Sophie Kern's illustration for In Search of the G SpotAtheism has recently had some eloquent advocates. Indeed, they have been so effective that they have provoked their religious opponents not only to criticise – often quite savagely – their grasp of theology but also to accuse them of being “fundamentalists”. Unfortunately, some of these brilliant deicides do indeed have their own fundamentalism, and this can lead to even more dangerous simplifications.

The ultimate meaning of religious belief, they assert, is biological; it is a property of the evolved brain. Theism is good for social animals, as it promotes solidarity and cooperation, thereby increasing the probability of the genome replicating.

The literature of “neuro-theology” or “spiritual neuroscience” is founded on risible simplifications which humanists should reject. Take a recent study, “The Neural Correlates of Religious and Non-Religious Belief”, headed up by Sam Harris, one of the most prominent defenders of atheism. Harris and his colleagues used scans (fMRI – or functional magnetic resonance imaging) to compare the brain activity associated with religious and non-religious beliefs (or disbeliefs) in two groups of individuals: 15 committed Christians and 15 non-believers. The subjects were scanned as they evaluated the truth and falsity of religious propositions such as “The Biblical God really exists” and non-religious propositions such as “Santa Claus is a myth”. In both believers and non-believers, and in both categories of stimuli, belief was associated with a greater signal in the ventromedial cortex. This is an area, the authors state, that is important for (take a deep breath): self-representation, emotional associations, reward, and goal-driven behaviour. However, religious thinking was more strongly associated with brain regions that govern (take another deep breath): emotion, self-representation, and cognitive conflict. Thinking about ordinary facts, by contrast, is more reliant on memory retrieval networks.

According to Harris [who responds to Tallis here], this study “furthers our understanding of how the brain accepts statements of all kinds to be valid descriptions of the world”. Moreover, it explains why, despite the predictions of Marx, Freud, Weber and others, the spread of industrialised society has not spelled the end of religion. It confirms what the anthropologist Pascal Boyer has asserted, namely that religious thoughts and behaviour survive because they are by-products of ordinary brain function. It is not because they have relaxed their standards of rationality that people accept implausible religious doctrines but simply because this doctrine fits their “inference machinery”. Religion is a spin-off of a more general trait to draw inferences beyond what experience tells us and to seek a coherent explanation of what is around us.

I have already discussed the serious methodological flaws in this kind of study (“Neurotrash”, New Humanist, November/December 2009). But once the glamour of high science is removed they don’t tell us all that much. To argue that religious belief is a manifestation of a more general belief-forming tendency – in virtue of which we make inferences about our surroundings that exceed our experience, so that we, say, expect a just rather than a random world, and seek an overall meaning in our lives – may seem to some to state the bleeding obvious. No brain scan is needed to demonstrate that we are sense-making creatures and the sense that is made might include the idea of a Sense-Maker or God. What is more, no brain scan can explain how it is that we make abstract, complex, general sense of things, or the particular sense that we make of things in general. In short, brain scans add nothing to our understanding of religion. It should not need pointing out that the instinct for divinity has distinctive features that simply can’t be reduced to brain activity. Nor can they capture any fundamental difference between religious and non-religious beliefs.

Since this might have been anticipated before the study, and was evident after the study, it is interesting to inquire why it was undertaken in the first place. What motivates Harris and some other neuro-theologians is, I suspect, the wish to cut religion down to size. The trouble is that this not only diminishes religious belief: it also diminishes all kinds of belief and, indeed, us humans who are believers. Irrespective of whether you are an atheist or a religious believer, to naturalise one of the greatest (for good or ill) and unique expressions of our humanity cannot be a good thing. Just how damaging this is to our sense of ourselves becomes apparent when we examine some of the other literature on the neuroscience of religion.

The crudest expression of the “neuralisation” of religion is the claim that there is a “God spot” in the brain. VS Ramachandran arrived at this conclusion by observing people who had seizures affecting the frontal lobes. They sometimes experienced intense mystical experiences and became obsessed with religious spirituality. He inferred that the seizures caused an over-activity in the part of the brain he called “the God module”. The British neurologist Michael Trimble also studied patients with epilepsy and concluded that God must be located in the temporal lobes, especially as these are the areas affected by LSD and other drugs that are supposed to induce spiritual experiences. Dimitrios Kapogiannis and his colleagues have claimed, in a paper entitled “Neuroanatomical Variability of Religiosity”, that religious belief is associated with a change in the size of different parts of the brain. Experiencing fear of God is associated with decreased volume of the left precuneus and the left fronto-orbital cortex BA 11, while experiencing an intimate relationship with God is associated with increased volume of right middle temporal cortex BA21.

