The catalyst for this post is a clip I saw on Youtube, "Answers in Genesis fails AGAIN"/ Reacteria" by Forrest Vaikai. In this clip, Vaikai criticises and seeks to debunk a Creationist's attempt to debunk evolution. The clip is interesting and I advise the reader to have a look at it (although this post will make sense even if you don't). What struck me about this clip is that both Vaikai and his Fundamentalist antagonist assume that inheritance, the fact that we derive characteristics from our parents, can be explained only and wholly in terms of DNA. This assumption is one that everyone seems to make regardless of how educated he or she is, even, it seems, religious Fundamentalists. Why do I have hazel eyes? Because I inherited a 'hazel eyes gene' from one or both of my parents. Why am I right handed? Because I inherited a 'right handedness gene' from one or both of my parents. Why am I interested in Evolution? Because I inherited an 'interested in Evolution gene' from one or both of my parents'. Of course, I am being slightly facetious but you get the point – this is the kind of thing almost everyone says these days. Yes, eye colour is genetic (eye colour is a consequence of genes that regulate the amount of melanin in the iris). However, handedness is not genetic (although many people believe it is). And, of course, to say that I am interested in Evolution because I possess an 'interested in Evolution gene' is patently absurd. Most smart people recognise that physical and psychological characteristics are the result of both nature and nurture and that one's interest in a particular topic is the result of experiences rather than DNA. However, in recent years, the tide has swung radically in favour of genetic explanations. This current fad in scientific thinking is regrettable – the problem with it is, firstly, that many people who espouse genetic explanations for physical and psychological traits and attributes don''t understand how DNA works and, secondly, that cutting edge science, science that has not yet filtered through to the general public, has found troubling evidence that the genetic explanations so central to the Modern Synthesis do not account for many conditions people assumed must be genetic. This is known as the 'missing heritability problem'. (One example, very relevant to me, is that fifteen years ago people assumed that schizophrenia was caused by a 'schizophrenia gene' but, when researchers went looking for it, they couldn't find it.)
I am not a biologist but I have a reasonable understanding of genetics. I will attempt, here, to give a brief description of how DNA works in a way that will make sense to people unfamiliar with microbiology. A strand of DNA, known as a chromosome, is a double-helix made of four 'bases' (adenine, guanine, cytosine, and thymine). These bases (or nucleotides) are paired up. Occasionally, for reasons which I think are still obscure, a section of the DNA separates from its partner strand and attracts messenger RNA which pairs up with that section. This is known as 'transcription'. The RNA molecule thus formed then floats out of the nucleus, where the DNA is stored, to ribosomes. Every three base section of DNA and RNA constitutes a 'codon' and the 256 different possible codons are associated with twenty different types of amino acid, the building blocks of proteins. Transfer RNA brings amino acids to the ribosome where they attach to the messenger RNA: in this way, the amino acids are brought together and attached to each other, creating a kind of proto-protein. This is known as 'translation'. Through a process that is also obscure, the length of amino acids is folded or fashioned into a proper protein which then goes on to perform whatever function that protein is supposed to perform in the cell. This explanation may still seem obscure to laypeople but the takeaway from all this is that DNA codes for the sequence of amino acids that makes up particular proteins. This is all it does; it does nothing else.
Once you get your head around the notions of 'transcription' and 'translation', if you are not blinded by ideology (like Richard Dawkins), great mysteries emerge. Consider that a human is made up of many different types of cell: liver cells, red blood cells, leucocytes, neurons, and so on and so forth. If we accept that DNA is the blueprint of the organism, and we recognise that every cell in an organism contains identical DNA (except gametes), we have to assume that a human's genome (her total DNA) contains blueprints for every single type of cell that makes up that human. We have to assume that the reason why a cell in bone marrow is different to a cell in the kidneys is because, in the former, some genes are 'turned on' that are not 'turned on' in the latter and vice versa. This obvious insight is the basis of the modern theory of 'epigenetics' – the idea that something in a cell's environment causes some genes to be turned on and others turned off. (Epigenetics is also the explanation offered for the empirical evidence that children of people who experiences famine are more likely to be obese.) Furthermore, consider that humans have five fingers on each hand and not four or six. Every cell in a hand has the same DNA as every other cell in the hand – but somehow the cells seem to be aware of other cells in the hand and adjust their growth and activity accordingly. Somehow cells seem to know not only what type of cell they should be but also where they are in the body – and this 'knowledge' can't come from DNA. (Cancerous tumours, by the way, can be considered the result of cells that 'forget' what type of cell they should be and where they are in the body.)
