The Implications of Evolution
Published on Darwin Day (February 12, 2006)
A lot of the debate on evolution is focused on whether evolution has occurred or not. Defenders of evolution take great pains to offer the evidence and logic in support of evolution and to refute the position of creationists. But even many of the subscribers to the notion of evolution do not grasp the full implications of the fact of evolution. That will be my focus in this essay. The FACT of evolution is beyond debate, the detailed mechanism is not. My essay assumes the fact of evolution as a given. The simple fact of evolution has profound implications that can have a tremendous impact on the way one looks at life and it's various aspects including morality, values, social customs and human behaviour in general. When I refer to evolution, it will mean all the detailed insights obtained through the research in the fields of evolutionary biology/psychology.
The lesson of evolution is that all life forms including humans arose out of an incremental evolution from a primitive life form over billions of years by a purely natural process and that the primitive life form itself arose out of an incremental evolution of complex molecules in the prebiotic atmospheres of early earth through purely chemical processes, called chemical evolution. Since the laws of physics is the ultimate governing principle behind all natural processes, the conclusion we can draw is that evolution, and thus all life forms are results of the laws of physics. One is forced to conclude this by pure logic and evidence. Denying this simple fact is tantamount to positing a "vital or divine" force driving life forms, humans in particular. The temptation to deny this fact is strong, specially because of the consciousness of human mind, which is intriguing and difficult to explain precisely by natural laws. Even many freethinkers who claim to believe in evolution unwittingly deny this fact when they refer to "human spirit", and passionately champion many of the "humanistic ideals", saying that humans are not machines, that love, morality and "human values" are not subject to mechanical laws etc. We have seen in Mukto-Mona many freethinkers making the point that morality is not subject to science or that science cannot be used to formulate morality. While it is true that science cannot be used to formulate morality, but it is also not true that anything else can be used to formulate morality either. So that point cannot be used to propose one's own favored moral views to counter the moral views putatively based on science that happen to contradict their favored views. But one thing that can be stated with certainty is that the notion of morality, as a product of evolution, is certainly a consequence of scientific laws (physics). So even though humans cannot use science to formulate morality, morality itself is a product of scientific laws.
The cold, stark fact is that since all life forms are results of pure natural processes dictated by the laws of physics, hence all aspects of life, including consciousness, love, morality are necessary (evolutionary) consequences of the same natural laws. This simple, yet profound fact is hard to accept even by many secular humanists, let alone theists. To say that any aspect of life is not subject to the laws of physics is to say that that aspect is subject to an (ill-defined) "divine force", "soul" etc. Pure and simple. There is no in between. It is one of those either or cases. Any attempt to have it both ways, just because it sounds politically correct or appeals to one's taste will be intellectually disingenuous. Many nontheists argue that biology (thus evolution) is not subject to the laws of physics. That is a subtle manifestation of yet another attempt to retain some semblance of a divine factor (by implication, by denying the naturalness of biology). This position is taken by philosopher Nancy Cartwright. In the book : "The Large, the Small and the Human Mind" (based on a series of three lectures in Cambridge's Tanner Series on Human Values), she challenges the assertion by Stephen Hawking that chemistry is a consequence of physics, and biology is a consequence of chemistry and thus human mind is a consequence of the laws of physics. Of course professional biologist/chemists (Richard Dawkins, Peter Medawar and Peter Atkins for example) do not have this illusion and are fully aware of this epistemological chain from physics to biology. Suffice it to say that this epistemological chain from physics to biology should be fairly obvious to anyone with a moderate understanding of physics and biology and capable of critical thinking. One simple observation can help: Most chemistry books devote their first few chapters on the physics of atoms and molecules, and most biology books devote their first few chapters on organic chemistry
The skeptical view questioning this epistemological chain is only expressed by non-scientists. Coincidence? Not at all. Let me belabor this point a bit more and cite some quotes from scientists on this physics-->biology chain. While it is true that any view cannot be justified by solely resorting to an argument from authority, nevertheless this citation helps to reinforce this assertion of the epistemological chain, because there is no similar example of scientists expressing a view contradicting this.
