Monday, May 24, 2021

A Soul Might Explain Instincts, but DNA and Brains Cannot

The discovery of DNA was one of the great triumphs of science. But ever since this discovery there has been a strange trend which we may call “DNA inflation,” “DNA exaggeration,” or even “DNA apotheosis.” The trend has been to carelessly describe DNA in ever more grandiose terms, regardless of the actual facts. One of the central myths about DNA is the idea is that it is some kind of blueprint for an organism. Another common claim is that DNA is a recipe (or a library of recipes) for making an organism. It is also sometimes claimed that DNA is like a computer program for generating our bodies.

But such statements are not warranted by the facts. Judging from the facts, we must conclude that while DNA uses a code of symbolic representations (the genetic code), DNA is not a blueprint for making a human, is not a recipe for making a human, and is not a program or algorithm for making a human.

There are several facts that dictate this conclusion:
  1. DNA does not store information in some general purpose language in which complex body plans might be stated. DNA stores information using a minimal, stripped-down “amino acid” language capable of listing only the chemical ingredients (amino acids) that make up a protein. Other than the word “stop,” the only “words” that you can state in DNA are words such as tryosine, valine, proline, lysine and serine, words that specify amino acids. Given such a limitation, no one can explain how DNA could possibly contain a three-dimensional blueprint for a body or a list of instructions for constructing an organism.
  2. If it were true that DNA had instructions for making the three-dimensional form of a body, we know of nothing below the neck of a female that would be capable of interpreting and understanding such instructions. Using 200 types of cells, each so complex and dynamic they have been compared to factories, the human body is a marvel of multi-level hierarchical organization, and is more physically complex than anything humans have ever constructed. Any instructions for making a human would be fantastically complex. Extremely complex instructions require something smart enough to interpret them, and just as there is nothing in a cell capable of interpreting something written in English, there is nothing in a womb that could be capable of understanding and executing three-dimensional assembly instructions if they were written in DNA. The idea that organisms arise because of a DNA blueprint is therefore a childish notion, like the notion that you could ride a balloon to the moon. 
  3. Despite cataloging the entire human genome, and exhaustively analyzing it, scientists have not discovered any part of DNA where a blueprint of the human body or a recipe for making humans is stored. For example, we have found no part in DNA where it specifies that humans should have two arms, two legs, ten fingers, ten toes and one neck; and we have found no part in DNA where it is specifies that heads and eyes should be rather round, or where it specifies the shape of the heart or the ear.
  4. If body plans were stored in DNA, we would expect a human to have vastly more genes than much simpler organisms. But the opposite is often true; for example, humans have fewer than 25,000 genes, but the rice plant has between 32,000 and 50,000 genes.
  5. The human genome is not big enough to store the body plan of a human, something that would require many more bytes than the mere 700 megabytes in human DNA.

So it is not true that a human baby develops from a fertilized egg because some instructions for making human are read from DNA. So how is it that morphogenesis occurs? How is it that a fertilized egg is able to progress to become a newborn baby? This is a great mystery of nature we do not at all understand. Such a mystery is an embarrassment to many types of thinkers, who want to think that biological life is something that has been pretty much figured out by scientists. Such thinkers will try to hide the fact that there is a gigantic secret of life we are quite ignorant about, and they will promote the incorrect idea that DNA is “the secret of life,” as if there were no gigantic secrets of biological life we don't understand.

There are actually six gigantic mysteries of life we do not understand:
  1. The mystery of morphogenesis, of how a fertilized ovum manages to progress to become a newborn baby. The mystery is unsolved because DNA does not specify how to build a human being or any of its 200 types of cells.
  2. The mystery of protein folding, the mystery of why newly formed linear sequences of amino acids (called polypeptide chains) form very rapidly into complex three-dimensional shapes needed for them to be functional.
  3. The mystery of the origin of life.
  4. The mystery of the origin of species and complex macroscopic biological functionality, which is not at all explained by the vacuous idea of random mutations and so-called "natural selection" (which is a misleading term because "selection" is a word referring to choice by an agent, and those who appeal to "natural selection" are referring to something that does not involve such choice).
  5. The mystery of the origin of consciousness and higher mental functions.
  6. The mystery of what causes organisms to have instincts.
Let us look at the question of instincts. Ever-prone to depict themselves as understanding things they do not understand, our scientists sometime suggest that we understand what causes instincts. They may suggest that instincts come from an animal's DNA. The idea is every bit as untenable as the idea that DNA contains instructions on how to build an organism.

