage. We don’t think of this as a genetic problem because the genes are healthy and “trying as hard as they can.” Perhaps there are a limited number of “weak” combinations of genes that result in increased vulnerability for these orthopedic problems. Conceivably, some day we might be able to define these weak permutations of normal genes and somehow shore them up. But we are a long way from that.
Mental illness can be viewed in this same manner. Nature has pushed the neurological envelope of evolving regulatory mechanisms in our brain to maintain a dynamic balance between the two motivational systems (called minds) that evolved during our six-million-year evolution.
The defining human adaptation for most of the millions of years of our tribe’s evolution has been the collective capacity to engage in teamwork. Then our own species evolved a passion for what psychiatrists call narcissism and biblical texts refer to as vanity. Appended upon the foundation of our ancient mentality evolved for the coordination of divided labor, each individual evolved a powerful ambition to seek personal happiness by eliciting social esteem (👍). Accordingly, the major psychiatric disorders are the price extracted from our species for the miraculous benefits wrought by the collaboration between our two differently motivated minds—such as reflective self-awareness and the vibrant organism of our language within which we dwell. We might say that those who develop back and lower limb injury pay the price for our stately posture, and, furthermore, the mentally ill should be honored for paying the price for our extraordinary mental capacities.