More recent “God spot” spotters have been less specific. The neuroscientist Mario Beauregard recruited a group of Carmelite nuns who had had an intense experience of union with God and invited them to put their devout heads into an MRI scanner. He then attempted to locate the brain areas that were active when his subjects recalled the moments when they experienced the most profound connection with the divine. His God spot was all over the brain – more like a rash than a single spot. Other studies, such as those of Jordan Grafman, have also given God more spacious accommodation, encompassing not only the parts of the cerebral cortex unique to humans but also less salubrious locations in the more ancient parts of the brain shared with other primates.

God spot spotting has been complemented by God gene spotting. The observation that identical twins reared apart (in other words with different environmental influences) showed a greater than chance concordance on attitudes to Sabbath observance, divine law, church authority and the truth of the Bible seemed to some to support a genetic influence on religious belief. The medical scientist Robert Winston has suggested that a variant of the dopamine receptor gene (DRD4) – which reputedly has a powerful role in our sense of well-being – may be more biologically active in those who have a religious bent. Dean Hamer caused a big splash, and propelled himself to the cover of Time magazine, when he announced, in his book The God Gene: How Faith is Hardwired Into Our Genes (Doubleday, 2004), that a particular gene, vesicular monoamine transporter 2 of VMAT2, was linked to the trait of spirituality and religious belief.

The notion that religious belief is due to machinery in the brain fits with the idea that it has (as Kapogiannis puts it) an “adaptive cognitive function”. Religion is “hard-wired” into the brain because it is of evolutionary benefit. The communal sense conferred by religion, we are told, would have given groups of hunter-gatherers a more developed feeling of togetherness. Others, such as Bruce Hood in Supersense, have suggested that religiosity, though hard-wired, is a by-product of evolutionary adaptations – an exaptation or spandrel – and that it is an expression of the way our minds are structured. [Hood has responded to Tallis here]

All of this is reductive (which is for some the point) but also profoundly point-missing. The suggestion that God might be a tingle in our heads, rather similar to epileptic seizures, or a propensity to have such tingles, is to misconceive the nature of religious belief. We must distinguish between religious experiences (of well-being, of joy, of terror, of shame, of expanded awareness) and the translation of those experiences into, say, a revelation of a God with certain characteristics. Isolated brains or, even less, bits of brains do not have the wherewithal to make this translation, which depends upon many things; for example, the culture in which one has been brought up, one’s education, the kind of person one is. Admittedly, some of the studies I have discussed acknowledge that religion is a matter of belief rather than of the kinds of sensations one might have in a seizure; but, since they are unable to show a profound difference between religious beliefs and non-religious beliefs, they tell us nothing about the former. But there are other problems with the “neuralisation” of religion.

Take the God spot. What part of the brain, a material object, could one conceive of as housing the notion of something infinite, eternal, all-powerful, all-seeing, all-wise and yet systematically invisible? What kinds of nerve impulses are capable of transcending their finite, local, transient, condition in order to conceive something that is infinite, ubiquitous and eternal? Religious believers may explain how (finite) people manage to connect with the idea of an Infinite God: they are thought to have eternal souls that are non-localised. This can hardly be claimed of the brain. No one surely expects to find the idea of the Supreme Being, with all those almost unthinkable and often contradictory characteristics, in sodium ions passing through membranes in the limbic circuit or the frontal cortex.

There are other problems with “neuralisation”. Religion is immensely complex and certainly not simply a matter of experiences (if only it were!) or beliefs captured in sentences. It includes, among other things: a set of prescriptions for codes of behaviour and customs and practices that are to flow from those codes; a very elaborate nexus of institutions, expressing the mediated authority of a putative deity, that exert power in the private and public sphere in myriad ways; and the collective and individual sense of a hidden all-powerful agent underlying the totality of things and validating a set of beliefs about the origin and nature of the universe and of our place in it. Our engagement with these dimensions is not captured by discharges similar to those which are associated with epileptic fits or even with ordinary beliefs.

Religious experience, and all that follows from it, is in the keeping of the community of minds to which we belong: it is there it is interpreted, developed and maintained. This is where we must we must seek the source of the inspiration for cathedrals a hundred years in the making, the evolving styles of church music, the Catechism, the Council of Trent, confessional wars, and all the use and abuse of power that religion authorises. And the prescribed codes of behaviour that are connected with a multitude of shared ideas about the meaning of our lives, our relationship to others, our infinitely nuanced appreciation of right and wrong.

Neuroscience cannot capture this. Nor can evolutionary theory. Anyone who believes that churches and their institutionally mediated power can be understood in biological terms has to overlook that, unlike gene products, they are argued into place. Take, for example, the response to the Reformation by the Catholic Church – the 18-year Council of Trent that brought together delegates from many countries. The eternal debates that led to an agreement on a variety of canons and decrees do not look to me like anything that happens in the natural world.

