Science and technology have been making steady progress for the past 400 years, but comparatively little progress has been made in human ethical behaviour. Modern scientific work on the structure of the human brain suggests that evolution has shaped a brain of flawed design, capable of great rational power but incapable of adequately controlling base instincts. This idea has been expanded on by Arthur Koestler in The Ghost in the Machine,1967.
Copernicus started the modern scientific revolution in 1543 when he proposed that the sun and not the earth resides at the centre of our solar system. Since then science has discovered a huge amount about how the natural world works.
We now know how the world began about 15 billion years ago in a massive explosion, how the stars and planets formed, how the 92 natural elements were made and how our solar system was formed five billion years ago. We know how life began on earth almost four billion years ago as a simple single form and how, from that simple form, all the myriad forms of life that now inhabit the earth evolved. We also know much more.
Science-based technology has allowed us to land on the moon, to take pictures of the farthest reaches of the universe, to communicate instantly with each other around the globe, to live in warmth and light in the middle of winter, to enjoy plentiful variety of food at all times, to travel easily around the globe, to distract ourselves with all forms of entertainment - the list is endless.
On the other hand, much of the political and social history of the world, from the earliest times up to the present day, has been fraught with trouble, privation, war and paranoia. Anthropologists have shown that from the earliest times ritual human sacrifice was a ubiquitous practice across all cultures. Human sacrifice was conducted in order to placate gods conceived of in nightmares.
In the middle ages we burned witches and slaughtered each other in religious wars. We tortured and burned heretics in the inquisition. In the 20th century we killed Jews and others on an industrial scale under the Third Reich. We witnessed horrors under Stalin and Pol Pot and, in some places today, we still sentence people to death by stoning. And now, for the first time, we developed weapons so powerful that their use in a global war could wipe out human civilisation.
Humans are unusual but not unique in the animal kingdom in their relative lack of instinctive safeguards against killing members of their own species. While it is true that members of other animal groups do fight amongst themselves, these conflicts are usually settled without the infliction of lethal injury.
Why are humans so prone to violence and paranoia? Some scientists, notably the Canadian neurologist Paul MacLean, have suggested that at least part of the answer lies in the manner in which the human brain evolved.
Humans are descended from an evolutionary line of predecessors and throughout its evolution three components became superimposed in the human brain. The evolutionary sequence was reptile, lower mammal, and higher mammal, of which humans are a particular example. So humans can be viewed as having three brains - the oldest is basically reptilian, the second inherited from the lower mammal, and the third is a late mammalian development that makes us human.
We can think of the reptilian and lower mammal brain as the "old brain" as opposed to the neocortex, the "new brain", which is the "human" part. The old brain is largely responsible for self preservation and controls autonomic functions, instinct, biological drives and emotions. We have inherited it relatively unchanged.
The neocortex of the hominid expanded in the last million years at an explosive and unprecedented speed. The reasoning powers of man are located in the cortex but the explosive development of this capacity never properly integrated with the old brain on which it was superimposed. The new rational brain does not exert clear-cut control over the passions and drives of the old brain. So is there any hope for us then if the basic structure and organisation of our brains makes it so difficult for us to consistently behave rationally? The answer is yes, but we must work hard at it.
Firstly, an understanding of why our basic drives, lusts and emotions are so intrusive in our lives makes it easier to go about controlling them. Secondly, the effort that must be made to control our basic drives can be eased by the certain knowledge that control of these drives leads to contentment and success, whereas, their unmanaged victory leads to unhappiness and failure.
Many people experience an awful emptiness in the modern developed world and try to fill it with alcohol and other drugs and the uninhibited pursuit of sexual gratification. This only exacerbates the problem and leads many to despair.
The only way out of this pit is through the exercise of the new brain. People need a sensible philosophy of life that explains why we are here and where we are going. Scientific understanding is an important part of any reasonable philosophy, and I believe another vital element is the cultivation of a spiritual dimension. Development of both these areas will go a long way towards damping down excessive intrusions of the old brain.
William Reville is associate professor of biochemistry and director of microscopy at UCC