Now let me cite some quotes of various scientists in support of the above epistemological chain. Nobel Laureate Watson of DNA fame said "In the last analysis, there are only atoms. There's just one science, Physics; everything else is social work" in his lecture at the London Institute of Contemporary Arts in 1985. This view is also echoed by Stephen Hawking and Steven Weinberg. Hawking nicely summarizes this view as: Biology->Chemistry-> Physics, in the book "The Large, the Small and the Human Mind". Steven Weinberg says in his book "Facing Up", p-22-3: "No biologist today will be content with an axiom about biological behaviors that could not be imagined to have a more fundamental level. That more fundamental level would have to be the level of Physics and chemistry, and the contingency that the earth is billions of years old". Biologist Richard Dawkins (in "The Blind Watchmaker") states that Physicists have to come into the scene at the end of the long chain of reasoning to explain evolution of life to complete the last but not the least significant step. Molecular Biologist Franklin Harold says in his wonderful book "The Way of the Cell", p-4: "We have ample reason to believe that every biological phenomena, however complex, is ultimately based on chemical and physical interactions among molecules" and reinforces this in his epilog : "The bedrock premise of this book book is that life is a material phenomenon, grounded in chemistry and physics. Physicist Heinz Pagels wrote in his book "The Dreams of Reason", p-49: "Biological systems are extremely complex Quantum mechanical entities functioning according to well-defined rules". Zoologist and award winning science writer Colin Tudge says (Independent on Sunday, Jan 25, 1998): "There are no biological laws, apart from the underlying laws of physics, and technology might anything that does not break these bedrock laws". In the book "Our Living Multiverse: A Book of Genesis in 0+7 Chapters", alternately titled as "Origins of Our Existence : How Life Emerged in the Universe" author Fred Adams (Univ. of Michigan Physics Professor) writes:These same laws of physics instigate the development of life, including complex creatures such as humans, at least under favorable circumstances. (p-191)"We now know that the laws of Physics ultimately determine the behavior of chemical reaction and biological processes." (p-192)The consummate example of emergent behavior is life itself. In simple reactions, biochemical molecules behave according to known chemical pathways. When these molecular systems become sufficiently complex, they act in novel ways. After this emergent level of complexity reaches a critical threshold, the system becomes alive. But the details of this transition remain shrouded in mystery. In spite of this gaping hole in our understanding, however, biological processes are driven by the same laws of physics that describe stars and planets. The concept of vitalism -- the idea that biological laws are independent of physical laws -- has been safely relegated to the trash heap of outdated ideas. (p-193)From Back Flap:With so much talk about the frontier of biology these days, I welcome the occasional reminder that the laws of physics control the formation and evolution of life. - Neil DeGrasse Tyson, Director, Hayden PlanetariumAs a final example renowned biologist Earnst Mayr wrote in his book "The growth of Biological Thoughts ('82): "Every biologist is fully aware of the fact that molecular biology has demonstrated decisively that all processes in living organisms can be explained in terms of Physics and chemistry"(As cited in Weinberg,"Facing Up", p-19)
Let me digress more into this issue as it is vital to the "Darwinian" view of life. By Darwinian I mean the view that life is a product of natural process (i.e processes governed by the laws of physics). It is now understood that the fundamental constituents of matter (electrons, quarks) follow the laws of physics. It is also understood that matter, living or non-living, are composed solely of these fundamental elements. No life forms (dead or alive) has been found to contain any element other than these fundamental elements.
Now if we know that the individual elements obey the laws of physics then it stands to reason that an aggregate of these constituens must also be subject to the laws of physics. If one electron, quark or string obeys the laws of physics then a system of n electrons and quarks (n is very large, for a living object) must also act according to the laws of physics. To say that a human is not just a product of the laws of physics but more, is NOTHING BUT that old vitalism in disguise. There is no third possibility. Either physics or an unknowable entity (God/Soul..) dictates the actions of the system of electrons and quarks called humans. I am not saying that all is known about physics. The knowledge of physics itself is a continually expanding horizon. By Physics in this essay I will mean tht totality of known and yet to be known laws that govern the evolution of the universe. Now let me clarify a VERY important point. Just because life is governed by the laws of Physics, that doesn't mean that every aspect of life can be DERIVED by the laws of physics. Let me illustrate this point with a very simple example. We know particles/objects obey the laws of gravitation. Using the laws of graviation we can precisely predict how a two particle system (like a star with one planet) will move. The orbit can be predicted precisely, or conversely the observed trajectory of two particle system can be explained precisely by the equations of gravity. Now just add one more particle to this system. No one can PRECISELY predict the exact orbit that a three particle system. That is because the laws of gravitation are non-linear. A non-linear equation cannot be solved exactly. So the observed trajectories of the particles in a three particle system cannot be exactly explained/derived by the laws of gravitation. Do we then say that a miracle/divine force is governing the three particle motion? Obviously not. Even though the observed trajectories of the particles