Evolutionary Psychology: A New Hermeneutic.
Recent insights gained from the fields of anthropology, cognitive psychology and evolutionary theory have shed new light on the neural origins of religious culture. Religious ideation is examined in the light of the discovery of domain specific neural mechanisms that have evolved in the human brain. These mechanisms attract and elaborate certain kinds of religious ideation. Thus their study provides an explanatory framework for religious texts and practices. This paper is an overview of this area with Judeo/Christian texts in mind. Rather than displace traditional methods of exegesis that are based on author intention and historical context, these insights provide some explanation as to why certain ideas are represented in religious texts and why they are elaborated by specific mechanisms of the mind and why they are easily transmitted via the oral tradition.
Evolutionary Psychology: A new Hermeneutic.
The use of the historical-critical method in biblical studies has transformed our understanding of biblical texts. Such approaches as form criticism, literary criticism, redaction criticism and others have contributed to the interpretative machinery that we bring to bear on ancient texts. All of these methods are oriented towards finding the meaning of texts. It is generally assumed that texts are formed out of the conscious intention to relate a history or a story that carries meaning. By and large, this is an adequate explanation of the cause of a text. However, it is not a complete explanation because there is evidence that unconscious neural mechanisms may influence the formation of certain texts and explain why some are culturally transmitted and others not. The argument of this paper will be that the evolved nature of the mind attracts certain kinds of subject matter such as, for example, an interest in cleanliness. The process of evolution has left us with minds that are particularly interested in certain aspects of life because these aspects were the subjects of evolutionary pressure in the past. There arises the possibility of a new method in biblical studies that will not concentrate on the interpretation of texts but upon how texts have been elaborated and transmitted because our minds are particularly receptive to them. Such a suggestion has been blocked in the past by our insistence that culture exists in a realm that is separate from our biology. Any move in this direction has been met with cries of “reductionism”. However, I would suggest that it is just as logical to understand the mind to be constrained by its structure as it is to see that the eye is constrained to see only certain wavelengths of light and the ear to respond to a limited bandwidth of sound.
In the last 10 years the science of cognitive psychology has demonstrated that human beings, universally, possess mind/brain (henceforth mind) mechanisms that are dedicated to dealing with many aspects of life. Tooby and Cosmides  argue that these mechanisms are modular in that they attend to particular inputs, are mandatory, unconscious and fast. For example, when we see a face we know immediately whether we know the person and if we do, connect the face to a name. This response is mandatory in that we do not have a choice about recognition and unconscious because the process is not one of rational deduction. Indeed we will see a face in a circle with two dots in the position of the eyes or in the features of the moon or in the clouds. We are uniquely attuned to the human face. We do not have to think about whom the person is - recognition appears almost instantaneously. When we think about the information that the mind has to process to perform this feat we understand that it could only be performed by a dedicated neural module designed for the purpose, otherwise recognition would be slow and the mind burdened with computational overload. This example appears commonsensical because it involves specific sensory inputs that produce an output in the form of face and name recognition. However, cognitive psychologists extend the idea of modularity to include higher cognitive functions that encompasses all kinds of thought. The idea of a massively modular mind is still controversial especially as to how integration across domains is produced and specific expertise is learned, but it is gaining increased support. In essence, this theory postulates that conscious thought is produced by many modules acting in unison and is therefore determined in specific ways. The existence of such modules fits with evolutionary theory in that they are thought to consist of adaptations that have been selected to perform specific functions, just as the eye is an adaptation to receive visual stimuli and the ear auditory. The theory of this new science is as follows. Before human beings spread over the earth they shared a common environment over a period of several million years - that is long enough for that environment to select genetic make up by natural selection. The thing that is interesting about this environment is that while it consisted of weather, physical environment and food resources, it also consisted of other human beings. This period in human evolution was remarkable in that we lived in small groups of hunter-gatherers, who shared food resources, defended the group against outsiders, cooperated in hunting and gathering, and in child rearing. Any adaptation that occurred that facilitated cooperation in the group would improve the fitness of the individual and would be preferentially passed down to the next generation. Language is at the center of these adaptations. These social adaptations consisted of neural mechanisms that were specialised in particular domains of human function. The mind is thus not a general-purpose computer that handles all kinds of information in an equivalent way but consists of a multitude of modules that arose as adaptations selected to process particular input from the environment. Social adaptations determined if exchanges were fair, formed coalitions against outsiders, recognised faces, inferred the motivation and traits of individuals, assessed wether a task was reaching its goal and what precautions should be taken in a dangerous situation as well as many others. The modules are triggered by the particular situation that the individual experiences. If he encounters a stranger then the module that is responsible for the formation of coalitions is activated, if a social exchange is in progress elaborate cheater detection mechanisms are triggered. We can imagine a whole range of specialised mechanisms that would facilitate decision making so that the individual does not have to think through each occasion. Part of the methodology of evolutionary psychology is a kind of backwards engineering in which we hypothesise about the mental skills required to live as an individual in a group of hunter-gathers. Armed with predictions of the kinds of mental skills required and with insights into our own experience, it is then possible to go into the lab, as it were, and find out if these domain specific modules actually exist in living human beings. This is a necessary step because not all predictions of the existence of adaptations are accurate. For example, it may be predicted that male humans should possess an adaptation that enables them to detect the ovulation of females. This gives an obvious evolutionary advantage because males could then target fertile females saving much sperm and time. However, we find that there is no such adaptation; human males do not possess the ability to detect ovulation. This kind of unsubstantiated thinking has made many of the predictions of sociobiology unreliable since there was no move to test whether an adaptation existed. In other words, the psychology that must have been involved was ignored. The discipline of evolutionary psychology seeks to correct this error by looking for the proximal mechanism predicted by the ultimate mechanism of evolutionary process.
