The Evolutionary Origin of Moral Instincts
- Aparthib

...Moral instinct  itself is rooted in the laws of nature (Physics) via the working of the brain. Morality is latent in the laws of nature. It finds expression through the process of evolution...


For the newer members below are the links to the previous eight writeup in this series:
  1. Science, Objectivity &; Postmodernism
  2. Science vs. Mysticism &; Philosophy
  3. Science, Logic, Faith, Beauty.. etc
  4. Science, Miracles &; the Paranormal
  5. On the Nature vs. Nurture Debate
  6. A Scientific View of Life Death Immortality:
  7. Brain and Religion
  8. Freewill vs. Predestination


In two of my previous posts I have dwelt on two aspects of morality viz (1) The question of whether morality is defined by religion and (2) If morality is purely subjective. I wish to supplement the above two essays with a discussion on the evolutionary basis of moral instincts, which I had alluded to in those earlier essays but did not discuss it greater detail.


The view that morality is something not due to a pure physical cause-effect but due to some special human quality, not subject to the unconscious scientific laws, has been ingrained among many, even among many scientifically literate liberals and humanists. Morality, like human emotions of love and affection seems to them to be too lofty, too "divine" to be relegated to the mechanistic explanations of physical laws. To them it is almost an insult to the human spirit to discuss them in physical terms. Humans are not machines they contend. As I mentioned in my previous companion essay "Soul, Brain and the Laws of Physics", that such view really amounts to positing a human soul, to which these lofty values of morality and emotions are attributed to. I also pointed out that positing a soul leads to all sorts of contradictions and paradoxes. The fact is that the overwhelming evidence of science indeed points to a purely physical basis of the origin of morality and human emotions. The physical laws (Laws of Physics) acting in the background directs the forces of evolution, which ultimately leads to complex evolved organs to solve problems in order to survive and propagate the gene successfully under selection pressure. One of the most important organ evolved is the human brain (mind). Human brain is the paragon of a complex design from simple steps acting over a long (millions of years) time scale. There is nothing in human nature that is not rooted in human brain. It is important to realize that human brain is not crafted anew for each individual, rather it has imprinted in it an evolutionary history of all that has happened in the evolutionary past, (through what is known as the epigenetic rule) preserving all the knowledge of the successful survival strategies, in a cumulative fashion. The emergence of morality is intimately related to the evolution of the human brain in constant interplay with the environment and with other brains. What we call culture is not created by some entity external to human brains. Culture IS a creation (as another evolutionary strategy for maximizing evolutionary fitness of human species) of the human brain. Many view moral instincts as the product of culture, as if culture is something distinct from human brain. But as I argued culture itself is a creation of evolutionary forces and thus physical laws (acting on the brain and environment). As philosopher Donald Cameron says in the summary of his main arguments of his book "The Purpose of Life":
"There is a popular fallacy that a further source of values for humans is an emergent property of culture. (Do not be deceived by the word "emergent": it just means things are complex and no one knows what is going on.) These values are supposed to act over and above the values derived from our genetic evolution, largely replacing them. This idea cannot be justified. It may be regarded as one more example of our vanity, in trying to believe that we are different from the beasts in kind, not only in degree. We can understand how value information could be programmed into our brains by natural selection, but how could further values be invented by information which we pass from one brain to another? Of course we culturally transmit our values to each other, but these values originate in the brains, not in the transmission process."


So moral instinct (which also assigns values, i.e the "ought" to thoughts, emotions and actions,) itself is rooted in the laws of nature (Physics) via the working of the brain. Morality is latent in the laws of nature. It finds expression through the process of evolution. It seems almost common sensical/logical that if human brain and thus human mind is a product of evolution and subject to the laws of nature, then moral instinct, which is a product of human mind (over generations) must also be the product of evolution and thus ultimately the laws of Physics. Culture is the proximate cause, but the laws of physics the ultimate cause.