Any clear headed understanding of genetics and transcription and translation should lead one to recognise that the modern synthesis must be incomplete. But many supposedly clever people (including, from my experience, many psychiatrists) don't seem to realise this. One of the theories that has been in vogue for several decades is 'evolutionary psychology', although the enormous popularity of this theory may currently be waning, partly as a result of an improved understanding of genetics through studies such as the Human Genome Projects. The premise of this theory is that psychological traits have a genetic origin. I think evolutionary psychology is as much a pseudoscience as phrenology but many apparently intelligent people subscribe to it. Many years ago, I read in The Listener about a proposed hypothesis that people are 'evolutionary designed' to have group sex, that in prehistory this was the normal practice. An item of evidence adduced in support of this hypothesis is that women are capable of multiple orgasms. Of course, this theory is stupid – if people are evolutionarily designed to have group sex, why are there no cultures or populations in the world today who practice it? In early 2018, I completed a paper on Narrative Theory with Brian Boyd, a distinguished professor at Auckland University. He had written a book called The Origin of Stories (a deliberate nod to Darwin's Origin of Species) in which he sought to present an evolutionary psychology account of how story telling came to be such an important defining characteristic of human beings. He argued that story-telling must have adaptive value. Brian is a very nice man and a very smart man but I think, partly, he had fallen under the sway of Richard Dawkins's powerful rhetoric and, partly, he was jumping on a popular bandwagon. I simply find many of the claims made by evolutionary psychologists to be, if not false, unscientific, unfalsifiable. Consider the following rather typical claim made by evolutionary psychologists. Supposedly humans (and other animals such as cats) have a genetic, instinctive, fear of snakes. But how could this be possible? We would have to suppose that some portion of DNA codes for a protein that somehow codes for a pattern of neurons in the brain that somehow codes for a fear of snakes. This seems highly implausible. An evolutionary psychologist, today, might argue that it is not one gene that somehow codes for a fear of snakes but the cumulative effect of hundreds or thousands of genes working together. But this only kicks the can down the road, as I shall discuss in a moment.
I'll adduce another example which might suggest that the Modern Synthesis is incomplete. I recall in 2013 a number of family friends commented on the fact that I greatly resembled my father when he had been the age I was then. These resemblances are, of course, subtle – the shape of our noses, the prominence of our ears, the contours of our jawlines. Both my father and I are short-sighted and require glasses. I find it hard to believe, however, that these very subtle resemblances are the result of genes I have inherited from my dad. Take the myopia that both he and I share. Fifteen years ago, people might have foolishly assumed that I must have inherited a 'myopia gene' from my father (even though a myopia gene could never have arisen and become prevalent in prehistory, in a time before eyeglasses, because those afflicted with myopia would have been quickly weeded out). Today we know that there is no such thing as a 'myopia gene'. The number of people with myopia in the world has greatly increased since 1950 suggesting an environmental cause. Perhaps kids develop myopia because they spend too much time inside watching TV and computer screens and reading rather than outside focussing on more distant objects. This seems to me a reasonable explanation. (If I was an evolutionary psychologist, I might say that it wasn't myopia I inherited from my father but a love of reading, a love of reading that then caused the myopia.) However defenders of the modern synthesis have clung to the idea that myopia is a genetic disease by claiming that it is caused by very many genes working together (in the same way that an evolutionary psychologist might claim that a fear of snakes is the result of very many genes working together). But if we try to reconcile the Modern Synthesis with these claims, a serious problem emerges. The foundational premise of the Modern Synthesis is this: occasionally a beneficial mutation arises in a species and results in a phenotypic change that increases an organism's fitness (making it live longer and have more offspring); this beneficial adaption then spreads through time throughout the whole population causing the species as a whole to evolve. However, if a phenotypic adaption requires hundreds of genes to come into effect, it obviously cannot result from a single mutation because a single mutation can only affect one gene. If only one gene changes (as the consequence of a mutation) but it has no phenotypic effect, natural selection cannot act on it. The probability that a beneficial mutation can arise by chance and then spread to all members of a population is already small; the probability that a hundred beneficial mutations can arise and then all spread to all members of a population, when any individual mutation has no discernible phenotypic effect, is vastly smaller. The more we dig into the modern synthesis the more problems we find with it.