All this is not to say that human beings are automata whose behaviour is triggered by certain stimuli in the environment, but much of our behaviour and affect are. Show almost any women a baby and thoughts and feelings are triggered to do with motherhood. Show a male a nude female and sexual responses come into play. Place us in a situation of danger and our heart rate is likely to go up and our breathing become heavy. Show us a cockroach and we will react with disgust. While these modules produce both behaviour and affect in our day-today lives, we are not necessarily at their mercy, we do possess an executive capacity that will help us think through a new situation and to behave in a new way. Revulsion to cockroaches may be tempered by exposure. It is also not to say that there is no learning involved in human development. It is envisioned that these modules exist in the mind of infants and mature along with wisdom teeth and the sex organs but are shaped by experience. That is, neural tissue is prespecified to perform specific tasks but require environmental input to become fully mature. This is affirmed by studies on cortical plasticity in the sensory systems. It is the prespecified mechanism that is innate and therefore genetically transmissible.
The kind of learning that forms a mature neural mechanism is fundamentally different from conscious learning since it serves to structure neural mechanisms to function in certain ways that are not conscious. An obvious example of this is the acquisition of language. The idea that infants are born with an innate or pre-specified aptitude for language acquisition and use is widely supported by the linguistic community,. This mechanism receives stimulation from the language that surrounds the child and the child learns to understand and speak that language. This is a much too complicated feat to be arrived at by imitation because it involves all kinds of grammatical rules. Children do not learn to speak by imitating the sentences they hear which are often unique events. Learning to speak grammatically is an example of something that is underdetermined by the experience of the child, that is, the stimulus is not rich enough to account for the learning involved. In the linguistic field this is known as the poverty of the stimulus. This may be compared to how reading and writing is learnt. In contrast to language, reading and writing are recent occurrences in evolutionary time and hence are not associated with a particular adaptation. How such consciously learned aptitudes arise in the nervous system is still a topic of much debate. While all children learn to speak if they are exposed to language, particularly when the parent talks to the child, children do not become literate by watching others read and write or by looking at texts; a laborious learning procedure is required.
This hypothesis about how the brain works is called nativism or essentialism and the mechanisms, because they are genetically transmitted, are said to be innate.
There are some interesting consequences of this theory. Firstly, it means that all human beings from the Inuit to the Nuer are equipped with minds that are wired in the same way to facilitate social interaction and much other behaviour. This must be the most cogent argument that science has produced against the idea that there exist separate races. There may be superficial differences in facial features, stature and skin colour but these are trivial compared to the commonality of our neural mechanisms. For example, it is found that women all over the world speak to their new born with the same prosody, indicating that mothers intuitively use similar sounds to sooth, elicit attention, and indicate approval or disapproval. This occurs in the context of the many different languages spoken by the mothers.
Further evidence for the existence of neural modules comes from the occurrence of specific deficits in neural function. For example, prosopagnosia is a dysfunction characterised by the failure to recognise faces while all other visual and cognitive functions are intact. People with autism lack the ability to intuit other people’s beliefs, they are deemed to be “mind blind” or to lack the module that produces “theory of mind”. As these modules are characterised by psychological research it is increasingly clear that our conceptual function is constrained by the neural networks that are triggered in particular circumstances. Human minds are not clean slates upon which experience writes, (as John Locke would have it) we carry preprogrammed, special purpose computational mechanisms that guide thought, produce affect and behaviour and influence the structure of society, our political institutions, our sexuality, the structure of our families, and our religious ideas.
The mistake that has been made in the past by social scientists of all kinds is that the diversity of culture argues against a relationship between culture and a common biology. However, ever since Chomsky’s prediction that all human beings possess a universal grammar we have had a major theory that links the diversity of human language to a common neural mechanism. There arises the possibility that religious ideas are grounded in similar such mechanisms. Pascal Boyer,,, a cognitive anthropologist who worked in the Cameroon on the religion of the Fang people, has argued that there is a poverty of stimulus in the learning of religious traditions. The elders of the tribe do not have to teach the children every detail of the religious tradition for them to become fully functioning members of that tradition. Rather, children fill in the gaps of knowledge in a similar way in which they learn language. This paper is about exploring the kinds of modules that we would expect to contribute to the formation of religious belief. Kirkpatrick and Boyer have argued that we would not expect neural mechanisms to be specifically devoted to religion because it is not specific enough to produce a dedicated adaptation. While it may be argued that having religious belief may be a positive aspect that increases fitness, evolution can only produce adaptations to specific problems that our ancestors confronted. “Religion”, however, refers to such a diverse and multifaceted constellation of beliefs and behaviours that it is highly unlikely to be the product of a unitary adaptation with a single identifiable function.” It is therefore doubtful that there is a “God spot” in the brain that produces religious experience or behaviour. This means that religious experience and behaviour are produced by adaptations whose domains lie in the ordinary and everyday. The following is an attempt to explore the kinds of adaptations that would underlie religious belief and action.