cannot be explained/derived by the laws of gravitation, the important fact is that they do not violate the law either. And since there is no evidence that a third unknown force enters into the picture as soon as a third particle is added to a two particle system, thus the fact still remains that the laws of graviation determine the trajectories of three or any number of particles, even though we can only derive the trajectories of only a two particle system. Now extend this argument to humans. A human is enormously complex system of trillions of particles interacting with not just gravitational force but electro-weak and strong forces as well. If we cannot even precisely determine the behaviour of three particle systems, it would be naive to expect to be able to explain the behaviour of a human being in terms of the laws of physics. There is no fundamental difference between living and non-living matter, the difference is due to the complexity and emergent effects. Laws of Physics do control the behaviour of all matter, living, or non-living. No vital prcesses of a living organism, viz. metabolism, reproduction etc, involve any mechanism that violates or does not follow any known laws of Physics, like the law of conservation of energy, law of entropy etc. And since no living object has displayed any property that has violated the known laws of physics, we can draw the conclusion that that any property (including emotions, beliefs etc) of humans are ultimately DUE to the laws of Physics. To deny that will clearly be tantamount to invoking some mysterious force somewhere (Like in some religious texts, a "soul" is said to be implanted into the embryo at some point). In the evolutionary paradigm, life and death of any life forms are different states of matter. No mysterious force enters into a living body and leaves the body after death. Non-living matter (including a corpses) are in thermodynamic equlibrium, living matters are in highly non-equlibrium thermodynamic state. Just as a piece of iron can be in a magnetized state or non-magnetized state with no change in its material composition. Or just as a computer running a program is one state of the computer and a computer shut down is another state of the computer, with nothing entering or leaving the computer. One can say that that a human started and stopped the computer. But that human is also a system governed by the laws of physics and the human+computer system is thus acted on also solely by the laws of physics which cause the human to start and stop the computer (Alternating between two states). EVERY PHENOMENA in universe is coded into the laws of physics. Our entire universe is a system of incredibly large number of systems of particles (of which a human is a subsystem). A human is a very specialized complex system, and the laws of complexity determines its state, including the state of being alive or dead. It is the laws of complexity that give rise to the action of death genes responsible for the natural death of humans.
All this may sound like the much dreaded idea of reductionism, but reductionism or wholism is a term coined by arm chair philosophers, not scientists. There is no *scientfic* concept called reductionism or wholism. Science is about seeking and formulating statements of (tentative) truth about reality based on the best evidence available. The fact that even in physics sometimes the whole is not just the sum of its parts in the sense that the precise motion or properties of an aggregate is not exactly derivable in terms of the properties of the individual constituents, can be labelled wholism, but that labelling does not dismiss the fact that the properties of the whole is still ultimately due to the properties of the fundamental constituents, not something beyond the laws of physics. The motive behind coining those labels is the same, a subtle attempt to retain a semblance of some "divine" factor in life, a refusal to accept that life can be totally a result of natural process. By denying that biology is a consequence of physics, they wish to leave open a divine intervention on biological process (thus life) not explainable by or subject to natural laws.
Now on to the main theme of my essay, which is the implication of this simple, yet profound insight. One immediate implication is the illusion of "I/me/we". When"we" say "we" there is an implied existence of an entity beyond our physical body, acting as a driver/engine of "our" body. "I" will stop quoting "I", "we"... from this point on for simplicity, but I will use these words in the sense of an identifying label. But as it should be clear now that there is nothing external or internal to the physical body dicating the action of human body that is not part of the body itself. In fact consciousness is an emergent property of matter, brain in this case. Emergent properties are manifestations of complexity in chaotic systems, i.e systems that follow non-linear equations and are composed of large number of elements. Such systems exihibit consistent patterns that can be described quantitatively (by the laws of complexity) but because of the inherent non-linearity of the underlying laws of physics, the laws of complexity cannot be derived in terms of the laws of physics exactly. Human brain is the prime example of a complex system. It is not just a random collection of billions of neurons, but an organ that is a result of millions of years of evolution, thus ultimately a product of the laws of physics. And the synaptic connections of the brain in the cerebral cortex is a result of hundreds of thousands of years of evolution. And it is the synaptic connections the brain that endows it with the emergent property called consciousness, unique to each individual because of the uniqueness of the synaptic connections of each human brain. This is what neurologist Joseph Ledoux calls The Synaptic Self. When we refer to I or we, we are really referring to the synapatic connections of the I/we. Our every action and thought (Which defines a person) is ultimately determined by the laws of physics through the medium of the synaptic connections of the brain.