What about other resemblances between my father and me, such as our prominent ears? An evolutionary biologist need not suggest there is a 'Judd ear' gene; she might however say something along the following lines: "There are a number of genes responsible for the exact shape of a human's ears. What makes the difference is the number of times a particular allele is repeated in the DNA." I just sense that this type of explanation doesn't add up. It is difficult for me to pinpoint and articulate exactly the problem with such arguments as they apply to familial resemblances. It just seems to me that the physical resemblances between close kin are so subtle that they cannot be explained by DNA.
The arguments I am putting forward are known as Arguments from Incredulity. I am suggesting, among other things, that the hypothesis that a fear of snakes is somehow coded in a series of nucleotides on a chromosome must be false because it it simply absurd, unbelievable. The Argument from Incredulity is considered a fallacy in informal logic. One could defend the position, however, that pointing out the ridiculousness of an argument is a valid rhetorical strategy. Consider the following analogy. Suppose you are an atheist debating a creationist. You say, "What about dinosaur fossils?" The creationist replies, "Dinosaur fossils were put in the ground by Satan (in 4004BC) as snares to test our faith." How are you supposed to respond? You cannot prove him wrong. All you can do is say, "I reject your argument because it is preposterous. It makes me incredulous." The Argument from Incredulity is the only practical answer. Consider, furthermore, that while the Argument from Incredulity is considered a fallacy, reductio ad absurdam arguments are deemed completely fine, acceptable. But is there any difference between the two types of argument? Both are based on the idea that some notions are too incredible, to absurd, to be true. In a reductio ad absurdam argument, one is claiming that at least one of the premises of an argument must be false because otherwise it leads to an absurd conclusion. We are saying, in effect, "The conclusion is absurd. It makes me incredulous and should you as well." In an Argument from Incredulity, we are also saying that some notion is too absurd to be true. The difference between the two types of argument is simply that if you are faced with an argument of this type and find it plausible, you are likely to describe it as a reductio ad absurdam argument; if you find it implausible, you are likely to describe it as an Argument from Incredulity.
Let us presume that the Arguments from Incredulity that I have presented are acceptable enough that we can move on to what they must entail. It seems that we can present the following two premises. 1) We seem to inherit at least some physical and psychological characteristics from our parents and other kin. 2.) This inheritance cannot be explained wholly in terms of DNA. If we accept these two premises the following conclusion immediately follows: 3.) Some of our inheritance results from some mechanism or mechanisms other than DNA. Immediately my more alert readers and any evolutionary biologists who happen to read this blog will see the enormous complication it forces us to face. A human being begins life as a zygote, an ovum fertilised by a sperm. What does a zygote inherit from its parents? Well, the mitochondria in a zygote contain their own DNA (DNA that is always inherited from the mother) but the only real candidate to explain the bulk of inheritance is the DNA found in the nucleus, a combination of the DNA carried by the sperm and by the ovum – if we presume that inheritance must depend on something physical. If we accept 3.) and also consider what we know about sexual reproduction, we are forced to conclude that inheritance depends, at least to some extent, on a mechanism that is non-physical, immaterial, spiritual or mystical. This mystical mechanism (to use Dylan Thomas's words "the force that through the green fuse drives the flower") is what tells a cell in a human what type of cell it is and, in a foetus, what organ and appendage of the body it will eventually become part of. In this way, we can use science to arrive at the conclusion that the supernatural exists.