Boyer comes to the conclusion that the transfer of religious belief and practice to the next generation is underdetermined in a similar way to that of language acquisition and that religious ideas are constrained by a kind of universal grammar of ontology centered around an intuitive ontology of natural things. All of the things in the world may be categorized in terms of PERSONS, ARTEFACTS, ANIMALS, PLANTS, INANNIMATE OBJECTS that carry with them certain inferences that deliver explanations of their likely states. The evidence that such intuitive categories exist comes from anthropological work that demonstrates that “those categories virtually exhausts cultural variation in this domain.” There are also developmental studies that indicate the existence of such categories in young children.The following scenario is plausible. When a child sees an object that moves in an intentional way, circuits in her mind evoke the category ANIMAL . This process would be innate. However, how does the child learn to distinguish cats from dogs etc. This learning through the experience of other animals would refine categories and concepts and extend them. However all of these will exist within an overarching knowledge about the properties of animals: that they die, need food, act in an intentional way, and breed in the same way that others of the same species breed. In other words, the inferences that our minds produce when we see a mouse or a knife or a brother are constrained by the categories ANIMAL, TOOL, PERSON respectively. This scheme is speculative, for example, we do not know how much information the innate structures contain. Again the comparison with language is apt, there are certain rules that structure concepts and these underlie the learning of new concepts. A theory of learning that does not rely on innate mechanisms that allow such learning to get off the ground is far more difficult to conceive. Lock’s clean slate does not help us understand how the brain learns, we might as well think of the visual system as being similar to a camera.
It is obvious that if ontological categories were innate that they would help to systematize the conceptual world. We would not expect a tool to move of its own accord or to have intentional behaviour or speak to us. This constrains the limitless associations that we might have when we see an object or an animal. When a child sees a rabbit her response is not guided by long ears or fur or by a thousand other inferences, but by the inferences that are associated with the ontological category ANIMAL. It is in this way that the mind limits its response to an experience and excludes the many responses that would overload the brain’s computational capacities. This is how the mind deals with what has been called the “frame” problem.
Boyer proposes, from anthropological data, that religious conceptions are characterised by a violation of intuitive inferences or by the transfer of an inference to an inappropriate category. An example of an inference violation is illustrated by how ghosts are understood. Ghosts carry all of the inferences of PERSON, that they move about, remember, can hear what others say, and have intention. They differ from the ordinary in that they also carry a violation of the inferences carried by the category PERSON in that they are immaterial and can therefore pass through walls and appear instantly. A familiar example of a transfer of an expectation from one category to another is the talking snake in the garden of Eden: an ANIMAL possesses the inferences of a PERSON.
The interesting thing about violations of inference is that they act as indicators of salience. When subjects are told stories, some naturalistic and others that contain an inference violation, it is the latter that is remembered over the former. The appearance of a talking snake in the second creation story acts as just such a salience marker. This is also why the form of literature known as magical realism works. When we read in Calvino’s “Our Ancestors” of Viscount Medardo who was bisected by a cannon ball and returned home only half a man, we are in the presence of an inference violation, a person who has lost half of his body continues to live and carries with it only half of his personality. This violates our innate sense of what makes a person but it is also rich in inference. What would half a man be like? Likewise the talking snake carries with it inferences of danger and deception, the inferences attributed to a snake are mixed with that of a person. This literary device would not be as effective if the snake were to be replaced by a golden Labrador. The evidence from personal experience is that snakes evoke responses of fear and disgust. It is likely that these responses are produced by innate mechanisms produced over millions of years. The fact that some peoples revere snakes indicates that culture can overcome nature. A golden Labrador does not evoke such responses and thus would not be as effective as a character in the story as the snake. These rich and counterintuitive inferences produce a fascination in us and have a heightened salience so that they are easily remembered. The inference violation lifts narrative above the ordinary and the expected. This will also mean that such a narrative will tend to persist in a population through transmission. Sperber has elaborated an epidemiological theory of culture that seeks to understand why certain ideas persist in a culture and why others do not. The inclusion of an inference violation in a narrative increases the likelihood that it will be remembered and transmitted. We would expect that such violations would be plentiful in narratives that have been preserved in an oral tradition because there are more occasions for a narrative to be elaborated before a text is produced and such opportunities lost. Compare the letters of Paul that have few such violations, to the abundance in any of the gospels.
Liberal Protestants have generally explained miracle stories in the bible by indicating that the writers lived in a prescientific tradition and hence did not know how the world worked. But we are talking about people who built cities, went to war, planted and harvested crops, made wine, and raised cattle. The idea of someone feeding five thousand with 5 loaves and two fish was just as preposterous to them as it is to us, as is the possibility that someone could walk on water or still a storm or raise the dead. Biblical miracles are examples of inference violations, a certain amount of food carries with it a sense of how many people it will feed, someone walking on water violates what we understand about buoyancy and the dead are objects that do not walk around and speak to people. This opens up the possibility that miracle stories have been transmitted in the tradition, not because they have any particular theological point, but because of the kind of story they are and the attraction that they have to certain modules in our minds. If this is the case for some of the miracle stories, then exegetes who search for a theological meaning may be wasting their time. Every preacher has experienced the frustration of trying to interpret yet another miracle story told by Mark. It is sometimes the case that such an interpretation is a little stretched. This does not mean that the gospel writers have not used miracle stories to make a theological point, but it does mean that the inference violations included, aids memory and transmission, and that that increases the salience of the story apart from any theological salience that is present in the mind of the evangelist. For example, accounts of historical events will be aided in their transmission if inference violations are added. Witness the two versions of the escape over the sea of reeds in Exod14:17-14:31 betrayed by the existence of the many doublets in the text. The earliest version ascribed to the Yahwist has many naturalistic components whereas the Priestly version has supernaturalistic. For example, the Yahwist writes of the dividing of the sea: “The Lord drove the sea back by a strong east wind all night, and turned the sea into dry land” (Exod14:21) while the Priestly writer has: “The Israelites went into the sea on dry ground, the waters forming a wall for them on their right and on their left” (Exod14:22). While wind driving a tide is natural, water standing in walls is definitely not; it is a violation of what our inference systems tell us about water. The Yahwist describes the demise of the chariots of Egypt as being the result of God clogging their wheels (Exod 14:25) whereas the Priestly writers tells us that Moses stretched out his hand over the sea and it returned to its normal depth. (Exod 14:27a) How did it come about that we have two versions of the one event that the redactor spliced together? What was the cause of the supernaturalistic elaboration? Part of the answer to these questions is hidden in the politics of Israel as well as the urge to a grandiose theology that increases the power of God. However, when we understand something about the epidemiology of ideas and how various neurological modules attract certain expressions, then we understand that there is more going on. These stories compete with each other in a way that mimics the process of evolution. Instead of the survival of the fittest we have the survival of the most intriguing.