The implication of the above is that there is no intrinsic meaning of the notion of "Free will". Whatever act we commit or whatever we think/believe are the ultimate result of the laws of physics. If we carefully stare at the cliche "Yes, we can do whatever we choose to do, we have free will, humans are not robots, they are thinking, living beings with mind, emotions and sense of right and wrong and ability to choose between them" we will see the fallacy in it. All the "we's in those statements really refer to the person's brain. The free will itself is an outcome of the laws of physics working in the brain. Just because we have an illusory perception of free will, that does not change the fact that every act and thought are ultimately determined by the laws of physics. Yes, humans do have choices available, but which choice will be made in a given situation is ultimetely determined by laws of physics. We may have the illusions that "we" made the choice freely, but as I argued the "we" itself is a system that works according to the laws of physics. There is no player other than the brain and the laws of physics in the matter of choice. A free willed choice is an illusion inside the brain of the human making that choice. There is no will free from the laws of physics. We are truly puppets on a string. The string being the "Laws of Physics", or "string" theory (no pun intended). Some proponents of free will invoke the randomness inherent in in all of nature's processes to justify the existence of free will. That is a flawed position. For one thing randomness is a relative notion. With the entire universe being a large syetem with large number of elements, one part may seem to be random with respect to another part. But the entire universe as a whole is determinsitic, governed by the laws of physics. There is no random act that occurs violating or not required by the laws of physics. The timing of the individual decay of a quantum particle appears random and can only be predicted statistically by Quantum Mechanics, but that does not mean that the decay happened due to some non-physical cause. Randomness is an epistemological notion reflecting limitations in our complete understanding of the underlying reality, not a fundamental notion of physics. Secondly even if the randomness was beyond physics, the free will due to randomness will still be not determined by the brain/body of the person exercizing the free will. The free in that case may be free from physics, but not free from whatever is causing the randomness. So either way the notion of free will dissolves into meaninglessness, because the very notion of free will implies the existence of an independent driving force beyond physics that causes a human to make choices, essentially equivalent to proposing a "soul" hypothesis and the free will is then relegated to the soul of that person.
Another implication of the natural view of life is that morality or ethics are also the result of the laws of physics and thus have no intrinsic meaning. The "should"s or "oughtta"s are instincts instilled into the brain by evolution, and thus by physics. We often hear the cliches "Morality is not subject to scientific laws", as if morality is subject to some "other" laws. This statement is vague in itself. But the simple fact that morality is due to an instinct instilled by evolution immediately makes it clear that the origin of moral instincts is coded into the laws of physics. The causal chain is : Physics-->Evolution-->Brain-->Morality. And it is evolution which instils a "should" in our mind. There is no intrinsic criteria of morality outside and independent of physics. Morality is the overall sense of right and wrong instilled into the brain of human species through evolution. There can be variation in that moral instinct in individual humans within human species, but statistically the morality among the species as a whole is such that it helps to preserve the species. And morality also can change and adapt due to evolutionary pressure. We often hear religious believers justify belief in God by raising the question that without a belief in God how can there be morality, and wouldn't humans and society in general slide into immorality and chaos? The fallacy in this argument is that morality will be there, regardless of religious belief, as morality is a product of evolution. In fact even religious belief itself is one form of evolutionary strategy for survival. Religious morality is rooted in the more fundamental evolutionary instinct of morality, although the religious believers have the illusion that their moral beliefs are due to a belief in God's commandments. The moral instinct, being a product of evolution, is present in theists and atheists alike in varying degrees. The only thing belief in religion adds is a set of ritualistic practices and behaviour peculiar to a religion. There can be individual variations of morality among humans, so there will be instances of individuals with no sense of morality, or different from the average. For many who do not believe in God (in the traditional religious sense) and understand that there is no objective basis of morality, they still feel a strong inherent instinct against committing certain acts. They cannot justify with absolute reason, why they should not commit those acts, but nevertheless cannot commit those act either. Even those who understand that their moral senses are due to evolution, also feel the instinct of right and wrong and act accordingly. It is a curious thing, but there is no contradiction, in fact it is all self-consistent. Again a stark reminder that each human is a system of particles obeying laws of physics, irrespective of their beliefs. Even if for some reasons all humans suddenly turned into atheists, humans species (via the laws of physics) will always find a way to enforce some standards of morality, purely for evolutionary survival. Human species will not allow itslef to self-destruct, physics does not admit of that solution of it's equation, figuratively speaking.
A human is a very special system of particles having a property called consciousness capable of making a human appreciate that they are a system of particles run by the laws of physics. Not every human can realize this capabilty of appreciating this fact however.
Philosophers of science have always been intrigued by this so-called consciousness loop :
Physics-->Evolution-->Consciousness-->(Discovery of) Physics
It is indeed intriguing to realize that this circular chain is due to the laws of physics (that human mind can discover laws of physics is also rooted in physics!). It is all internally self-consistent.