Let us consider some examples of instinct. When a baby is born, it has an immediate urge to suck on its mother's breast. This is an instinct. But how could such a tendency ever be represented in DNA, which can only state groups of amino acids? There is no way in which DNA can express the shape of a breast or nipple, nor could it express any idea such as “move your mouth to this shape when you see it.”

Another instinct is the maternal instinct. Most mammals will have an instinct to protect their young. But how could such an instinct be expressed in DNA? Can we imagine, for example, that the DNA of a bear contains some little image of a bear cub, along with some type of message saying to protect this type of animal? Not at all, given the severe expressive limitations of DNA, something that is basically capable of listing only the chemical ingredients of proteins. A message such as “protect them” is utterly incapable of being expressed by the primitive “chemicals only” bare-bones language used by DNA.

In the animal world, we see many incredibly complex instincts. For example, spiders have instincts to build spider webs, bees have instincts to make complex hives, and some birds have incredibly complex instincts. According to one site, “The monarch butterfly makes a multigenerational 4000 mile annual trip in which descendants of the third or fourth generation know exactly where the first generation started.” Wikipedia.org tells us this:

"The monarchs begin their southern migration from September to October. Eastern and northeastern populations, up to 500,000 monarch butterflies, migrate at this time. Originating in southern Canada and the United States, they travel to overwintering sites in central Mexico. The butterflies arrive at their roosting sites in November. They remain in their roosts during the winter months and then begin their northern migration in March. No individual butterfly completes the entire round trip. Female monarchs lay eggs for a subsequent generation during the northward migration.  Four generations are involved in the annual cycle."


There is no plausible scenario by which such complex instincts could be represented in DNA.  Nor can we explain such instincts by anything in a brain. Sometimes people appeal to "hardwiring" in a brain. No one has ever discovered any effect by which particular types of wiring in the brain can explain complex behavior. "You're hard-wired to do this" is usually just fantasy talk.  The analogy of "hard-wiring" was stolen from the behavior of early electrical equipment.  A particular arrangement of wires in early telephone switchboards might create one particular communication effect that would not occur under a different arrangement. There is no evidence that particular arrangements of wire-like axons in the brain explain particular behaviors. 

Consider the case of sex and a human male. A typical young human male will have a very strong instinct to have sex with a human female. But about five percent of the human male population will have no such instinct. Instead, this five percent will have a strong desire to have sex with the male of the species. How can we explain this by imagining that the male instinct for sexual intercourse with females comes from DNA? We would have to imagine that some “do this” instructional information in 95% of males was not present in 5 % of the males. There is no genetic evidence that this is the case. Nor is there any evidence that the brains of homosexuals are wired differently than the brains of heterosexuals. 

In humans the ability of an infant to quickly pick up the language of its parents may be considered an instinct. Linguist Noam Chomsky has stated the “poverty of stimulus” argument, that the exposure to language that an infant gets is very inadequate to explain how quickly the infant picks up language. Linguist and psychologist Steven Pinker wrote a book called The Language Instinct, but he presented little or no evidence that DNA can explain language acquisition. On this topic professor of linguistics Vyvyan Evans stated this:

"For a Universal Grammar to be hard-wired into the micro-circuitry of the human brain, it would need to be passed on via the genes. But recent research in neurobiology suggests that human DNA just doesn’t have anything like the coding power needed to do this. Our genome has a highly restricted information capacity. A significant amount of our genetic code is taken up with building a nervous system, even before it gets started on anything else. To write something as detailed and specific as knowledge of a putative Universal Grammar inside a human infant’s brain would use up huge informational resources – resources that our DNA just can’t spare. So the basic premise of the language instinct – that such a thing could be transmitted genetically – seems doubtful."

Humans have innate language abilities that are very much like an instinct, but neither DNA nor brains explain this.

It is sometimes suggested that epigenetics might help explain instincts. Epigenetics is basically methyl molecules that attach to the outside of certain base pairs in DNA. But such molecules have all the same expressive limitations of DNA itself. There is no way in which behavior patterns can be expressed in either a genome or an epigenome.

The existence of instincts seems to be evidence for souls, not just in humans but in all animals that display instincts. If we imagine that an animal has a soul, we need not imagine that such a thing is some kind of blank slate. It may be that when particular types of souls start out in an organism, they have particular types of inclinations. Such soul characteristics may be the root cause of instincts.

DNA cannot explain instincts, and since current ideas of so-called natural selection depend on the idea of a change in genomes, natural selection also fails to explain instincts. As Gustave Geley stated in his very erudite book From the Unconscious to the Conscious“Now the origin of instincts is no more explicable by natural selection or by the influence of the environment than the formation of species.”

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