It has been assumed that the gospel narratives were under the theological control of the evangelists and this is obviously true to a large extent. However, the narratives are also driven by unconscious and automatic mind function which produces, among other effects, the elaboration of significant cognitive violations. This explanation of the text exists at the level of causation whereas normal exegesis exists at the level of interpretation. These are not mutually exclusive methods; theologians must continue to seek the meaning of the text. However, an understanding of how cognitive function elaborates cultural expressions is a very useful tool, much like form or literary criticism in that it adds to our understanding of how the text was formed. In the following it will become apparent how previously opaque texts may be explained at the level of the modular structure of the mind.
An understanding of the function of inference violation in religious thought sheds light on how we understand God. In all traditions supernatural entities are PERSONS. We may have trees or mountains to which are added the inference of PERSON but we never encounter an entity that is a PERSON who carries the inference of a tree or a mountain. Therefore we may expect that the systems in our minds that have evolved to facilitate interaction with others will be the same that we use when conceiving of a supernatural person. God therefore thinks, regrets, feels, plans, is angry and is merciful. God also has a “strong right arm” and a face. These anthropomorphisms tell us that we use the same mental systems to relate to God as we do with people. There are many examples in the Christian tradition of inference violations of the category PERSON. For example, Mary is a person who has a special biological feature, the ability to produce a child without sex. Jesus is a person who performs feats that are not normally features of a person. It is apparent that only ontological violations signify the supernatural. A woman who gave birth while remaining a virgin is an ontological violation, while a woman who gave birth to 60 children, while remarkable, is not. In the history of traditions it is the former that would be remembered. We may ask if one ontological violation is good, two or more may be better. Not so, says Boyer. It is almost never the case that two violations exist in the one conception. He gives the example of prayer to a famous statue of the virgin. People may come from all around to stand within earshot of the virgin to pray. The inference violation is that an inanimate object carries the inferences of a PERSON and is able to hear the prayers of the believer. However, there also exists the understanding that the virgin hears all prayers no matter where they are said. The violation in this case is that a PERSON does not have to be within earshot to hear the prayer. We have here two distinct violations, one that an inanimate object hears and understands and the other that she is able to listen to prayer in many places at once. People never combine the two, they never pray to the statue at a distance, but they may pray to the virgin. This is how conceptual contradictions about God may coexist, as long as they are not held at the same time. It would be ridiculous to think that once the host had been transubstantiated into the body of Christ that it would know all things.
Barrett and Kiel have found that people attribute different properties to God depending upon whether they make theologically correct definitions of God in the abstract or whether they tell a story about God or, we could add, the properties of God inform religious practice. The abstract qualities attributed to God by adults are that he has no physical or spatial properties, is able to know and attend to everything at once, and has no need to rely on sensory input for information. However, when comprehending narratives about God, the same adults mistakenly remembered the God of the narratives as having a single location in space, as being unable to attend to multiple events at once, and as needing to see and hear in order to complete otherwise fallible knowledge. Thus abstract notions about God may carry many ontological violations while the God of narrative is much more like a normal person. While it seems it is easy to attribute to God multiple category violations in the abstract, it is like ticking off a list, as soon as narratives about God are told, our minds are constrained to a minimum of violations. Thus the God of narrative demonstrates more of the constraints of the person. Is this because a narrative which contained an agent with multiple violations would be logically impossible, or because there exists a module that receives and tells stories that can only deal with agents as persons and can be stretched to deal with an agent with minimum violations of the PERSON category? In any event, these considerations raise interesting questions as to the origin of religious ideas and our construction of theological schemes.
The inference violation that pertains to supernatural entities is never trivial. For example, the statement that; “There is only one God! However, He exists only on Wednesdays.” appears to us as absurd. Whereas the statement: “There is only one God to whom all hearts are open, all desires known and to whom no secrets are hidden” strikes us as a genuine religious statement. Why does one statement seem silly and the other appear in our liturgies? It seems that our intuition that one statement is silly and the other serious is just that, an intuition, something that our minds produce without conscious thought. This is a similar mechanism that tells us what information constitutes gossip, i.e strategic information that is important to how we act in the world. A God that exists only on Wednesdays is irrelevant, but a God who knows all our inner thoughts is highly so.
