The most malignant consequence of the exceptional human brain is the evil of which it is capable. Human ingenuity led to the development of weapons of individual killing (guns), large-scale murder (machine guns), and massive destruction (nuclear weapons). And because aggression and warfare are an inherent part of human nature, the most potent predator for a human is another human. The history of humans is riddled with conflict and death on a large scale. Ironically, many wars were instigated by various religious groups around the world, who developed intense hostility towards one another.
There are other downsides to the advanced human brain. It can channel its talents and skills into unimaginably wicked and depraved behaviors, such as premeditated and well-planned murder, slavery, cults, child abuse, domestic abuse, pornography, fascism, dictatorships, and political corruption. Astonishingly, the same brain that can be loving, kind, friendly, and empathetic can suddenly become hateful, vengeful, cruel, vile, sinister, vicious, diabolical, and capable of unimaginable violence and atrocities. The advanced human brain definitely has a very dark side.
Finally, unlike other members of the animal kingdom, the human brain generates its virtual counterpart: the highly complex human mind, which is prone to various maladies, labeled as “psychiatric disorders.” No other animal species develops delusions, hallucinations, thought disorders, melancholia, mania, obsessive-compulsive disorder, generalized anxiety, panic attacks, posttraumatic stress disorder, psychopathy, narcissistic and borderline personality disorders, alcohol addiction, and drug abuse. Homo sapiens are the only species whose members decide to end their own life in large numbers. About 25% of human minds are afflicted with one or more of those psychiatric ailments.1,2 The redeeming grace of the large human brain is that it led to the development of pharmacologic and somatic treatments for most of them, including psychotherapy, which is a uniquely human treatment strategy that can mend many psychiatric disorders.
Evolution may not realize what it hath wrought when it evolved the dramatically expanded human brain, with its extraordinary cognition. This awe-inspiring “biological computer” can be creative and adaptive, with superlative survival abilities, but it can also degenerate and become nefarious, villainous, murderous, and even demonic. The human brain has essentially brought evolution to a screeching halt and may at some point end up destroying Earth and all of its Homo sapien inhabitants, who may foolishly use their weapons of mass destruction. The historic achievement of evolution has become the ultimate example of “the law of unintended consequences.”