The same is true for instincts of fear/anxiety. They are also hardwired by evolution in the primitive part of the brain. Rationalism, which is a byproduct of the evolution of human brain in the cerebral cortex and has no causal effect on those instincts. So one can be rational and but still have an instinct of fear, like afraid of staying alone in a deserted house, just as one can feel the instinct of morality without believing in God or on any absolute criterian for morality. Fear of the unknown is an evolutionary instinct. So is love, and in fact all emotions. Passionate champions of humans rights can refute religious beliefs and justify a secular approach to morality and human rights, using such expressions as "human spirit is noble" "love is supreme" etc. But at the end these are appeal to emotions, not a cold, hard, logical positions. All that matters is what evolution instills in the brain on the average. Of course evolution itself creates this necessary tension between two opposites. Tension is essential to stability. This fact has been acknowledged by scientists in the light of evolution and a detailed analysis of mathematical modelling of the evolutionary mechanisms. We know by this insight that if each member of human species were completely honest or dishonest, or kind and generous, or extremely violent or malicious that will not be evolutionarily stable and will lead to self destruction of human species. Evolution requires a stable and optimal distribution of evil and good. This is a purely mechanical/ natural consequence of physics. A simple example of that would be the hypothetical situation where there is barely enough food for one to survive and there are two starving good people. They will both die rather than one eating the food and letting the other die. Similarly a society with all liars or all truthful will also lead to an evolutionary instability. The most stable state is some liars but majority truthful in varying degrees. The fact that most people believe lying is wrong, and telling the truth is right, is also a consequence of evolutionary mechanism to create that stable state. Evolution will not allow all humans to become philosophers or religious extremists either. That stabilty requires a statistical variation is one of the most profound insights of evolutionary science. Evolution requires inequality for survival of some. If all are equally strong, they will mutually destroy each other. If all are weak, they also will eventually self-destruct also. A distribution of the strong and the weak is a necessary(evil) so that some may survive. This is the hardest lessons of evolution to assimilate. This fact of evolution, natural selection, was used by some in the past to promote social inequality and eugenics (started with Herbert Spencer in Victorian England). That was a fallacy of promoting an "is to an ought" also known as naturalistic fallacy. The fact is that what is in nature cannot be justified as right or wrong. Nature will be whatever it will be based on physics. The fact that such views of Darwinism didn't hold up only points to the fact that evolution does not favour eugenics, hence such views (called social Darwinism) got weeded out by evolution itself. We have to credit physics for the demise of social Darwinism, if we have to. The lofty talk about triumph of humanity or human spirit etc to explain that is just a metaphor of language.
Humanists can passionately call for an utopian world of humans devoid of any ill feeling, full of love for all. But such utopian state of all ideal humans is not consistent with the laws of evolution i.e physics. But the yearning and passionate struggle to achieve that utopia is not. That urge is part of evolution itself Also just like the instincts of morality and fear, an appreciation that all such yearnings for idealism is produced by evolutionary forces does not result in a loss of that instinctual yearnings. That is the paradox, if you will, of evolution/physics. An understanding/discovery of the laws of physics cannot affect or alter the laws of physics!.
One may get the feeling that all this talk about life and human emotions being nothing but the result of the laws of physics takes away the mystique, the romanticism of human imagination. Nothing is further from the truth. Alert reader may have noticed no mention has been made as to the origin/evolution of the laws of physics. With so much talk about the insights into the natural root of life and its various aspects, the fact remains that the origin of the laws of physics is not known or is knowable. That is the ultimate mystery. It is not knowable because the laws of physics are the only tool humans have at their disposal (tested and beautiful) to seek the truth about reality, the truth that can be shared among humanity that is independent of one's belief, affiliation, color, race etc. Obviously understanding the origin of the laws of physics is not possible using physics as a tool. So this very existence of an ultimate mystery will be a permanent source of a sense of wonder and mystical feelings among those who appreciate the beauty of the workings of the laws of nature. The laws which not only give rise to the fragrance of a flower, or the fascinating patterns of a snowflake, but also the ethereal quality of love in humans. The laws which create in the brain a sense of wonder at the working of the laws, and creates a sense of wonder at the creation of a sense of wonder at the working of the laws....
- The Evolutionary Origin of Morality
- Freewill vs. Predestination
- Soul, Brain and the Laws of Physics
- On the Nature vs. Nurture Debate
- Science and Aesthetics
- A Scientific View of Life Death Immortality:
- Brain and Religion