In writing the previous paragraph, an objection that could be levelled at the conclusion I have drawn occurred to me. I have suggested, in effect, that inheritance can only be explained in two ways – as being genetic or as being the result of something supernatural. In ordinary secular discourse, the usual binary opposition presented is that between nature and nurture. A social scientist of a previous generation (someone who came of age before Steven Pinker wrote The Blank Slate) might suggest that I share many psychological characteristics with my parents because I learned from them or imitated them when I was a child. I like philosophy because my father likes philosophy and I imitated him; I like reading fiction because my mother likes reading fiction and I imitated her. However such psycho-social theories do not explain why I have my father's ears. In the end, it is probably best to to propose a tripartite explanation for inheritance: nature, nurture and the supernatural. I believe a rigorous argument could be made for this but would be too long for this post.
This post is titled "Threading the Needle" for a reason. In this essay, I have argued that the Modern Synthesis is wrong and that the supernatural exists – but this does not make me a Christian. At this point, I would like to discuss someone I have mentioned in the past but have not described in detail, Rupert Sheldrake. Many of the arguments above are inspired by arguments he has made. Sheldrake is a very interesting person. He is a trained biochemist who helped make major discoveries in plant hormones. He is a Christian but not a Christian like William Lane Craig or Bishop Barron – Sheldrake's spirituality is informed by his experimentation with hallucinogenic drugs and his exposure to Eastern mysticism in India. When he returned to England, he also returned to the Church of England, not because he believed Anglicanism was true and Vedic religions false but because Anglicanism was the form of religious tradition he grew up with – he came home to Anglicanism because Anglicanism fitted best with his sense of personal identity. I suspect that Sheldrake believes all religious practices are ways of approaching mystic truths – no one religion is inherently better than any other. If you asked Sheldrake point blank, "Do you believe that Jesus is the son of God, that he died for our sins, and that only through belief in Jesus can a person go to Heaven?" he would probably dodge the question in the same way that Jordan Peterson does, although this is the only thing Sheldrake and Peterson have in common. Sheldrake believes in Evolution but opposes the Modern Synthesis and materialist atheism in general. It is not Sheldrake's Christianity that interests me but his attempts to try to scientifically prove the existence of the paranormal. Sheldrake has written a number of books presenting evidence of telepathy in dogs and humans. Probably, though, his most important contribution to the intellectual biosphere is his theory of Morphic Resonance. The idea behind this theory is that there is a 'memory in nature' – the reason an animal comes to resemble other members of its species morphologically is that this immaterial memory guides its development. Furthermore, similar kinds of thing, whether it be pigeons, rats, or crystals, can influence each other at a distance and over time, a kind of 'sympathetic magic'. Sheldrake has argued that human memories are not carried in the brain and has even gone so far as to suggest that the laws of physics are not laws at all but should better be regarded as habits that can change and evolve (a claim that I think goes too far). Naturally, Sheldrake has earned the ire of scientific establishment and he has been labelled a heretic, a purveyor of pseudoscience. But I find his ideas persuasive. Partly this is because his criticisms of the Modern Synthesis are ones I had come up with independently and partly it is because I have experienced some telepathy, clairvoyance, and precognition myself (although these instances of 'magical thinking' largely went away many months ago when my 'illness' completely resolved). Sheldrake may yet have the last laugh: the problem of missing heritability, a problem which only became apparent after the biochemical triumph represented by the successful completion of the Human Genome Project, signals that the Modern Synthesis must be incomplete. If inheritance is not wholly genetic, Morphic Resonance might be a possible explanation for non-genetic inheritance. Of course, Morphic Resonance might be wrong (it is difficult to test) and there may be other hypotheses that can account for the problem of missing heritability, but these other hypotheses may of necessity have to be immaterial, mystical.