In the words of sociobiologist Edward O.Wilson : "ought is the product of a material process. The solution points the way to an objective grasp of the origin of ethics" (From his paper "The Biological Basis of Morality")

How does evolution give rise to moral instinct? Evolutionary psychology provides the plausible scenario. Again in his paper "The Biological Basis of Morality" Edward O. Wilson illustrates it this way:

"Suppose that human propensities to cooperate or defect are heritable: some people are innately more cooperative, others less so. In this respect moral aptitude would simply be like almost all other mental traits studied to date. Among traits with documented heritability, those closest to moral aptitude are empathy with the distress of others and certain processes of attachment between infants and their caregivers. To the hereditability of moral aptitude add the abundant evidence of history that cooperative individuals generally survive longer and leave more offspring. Following that reasoning, in the course of evolutionary history genes predisposing people toward cooperative behavior would have come to predominate in the human population as a whole.

Such a process repeated through thousands of generations inevitably gave rise to moral sentiments. With the exception of psychopaths (if any truly exist), every person vividly experiences these instincts variously as conscience, self- respect, remorse, empathy, shame, humility, and moral outrage. They bias cultural evolution toward the conventions that express the universal moral codes of honor, patriotism, altruism, justice, compassion, mercy, and redemption."

More insight into the evolution of morality is provided by Game Theory. A classic example being the Prisoner's Dilemma. Let us describe this dilemma concisely:

Two prisoners, A and B, are being held in separate cells with no means of communication. The prosecutor offers each of them a deal. He also disclosed to each that the deal was also made to the other. The deal he offered is this:

a) If one guy confesses that both of them committed the crime and the other guy denies it, then he will go free and the other guy will be sentenced to 5 years.

b) If you both deny the crime, then both will be sentenced to 2 years.

c) If both confess to the crime, then both will be sentenced to 4 years.

If someone confesses then he either goes free (0 years) or gets 4 years. If he doesn't confess then he gets either 2 years (if both denies) or 5 years (If the other guy confesses) . So from each one's individual perspective the payoff is better if he confesses rather than denies (0 or 4 years is better than 2 or 5 years). So if both are logical and selfish they both should confess. The result is that both will fare worse than if they had BOTH denied, contradicting their individual logic! So if such prisoner's dilemma is repeated many times and if the two prisoners can communicate then even though they may initially both confess, by trial and error they will learn to cooperate instinctively and will evolve an ethical code "thou shalt not confess". That's why criminal gang members do not tell on each other, Evolution works that way. Over millions of years, evolution has instilled an ethical sense starting from the tribal group of early people to the modern people. The sense of morality is not implanted in human mind from some transcendental realm, it is a hardwired instinct. Our "feeling" of conscience is an emergent property of the brain reflecting that hardwired instinct. And ethics is not a unique trait of human species. A primitive form of code of ethics is seen among wolf pack as well, where pecking order, punishment and rewards are observed. Of course, human brain having possessed the emergent property of self-consciousness has the most advanced and complex form of code of ethics.

Evolutionary biologists use the term adaptive for those instincts that favor the survival and propagation of genes, and those that hinder anti-adaptive. Moral instincts are the adaptive traits of evolution and are favored overwhelmingly over anti-adaptive traits. Evolutionary psychology not only explains the origin of moral instincts but also the origin of the "immoral" (can be neutral or anti-adaptive in the evolutionary sense) instincts as well. In Bible we see Jobs imploring God to explain why he is subject to so much evil and injustice? God did not provide any satisfactory answer. But now Evolutionary biology is offering a plausible explanation. In fact so much of evidence and insight has been gained in recent' times that a plethora of scholarly scientific books and articles have been written on the evolutionary origin of vice and virtue, on evolutionary ethics. So why do we have evil? If morality is selected by natural selection then why do humans have immoral instincts as well? It is best understood by analogy. One cardinal point is that evolutionary force, like humans are lazy, they try to achieve its goal (survival, propagation of genes) by the easiest/ simplest possible way. Let us take an analogy. Let us say the US military wants to kill the insurgents in an area. To kill only the insurgents it requires a lot of work to gather the information about the location and also a lot of planning and discipline to selectively target the bombing. It is much easier to bomb an extended area killing the maximum number of civilians, that is guaranteed to kill the intended insurgents but at the price of killing a large number of innocent civilians, as an overkill/collateral damage. Another nice analogy is provided by Gould and Lewtonin by the spandrel in arches. A spandrel is the roughly triangular region on either side of the top of an arch, a necessary but unintended byproduct of architectural design. An arch cannot be built without the spandrel. Immorality is the collateral damage of evolutionary strategies, so to speak. Evil is a necessary but unintended consequence of evolution.