The latter example from the liturgy is an example of our attributing to God the inferences that pertain to the category PERSON; that we are endowed with “theory of mind”. The inference violation consists in God having perfect insight into our innermost thoughts whereas we have a much reduced capacity to intuit motivation and mood. This is but one example of how the structures of our minds, in this case the adaptation that has allowed us to intuit others motivations and affect actually produces an idea about God. This is a rich inference that may be used by liturgists to prepare the people for worship.
One of the most important adaptations in the human mind is the one that assesses social exchange. We have very finely tuned mechanisms to detect cheaters. Leda Cosmides has shown that this is a particular domain specific mechanism. The evolutionary setting is obvious, it is very important when cooperating with another to make sure that you are not cheated. It is interesting that children have a very finely tuned sense of fairness. When pouring the cordial on the kitchen bench it is very important that each glass holds exactly the same amount of drink otherwise we will have an argument on our hands. Similarly, adults will attend sales even if the savings are small because they expect a social exchange dividend. If God has all of the inferences of a PERSON then we would expect believers to attribute to Him the dynamics of social exchange. Israel was a nation that thought of itself as being in a covenant relationship with its God. The existence of the sacrificial system would suggest that that covenant was understood as more of a contract than a covenant of grace. Was there a development here that started with social contract and ended in the prophets and the New Testament with a covenant of grace?
The idea of sacrifice, so prevalent in the Old Testament and in the New with regards to the theology of the atonement and subsequently of the Eucharist, is an idea that is dealt with by our social exchange mechanisms. The idea that Jesus died for us, giving his life as a sacrifice for many snags the mechanisms in our minds that deals with social exchange. That the proposal bears no relation to the exchanges we encounter in everyday life is irrelevant. As soon as we encounter the proposition that someone has done something for us, our intuition prompts a response: are we beholden to that person? When theological explanations snag our intuitional mechanisms, they are more likely to be incorporated into our understanding. In this way they are “natural” ideas in contrast to the learning of scientific conceptions. This has important repercussions for systematic theology which, like any scientific pursuit, aims to proceed unencumbered by subjective bias. The realisation that our minds are more receptive to certain kinds of representations, like social exchange, provides a new opportunity to examine the basis of Christian doctrine. For example, the theology of the atonement may be formulated, not in terms of an exchange but in terms of the unveiling of human evil in the light of the grace of God and the triumph of that grace. While this concept may require more “scientific” thought and hence will not transmit easily, it is a much richer construction than the crude “Jesus died for us” approach. However, it is the latter that will more easily find acceptance.
It is obvious that automatic responses to sources of contagion would be an advantage particularly to individuals living in the Pleistocene in which many natural toxic and disease carrying substances abounded. It is probable that adaptations arose to protect the individual from sources of contamination from faeces, rotting meat and people carrying disease. Evidence that such an adaptation exists can be found in the stereotypical response of disgust. This response appears to be particularly oriented around taste and ingestion but extends into social mores and moral actions. As with much of the above there is continuing debate about the involvement of biology versus culture in the kinds of things and actions that are deemed to be disgusting. This debate mirrors the nature/nurture debate about the origins of religious ideas except that in the case of the existence of a contagion system, there is an obvious adaptive function. Nevertheless, it is obvious from the various cultural variations of what is deemed disgusting that the contagion system attracts cultural expressions in a similar way that Sperber speculates has happened in musical culture. This approach seems to be more promising when it comes to explaining the taboos, prohibitions on touch, and food that are found, for example, in Leviticus, than those explanations based on structural anthropology with its notions of polluting substances as being out of place, or on relying on our supposed aversion to being reminded that we are like the animals. Having said this, while it is obvious that a contagion system would produce disgust and therefore avoidance of faeces, rotting flesh, or infected individuals, it is much harder to explain why various animals should be avoided as food: “These are unclean for you among the creatures that swarm upon the earth: the weasel, the mouse, the great lizard according to its kind, the gecko, the land crocodile, the lizard, the sand lizard, and the chameleon.” (Lev 11:29-30) These go far beyond what one would expect from a contagion system that is to do with pathogens and seems peculiarly obscure for a nomadic people in the environs of the Middle East. There are many peoples who would think nothing of eating the above and we can only suggest that the list is a cultural phenomenon the basis of which has been lost.
My thesis is that some religious prohibitions against touch or the eating of certain animals has its basis in an intuitive contamination system that is the product of evolutionary processes. This system produces intuitions about contamination, that once something has been touched it remains touched until some kind of cleansing occurs. This is a kind of sympathetic magic that until the discovery of bacteria had no physical explanation. Like any of the inferential systems, the contamination or contagion system is easily evoked by suggestion, in this case that such and such an animal, person, object or bodily discharge is polluting. For example subjects found great difficulty drinking from a glass that they saw harbouring a cockroach even after the glass was disinfected. Similarly, once it is suggested to a congregation that the common Eucharistic cup may be a source of contagion, the move to intinction is hard to suppress.
However, this cannot be the whole story because it is difficult to see why menstrual women should be included in the list of the untouchable (Lev 18:19). The sight of blood or gore is salient as a visit to the abattoirs or any number of horror movies demonstrate. However it is hard to see how this could trigger the contagion system especially since meat was not exactly available in plastic packs at the supermarket. As Leonie Archer has commented, the blood of circumcision is holy whereas the blood of menstruation is polluting. That we do not have an automatic response of digust at the sight of blood would argue that the contagion system is not involved. Archer provides a convincing cultural explanation of the different attitudes.