And I can no more imagine cathedrals being built out of brain tingles than I can see a gene product requiring a Thirty Years’ War to defend it. Appealing to the pseudo-scientific notion of memes – the unit of cultural transmission analogous to the gene – is a desperate attempt to provide landfill to bridge the great gap between animal behaviour and human institutions – a gap that yawns widest in the case of religion.

An interesting, indeed dismaying, measure of the extent to which neuro-evolutionary accounts of religion have gained acceptance is that some believers have embraced the notion that God is hard-wired in our brain by evolution, as a way of defending their continued religious belief and reconciling themselves to the truth of Darwinism. Perhaps it is not an atheist’s place to second-guess the mind of God but I don’t think He would like being hard-wired very much. At any rate, He would be right to treat the notion with Divine Suspicion. If it suggests that our vision or intuition or experience of God is simply a good idea from an evolutionary point of view, isn’t the Almighty thereby somewhat diminished? It makes Him merely a useful notion to help one small part of the universe, namely human beings, ensure the replication of their genetic material. What a come-down for the Author of Everything to become a product of a tiny part of something! Darwinising the idea of God makes prayer and the holding of theological beliefs a mere organic function, a bit like secreting urine. If you naturalise belief in God, then it is very difficult to see how God can remain as a supernatural Being with all those characteristics that have been ascribed to Him.

Some believers might parry this last argument by saying that the biological value of entertaining an idea of a God does not touch God himself. He still remains the all-powerful, infinite, eternal creator of all things. What is biological is that in virtue of which humans gain access to him – their brains or whatever. Indeed, they may go further and suggest that God designed us in such a way that, by adaptations that have survival value, we come to have knowledge of him. He set in motion a process – evolution – that would eventually be destined to result in a creature that, for its own benefit, formed an image of God; that, in other words, God indirectly hard-wired himself into the human brain so that he could be ultimately mirrored in His creation.

This assumes, however, that the outcome of evolution was pre-ordained – and this is a profoundly anti-Darwinian idea. For at the very heart of Darwin’s theory is the operation of natural selection on random variations. Its outcome is not predetermined. As Stephen Jay Gould famously pointed out, if you ran the tape of evolution twice, there is no reason why human beings should emerge a second time.

So believers’ attempts to reconcile evolutionary theory with their religion, by arguing that such beliefs have adaptive value, because human groupings that worship the same Gods will have a better chance of going forth and replicating, must ultimately diminish religious beliefs to the level of other biological phenomena linked to survival – unless they also believe that God somehow rigged the outcome to ensure that these biological phenomena did emerge and so that He could guarantee His daily fix of worship. But the notion of God rigging the outcome would not be compatible with evolutionary theory, as I have already indicated.

At any rate His mode of rigging would leave much to be desired. Evolution is a shockingly cruel and inefficient process that has nothing to do with love, mercy or even common decency. Which makes it rather odd that God, seemingly indifferent to the horrors necessary to ensure the survival of the fittest, should, after letting rip nature red in tooth and claw in order to generate humanity on a pyramid of dead predecessors, then be concerned with the details of individual human lives – and, indeed, should have a late fit of morality, in which He intervenes with direct and mediated voices in the lives of men and women and guides them how to behave well and care for their fellow creatures.

What is more, biology does not distinguish between false Gods and The True One. And this is a very important distinction for believers. So far as biology is concerned, all that matters is whatever floats the sociobiological boat. But, if you believe the sacred books, God is very exercised by the difference between false and true Gods. His wrath on this matter is well documented. What is more, for many religions, the kind of survival that matters is survival of the spirit rather than of the gene-bearing flesh. Prioritising survival of the spirit would be an anti-Darwinian first for nature.

At first sight, it might seem that a humanist atheist like me should welcome the reduction of religious belief to tingles in parts of the brain. It will be evident now why I do not. The idea of God is the greatest, though possibly the most destructive, idea that mankind has ever entertained. The notion that all there is originated from and is controlled by a Maker is a profound and distinctively human response to the amazing fact that the world makes sense. This response is more, not less, extraordinary for the fact that it has no foundation in truth and, indeed, God is a logically impossible object.

How mighty are the works of man and how much more impressive when they are founded on an idea to which nothing corresponds! Cutting this idea down to size, by neurologising and Darwinising it, is to deal not only religion but also humanity a terrible blow. It undermines our uniqueness and denies our ability, shared by no other creature, to distance ourselves from nature. In defending religious belief against neuro-evolutionary reductionism, atheist humanists and theists have a common cause, and in reductive naturalism, a common adversary.

Read responses to this piece by Sam Harris and Bruce Hood

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