As Michael Shermer in his book "How we believe" nicely illustrates that human brain has evolved to:
  1. Believe in false
  2. Disbelieve the truth
  3. Believe in the truth
  4. Disbelieve the false
Among the above only (3) and (4) are evolutionarily adaptive. But to ensure that (3) and (4) can be true evolution, being lazy enables brain for all of the four possibilities. (1) and (2) are like the spandrel of an arch, collateral damage as in the carpet bombing. Also among the traits originating from (1) and (2) only those survive that are evolutionarily neutral (i.e neither clearly adaptive nor clearly anti-adaptive).

Among the collateral damage an important unintended instinct is rape. The reason the practice of rape still survives is that it is not anti-adaptive. The forces of evolution does not have a moral sense like we do. It does anything to help maximize gene propagation. And rape does not disfavour that. Not only that it may have served as one means of propgation in past. That is the theme of the book "The Natural History of Rape" by evolutionary biologist Thornbull and anthropologist Palmer. Their central argument is that "rape is a genetically developed strategy sustained over generations of human life because it is a kind of sexual selection--a successful reproductive strategy"

Thornbull and Palmer has been predictably misunderstood as condoning rape. They are not. It would be a naturalistic fallacy to promote a "IS" into an "OUGHT". They were simply explaining the evolutionary origin of rape. But they were not justifying or condoning it. Description is not prescription. Explanation is not exculpation. Matt Ridley, another biologist also says "Rape was evolutionarily adaptive" in his book "The Origins of Virtue." as quoted in p-45 of "Sexing the Brain" by neuropsychologist Lesley Rogers.

The presence of evil is an inevitable result of the physical laws acting to sustain equilibrium or stability and thus avoid extinction of a species. As I mentioned earlier evil is a necessary unintended byproduct of evolution. Lying can be seen to be another such necessary but unintended trait. As physicist Heinz Pagels nicely illustrates in his book "The Dreams of Reason", page 330:

"The new sciences of complexity and the perspectives on the world offered by computer modelling may teach us things that we did not realize about the values we hold. Science cannot resolve moral conflicts, but it can help to more accurately frame the debates about those conflicts. Take for example, the act of lying. We hold the telling of truths as a value; we are not supposed to lie. Yet if everyone told the truth all the time so that one could have complete trust in what one is told, then the advantage that would accrue to a single liar in society would be immense. This is not a stable social situation. On the other hand, in a society of individuals in which everyone lied all the time, society would be unworkable. The equlibrium state seems to be the one in which people tell the truth most of the time but occasionally lie, which is how the world really seems to be. In a sense, then, it is the liars among (and within) us that keep us both honest and on our guard. This kind of scientific analysis of lying can help us understand why we do it."
Just as evolution does not favor that all be truthful, it also does not favor all be liars. In favors some liars among a majority of truthful. Game theory confirms all this fundamental fact of nature. Basically it confirms the old cliché that evil is necessary so good can exist. But this time it is given a mathematical justification. An utopian world of no evil is theoretically impossible in a species made of carbon based life form as we know it.

Published at Mukto-mona 


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