While it seems reasonable to postulate that prohibitions and taboos may be the result of the activation of a contagion system, this is by no means the most interesting aspect of the phenomenon. Disgust is also elicited by immoral action. There is thus an association between righteousness and cleanliness as the prayer of preparation illustrates: “Cleanse the thoughts of our hearts that we might perfectly love you.” This connection is taken up by many biblical texts: “Who shall ascend the hill of the LORD? And who shall stand in his holy place? Those who have clean hands and pure hearts, who do not lift up their souls to what is false, and do not swear deceitfully.” (Ps 24:3,4) This connection, between cleanliness and moral behaviour, has no rationale and even less theological basis and hence is a prime candidate for having its basis in mandatory neural mechanisms. If this is true then once again we have a case of the structure of the mind producing a cultural expression. This may be why much popular Christianity places so much emphasis on morality, because our minds are attuned to such considerations.
It is a common notion that religious difference produces sectarian strife - that Protestants and Catholics of Northern Ireland hate each other because of theological differences. Pascal Boyer points out that there are many places in the world in which people with religious differences have lived peaceably side by side for generations. He makes the point that, although it appears that religious difference produces suspicion, hatred, and violence, the case is otherwise. There is nothing specific about religious difference or any other difference that leads to conflict between groups. Sectarian violence is a similar phenomenon to football violence, and patriotic wars and has a lot in common with the training of soldiers. This is not to say that there are real economic, social and political factors behind the wars of the nations. However, it would not be so easy to recruit armies of young men to lay down their lives if it weren’t for the phenomenon of coalition formation. Soldiers must dehumanize the enemy in order to kill them and to save themselves from psychological damage. There must be a clear distinction between them and us, insiders and outsiders, even human and inhuman. We need only to look at the supporters of football teams and the obvious pleasure individuals take in belonging to a side and their devastation at loss, to be convinced that an underlying adaptation is at work.
The phenomenon that is at the base of these is not difference, although that is used as a means of identification, but the habits of the mind that form coalitions. The evidence that we are wired to form coalitions can be easily demonstrated in laboratory conditions by simply assigning groups of people to either the red team or the blue team and by giving them a competitive task to do. It is soon noticed that members of one group begin to see the members of the other as inferior or wanting in some way. It is not difference that is the trigger for the formation of coalitions, but the perception of a threat from another group. When this happens, difference becomes significant and is magnified in a negative way. For example, during the Second World War Japanese Americans were given a much harder internment than German Americans. It is obvious from the propaganda of the time that the distinctive Asian features of the Japanese were a trigger to harsher treatment and more intense public prejudice. Boyer speculates that coalition formation evolved so that members of small hunter gatherer groups were able to work together in dangerous or threatening situations in a similar way to that of a platoon of soldiers. For this to happen, members of the group must be held in solidarity in times of danger. Coalition formation may involve brutalisation of individuals as a sign of the cost of desertion. This may explain initiation rituals that are more about brutalisation than instruction. A sense of superiority over other groups is a part of this process, even suspicion and dislike.
The Old Testament provides many examples of coalition formation, particularly in the circumstances of the conquest of the land. “Do not defile yourselves in any of these ways, for by all these practices the nations I am casting out before you have defiled themselves.” (Lev 18:24) It was necessary that the religious practices of the “nations” be regarded as defilement (see the section on pollution) so that Israel was able to take the land from its inhabitants. When coalitions are formed against a particular group they displace the activity of other systems of the mind that would lead to compassion, such as theory of mind. The reason that the enemy may be killed without remorse is that they are not seen to be human, we cannot read their minds and so cannot understand that they have exactly the same responses that we have. The New Testament also has many examples, Samaria and Israel, Pharisee and Sadducee, Roman and Jew.
Coalition formation is aided by establishing a way of identification of who is in and who is out. Thus food laws, arcane rites, dress, observances and hierarchies can all act as identifiers of who belongs and who does not. If the sole function of these identifiers is to facilitate coalition formation and hence strengthen the group then the explanations that are given for them may be misleading. In the section on pollution we puzzled over why certain animals were unclean since they did not produce feelings of disgust. It may be that the lists of unclean animals were made in order to separate out the people of Israel from their neighbors. This is not about divine law but the survival of the group. Similar phenomenon may be found in Islam and in most religious systems.
The mission to the gentiles by St Paul became caught up in these considerations. Should gentiles be circumcised when they join the church, should they eat meat offered to idols? The expansion of Christianity into the Greek and Roman world necessitated the breakdown of coalition formation. This led Paul to write: “There is no longer Jew or Greek, there is no longer slave or free, there is no longer male and female; for all of you are one in Christ Jesus (Gal 3:28). We will observe later in this article that this is not the only evolutionary adaptation that is challenged by the gospel.
A natural idea is one that is easily dealt with by innate mind mechanisms, adaptations of the mind. As we have illustrated, these ideas have to do with the kinds of adaptive problems faced by human beings in evolutionary history. On the other hand, scientific ideas are ideas that are not dealt with automatically by evolved modules, like reading or writing. But if Sperber is right and the mind is modular from beginning to end, that is, there is no function carried out in the mind that is not modular, how do we deal with scientific ideas like mathematics or leaning to play an instrument? Sperber argues that it is inconceivable that there could be a non-modular adaptation that could deal with general information and solve general problems. For what evolutionary pressure could such an adaptation be responding to? Evolution is by nature domain specific. However, modules may function on input for which they were not originally adapted: naive physics comes into play whenever we engage in a sport and the modules adapted to detect the harmonics of the human voice are used to listen to music. But what work does the mind do when it learns a non-natural or scientific task? Perhaps it is a matter of integrating the necessary modules in such a way that the task may be carried out in a way that is unusual for the organism. Thus learning to write is a matter of co-opting the modules that direct hand movement in relation to an object in space coupled with the modules responsible for remembering patterns coupled with the language areas. Learning to do an unnatural task might be difficult because we are using higher level modules to force connections that are unusual. The repetition that is required in learning may be the work that we need to do to reinforce the unusual connections.