At this point I shall summarise the argument. The Modern Synthesis cannot explain how cells in a multicellular organism such as human know what type of cell they are supposed to be and where they are in a body. It cannot explain the apparent fact that humans and cats are instinctively afraid of snakes. (Furthermore it cannot explain other psychological phenomena putatively presumed to be genetic, such as the hallucinations and delusions entertained by someone experiencing psychosis, sexual attractions, or what Pinker calls 'the language instinct'.) It cannot explain the very subtle physical resemblances between close kin. I am suggesting not only that the Modern Synthesis does not currently explain these empirical fact but the the Modern Synthesis will never explain them unless it is radically transformed. These are Arguments from Incredulity: if they are acceptable we are forced to conclude that inheritance involves some kind of immaterial mechanism. One possible candidate for such a mechanism is Sheldrake's Morphic Resonance and another is the Christian God, but these are only two among many possible competing hypotheses. The onus is on defenders of the Modern Synthesis to provide an explanation of how a sequence of nucleotides can translate into a fear of snakes, an explanation that would require an understanding of microbiology and neuroscience we are not even close to presently possessing. Until then our incredulity is justifiable.
There is a second reason that this post is title "Threading the Needle". In the same way that debates about Evolution are often framed as debates between Fundamentalist Christians and atheist materialists, debates about science come at the issue from polar extremes. On the one hand we have many people, often journalists, people without much scientific training, endlessly saying "Trust the Science" and advising the public to uncritically accept every study published in journals like Nature and Lancet. On the other hand, we have people who think the Coronavirus pandemic is an excuse by Bill Gates to implant microchips in people and that global warming is a hoax cooked by left-leaning academics or the Chinese government. In reality the truth is somewhere in between – there is good science and bad science. Recently I read Science Fictions: How Fraud, Bias, Negligence, and Hype Undermine the Search for Truth by Stuart Ritchie. In this book, Ritchie discusses the 'replication crisis', a problem in some ways as big or bigger than the problem of missing heritability. Ritchie argues persuasively that scientific researchers are often encouraged to make bold claims with little evidence and engage in questionable practices like 'p-hacking'; furthermore, they are discouraged from attempting to replicate findings that have already been accepted to see if the findings actually stand up because of the systemic bias of journals in favour of novel discoveries. The replication crisis is not a big problem for a discipline like physics but is a serious problem for medicine and the social sciences. Even the idea of 'priming', a psychological concept introduced by eminent Nobel Prize winning psychologist Daniel Kahneman that had wide support, has been punctured – studies attempting to replicate the initial research performed by Kahneman and Tversky that led them to invent the idea have largely failed. I strongly believe that much of the 'science' surrounding mental health conditions like schizophrenia is bad science but I won't discuss this here – it requires a standalone essay in which I dive into all the bullshit research surrounding schizophrenia, such as the supposed findings that (generally) schizophrenics lack verbal fluency, have difficulties with abstract thinking, possess 'fixed delusions', are promiscuous, display religiosity, and so on and so forth. Much of the research surrounding schizophrenia is attempting to find patterns in the data that don't in reality exist. However this is something I will talk about in more depth in a later post. I will though recommend Ritchie's book. (I might note that although I am talking about Sheldrake and Ritchie in the same post, they are very different. Ritchie can't be described as a pseudoscientist – rather he is an establishment scientist who happens to be critiquing the establishment.)
I'll finish this post by making a cynical point. Last week Auckland suffered the worst weather event in its recorded history – even my readers overseas may have heard about this. Climate scientists often say that global warming is increasing the probability and frequency of extreme weather events but it is usually difficult to attribute a particular weather event directly to climate change. The flooding in Auckland is different. We can quite rightly, I think, say it is the direct result of global warming. (Prior to the flooding, the ocean around New Zealand was 3 degrees Centigrade warmer than it usually is in summer.) For over twenty years, I have been arguing with my father about the existence of global warming. Let us suppose, counterfactually, that in 2005 the governments of the world had stepped up and found ways to stop carbon emissions getting into the atmosphere and reduce the amount of CO2 and methane already present. Climate change deniers would today still be saying such measures were unnecessary and claiming that governments had really implemented climate policies for secret nefarious purposes of their own. It is only because the world is going to shit that climate change skeptics are being forced to admit that they were wrong. So we lefties have been proved right. But it seems like a pyrrhic victory.
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