When we understand the adapted mechanisms that are evoked in various situations we are able to discern the superficial explanation of religious behaviour from the unconscious/ intuitive. A distinction is often found between intuitive or untrained conceptions, and conceptions that have been formed in an academic discipline. For example, a student must be taught the difference between a teleological and a causal explanation. This is because it is natural to think in terms of purpose; a leaning that is particularly strong in the biological sciences. Students will often explain that the heart pumps blood in order to oxygenate the tissues of the body instead of giving a causal explanation in terms of the function of cardiac muscle and the operation of cardiac valves. Teleological explanations may then be called “natural” because we find in ourselves a natural inclination to think that way. Academic discipline requires that we override affects and behaviour produced by adaptations. Pathologists must overcome the promptings of their contagion system in order to examine a putrefying corpse. Students of physics must overcome their intuitive physics that tells them that a heavier body will fall faster than a lighter.
This has important repercussions when we consider the ease or difficulty of teaching religious ideas and their consequent transmission in a tradition. Relating to a supernatural being in terms of the category PERSON is a natural idea. All of the inferences of such a relationship are inferred from the category except for the inference violation of immateriality. Relating to God in terms of the Trinity is not a natural idea because we have no mechanism in our minds that automatically deals with a person who is three but at the same time one. This is why most people who think in Trinitarian terms usually do so in terms of the separate persons or Modalism. We can think in terms of Father, Son, and Holy Spirit as separate persons but to assimilate the idea that “these three are one” is much more difficult. The other alternative, for obvious reasons, is Unitarianism. The difficulty of assimilating a proper understanding of God as Triune is obvious from popular Christian piety and by the time that the church spent sorting this doctrine out and the controversies that it generated. This means that believers, unless they are given fairly sophisticated theological education, will not incorporate the concept into their belief system. Teaching someone to believe in the Trinity is like teaching someone Newton’s laws of motion, they are counter intuitive and are not dealt with in a simple way by existing mental adaptations. This is contrary to the analysis of McCauley who regards all religion as natural( intuitive) while all science in unnatural (rational).
Cultural ideas that are dealt with easily by mental modules and which have high salience, either from their meaning or because they contain an ontological category violation, will be easily absorbed into individual minds and easily transmitted between minds. This is Sperber’s epidemiological theory of culture. When we look at the rise and fall of Christian churches there are lessons here for us. Denominations that rely on a high degree of sophisticated theology do not do as well as those who appeal to intuitive religious ideas. The scientific nature of much of Christian theology demands that it be transmitted by academic structures. It is similar to the practice of natural science in that it requires a robust academic tradition for its maintenance. In other words, traditions of thought that are “unnatural” require the support of culture in a way that those that rely on “natural” or folk or intuitive resources do not. Hence much effort must be spent on such traditions to keep them from falling back into what may be called “native” culture. When scholastic traditions fail, popular Christian understandings quickly revert to the stock of natural ideas and become like native religion.
The question arises as to wether, in its development, the religion of Israel made the progression from natural to scientific in its conceptions of God. As we have noted, there is much in the Old Testament that fits with conceptual adaptations. However, what we may call naive religion comes under the criticism of the prophets, the narrative history of Israel and the legends (Job, Jonah). The ark cycle in 1Sam 4 is a case in point. This is a story that undermines the ideas of natural religion that assumed that Israel was in coalition with God who would ensure victory via the presence of the ark. We may say that the religious development of Israel was on the road from the natural or intuitive, to the scientific, even though many of its conceptions still depended upon the triggering of adapted mechanisms. What was the special talent of the theologians of Israel that produced this progression when all around them, the religious conceptions of the Babylonians and the Canaanites and the Egyptians remained intuitive? The cue to this is the use of the word “scientific” to indicate observation and rational inference. Natural or intuitive religious ideas are largely immune from outcomes. If the farmer prays for rain and it does not come he does not jettison his belief in a God who is able to answer his prayer. It seems that people who hold intuitive religious beliefs hold them in a different way than they hold their knowledge about the world. Their belief in a God who answers their prayers does not stop them from ploughing the ground and planting the seed. Religious ideas and knowledge about the world are qualitatively different. The history of the religion of Israel represents a movement from intuitive or natural religion, to scientific religion by the observation of historical events and the nature of the world and human life. How else could we explain the book of Job? The religion of Israel, existed in the tension between the intuitive and the scientific. The writers of the New Testament continued in the way of the Old in that they were obviously influenced by both natural and scientific ideas about Jesus. For example, the tradition of the resurrection treats the dead Jesus as a person to whom all of the inferences of PERSON were attributed except for the obvious violations. However, the theological development of the Old Testament ensured that the Jesus movement did not degenerate into native or intuitive religion. Jesus did not become an ancestral ghost among others. While the early church insisted on the presence of Jesus among them, this was a different presence in that it consisted of the ongoing effect of Jesus’ ministry and death. It did not depend upon a ghostly presence although this interpretation may be made from the resurrection stories. The monotheism and materiality of Israel prohibited such understandings.
The genius of Israel was that it sought a veridical theory of God in a similar way that small children seek theories about how the world works. Alison Gopnik thinks that we possess an urge to form causal maps of the world in the same way we produce geographical maps. So as scientists seek causal theories of the world, Israel sought theological theories that interpreted the world to them The fact that Israel is a modern nation and Babylon is not bespeaks the fact that religious systems are not all of equivalent adaptive advantage.
The primary assumption of natural theology is that God has organised the natural world according to His purpose. Natural science will thus always be a kind of theology as it was for Newton and his contemporaries. Scientists of the 17th century were mired in teleological thinking. It was thought that God had placed every hair on the smallest insect for a specific purpose. Teleology of this kind finds its origins in Aristotle’s biology. But why did Aristotle have this idea and why do students of biology automatically fall into this trap? There arises the possibility that there exists a module in our minds whose function is to explain the world in terms of purpose and that this is responsible for our almost automatic teleological thinking. It is difficult to speculate as to the adaptive significance of such a module. What problem was this module “designed” to solve? Surely causal explanations such as have come about through the practice of natural science are more useful than teleological explanations which are not really explanations at all. There is evidence both from ethnographic and psychological studies that we have a tendency to detect human-like agency in the environment that may not exist. This is a familiar phenomenon recognised by parents in young children who insist that noises in the night are caused by some kind of agent. It may be that this is the result of a module in our mind that was adapted to detect predators in an ambiguous environment. We would expect such a module to err on the side of caution and therefore tend to signal the presence of an intentional agency when none exists. The implication for religion is that people would tend to posit agents, perhaps of a counter intuitive sort. If an intentional agent were posited then it would become a subject for the theory of mind mechanism. Here we have a basis for teleological thinking, the intuiting of mind into natural events. This means that we understand natural processes as purposive: the basis for natural theology. It may be the case that teleological thinking actually comes from the module that is responsible for theory of mind. As well as intuiting the motivation of another person it is also capable of intuiting the motivation of the mind it believes is in or responsible for natural processes or events. This would mean that we do not sharply distinguish between human and animal mind and also attribute mind to non-biological processes like the weather. That we attribute human mind to animals is no surprise as anyone who has owned a pet or been entertained by cartoon animation will bear witness. The attribution of mind to non-biological processes is common in ancient and native religion but has become rare among the inheritors of natural science. Aristotelian biology may then be explained in terms of the application of the theory of mind module to natural processes and events and is a “natural” idea. The pervasiveness of this idea, up to the 18thC in the West and the difficulty involved in overthrowing it, even in the minds of modern students of biology, would support this conclusion. If this is the case, then the Christian adoption of teleological thinking in the form of natural theology may be attributed less to the logic of the argument than to the activity of our theory of mind.
That complex organisms, including ourselves, arose by pure chance is counter intuitive and explains how many still do not accept the theory of evolution. We have seen above, in the case of the contagion system, how theology often follows and rationalises intuitive thinking, perhaps natural theology is just another case in point. That this is so is supported by the way natural theology persists in the face of evidence to the contrary as is so often the case in religious thinking. Natural theology was undermined in the 18th C by the awareness of grotesque births both in animals and in humans and by the occurrence of natural disaster, particularly the Lisbon earthquake of 1755. Despite all the evidence that God does not control His creation, natural theology or teleological thought persists, indicating a deeper origin of this kind of thinking. This is why so much effort is still being spent on proving that the universe has at its centre a divine intelligence, despite the complete lack of evidence. Modern science, both biology and physics very happily goes about its business without the God hypothesis. It seems that we cannot let go of the idea that there is purpose behind the structure of the universe and we continue to seek the hand of God in it. While this question obviously has existential ramifications, its persistence may be caused by the kinds of minds that we have.
If certain theological formulations are products of our mental adaptations and therefore “natural” how do we regard them in comparison to those formulations based on “scientific” thought. The examples of natural religious thought in the Christian tradition discussed above were to do with the following adaptations; theory of mind, contagion, coalition formation, and social contract. As the scientific disciplines had to root out teleological thinking in order to produce real science, does theology have to travel a similar path? We have seen how Jesus and the prophets began just such a task when they criticised the automatic social exchange thinking of the temple, confronted the way that the contagion system isolated the sick and the unrighteous and questioned the formation of coalitions. It seems that the good news of the gospel was in part the news about being free from unexamined automatic thinking. Christian theology is a mix of natural and scientific ideas. On the one hand we have the doctrine of the Trinity an obviously scientific idea, on the other hand substitutionary theories of the Atonement which fits into the form of social exchange. Both are respected theological understandings. The danger inherent in natural ideas is that they are constrained by the kinds of minds that we have. Such ideas run along predictable lines. This was certainly not good enough for the development of natural science because of its subjectivity. If the proper object of theological thought is the history and literature of Israel and the life and death of Jesus plus the church’s reflection, then theology is in the same position as natural science in that it seeks truth about an objective reality. Of course, theology works with its own methods that cannot be compared to that of natural science, but they are both endangered by subjectivity. This is why academic theology differs from popular belief.
The new evolutionary psychology, even in its infancy, promises to provide new insights into the origins of religious ideas and hence of religious texts. This will be an important avenue for biblical studies and theories of religious practice because it will produce causal explanations of previously obscure phenomenon that seemed to defy interpretation. It will also shed light on the expansion and transmission of religious traditions. As the discipline develops we may be able to address the causal components of religious ritual that have previously been mysterious. This work does not displace traditional exegesis that is focused on meaning, rather it will be a powerful instrument in explaining how texts, beliefs and practices came to be as they are.
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