There are about 100 billion neurons in the average brain, so densely interconnected that there is a potential pathway that can be found between any two. Our intermediate-level brain-mind language has to respect what we know about the brain, but reduce this massive complexity into an image or a model that we can use to talk about the actions, needs and experiences of sophisticated animals. Over the last fifteen years or so brain researchers have revived a level of modelling first developed by Canadian neuropsychologist Donald Hebb back in 1949, in his classic book The Organisation of Behaviour.24 Hebb’s achievement was to devise a way of thinking about the brain that was faithful to what was then known about its real biological nature, but which was easier to visualize. The revival of this approach, known as ‘neo-connectionism’, has drawn heavily on work in Artificial Intelligence, the science (or perhaps the art) of writing computer programs that simulate aspects of what people do, and the ways they do them.
Let me give you a rather fanciful metaphor that captures the main ideas behind this kind of thinking. As you will see, even this simple image rapidly becomes quite intricate: the next few pages are the most ‘technical’ (despite the picturesque language) of the whole book. But bear with me. I shall not give you more detail than is necessary to follow the rest of the story as it unfolds. Without this overview of the brain-mind, and the way it does what it does, it will be difficult to understand how it is that the developing science of the mind offers us a radically new way of interpreting religion and religious experience.
The Octopus Discotheque
Imagine a small tropical island, perhaps a few hundred metres across, that has been colonized by a large troop of unusual octopuses who have turned it into a 24-hour-a-day discotheque. At an octopus disco you do not move around much. You all pile up in a big heap, and you extend your tentacles in all directions until you make contact with another octopus’s head. In fact we should really call these particular creatures ‘centipuses’, because they have not eight legs, but hundreds. These legs vary in length considerably, so that some of those whose heads you are touching are beside you, while others can be right across the other side of the dance-floor.
Octopuses, who need their rest as much as anyone, cannot stay awake the whole time. In fact, at any moment, only a small proportion of the total clientele is actively awake. You can tell when an octopus is awake because its skin turns from a dull grey colour to a bright lobsterish pink – as if it has been boiled. When it is awake and ‘dancing’, all it does is make small movements of the tips of its tentacles, thereby making their presence felt by all those other octopuses it is touching. Each octopus can affect its contacts in one of two quite different ways. If it tickles, the octopus on the receiving end is irritated and stimulated, and becomes more likely to wake up itself. But if the first octopus caresses, the other is relaxed and calmed, and is inclined to fall asleep (or more deeply asleep, if it is already asleep). Strangely, these caresses mean that if octopus A has been giving octopus B a gentle, tranquillizing massage, B will become more responsive to other sources of stimulation as soon as A falls asleep.
Each octopus wakes up when the total amount of tickling it is receiving from all the others who have their tentacles on its head, exceeds a certain amount. Like human beings, some octopuses are generally very sensitive, and will wake up and start squirming with only a couple of tickles. Others are heavy sleepers, and it takes the concerted tickling of dozens of tentacles before they come to and join the dance. And others are choosy: they will respond to tickles from certain other octopuses of whom they are fond, but will be more resistant to the approaches of those they care for less.
There are actually three kinds of octopus: those that live on the windward side of the island; those that live on the leewards; and those that live in the middle. Those on the windward have some of their tentacles resting in the sea, and they can be woken up, as well as by tickles on their heads, by particular patterns of waves. These are called the Lookout Squad. It is their job to detect the ripples that are caused by approaching ships, or impending bad weather, or other influences that might disturb the fun. On the other side, the leeward, are the Bottle Squad, whose job it is, if tickled in various ways, to stuff messages in bottles asking for help, or more music tapes, or whatever. In the middle are those who simply pass the tickles around.
The combined effect of this curious collection of stimulating and tranquillizing influences is to ensure that only a small proportion of the assembled company is awake at any moment. And it also ensures that the group of awake octopuses keeps changing. A couple of tentacles start tickling you, you wake up and start swishing your own tentacle-tips; but soon you start to get tired and drowsy, or to succumb to the relaxing massage. So if an observer were hovering over the island on a clear night, she would see these patterns of pink octopus bodies continually shifting around; and she would see a general increase in activity if the wind got up, or if a boat was sighted; and sometimes she would see a flurry of activity on the leeward shore as a bunch of messages were scribbled, stuffed into their bottles, and hurled out to sea. And the observer would notice that the pattern of activity at any moment was likely to be quite widespread throughout the network, not bunched up. She would be more likely to see an irregular pink ring extending across the whole island, rather than a concentrated pink blob.
The observer would also see, if she hovered long enough, gradual changes in the way the patterns of activity moved through the total octopus population, and this is because each time one of octopus A’s tentacles is successfully involved in waking up octopus B, the spot on B’s head where A’s tentacle is resting develops a little bit of extra long-term sensitivity. Now the next time A tickles B, the net effect on B is greater, and fewer other contributing tickles are needed to make B wake up. So the more often A and B are awake at the same time, the better A becomes at wakening B on its own. And the more likely it is, when A is awake and tickling, that it will be B that is roused, as opposed to Z, who A is also tickling, but with whom it has a less successful track record. What is more, if a number of octopuses are regularly involved in each others’ awakenings, then they will develop into a ‘gang’ – what Hebb called a ‘cell assembly’ – who will tend to turn on or turn off as a unit.25
Priming
One very important feature of the octopus colony is that, even though an individual or a gang may be asleep, they may be sleeping more lightly or more heavily as a result of stimulation which is not yet strong enough to wake them up fully. So if an octopus or a gang of octopuses, A, can sometimes awaken gang B and sometimes gang C, which one actually wakes up – i.e. which direction within the octopus colony the flow of ‘wakefulness’, or activity takes – will depend on the relative level of this ‘priming’ of B and C, as well as on the long-term state of their connections to A.
In fact this phenomenon of priming can operate more generally than between single octopuses, or individual gangs. We could suppose that buried in the tangled heap are groups of octopuses with different musical tastes. For one group Miles Davis tends to make them sleep more lightly, while Madonna lulls them into an even deeper slumber; for another group, Madonna gingers them up, while Mozart makes them insensitive to almost anything. Thus the ‘path’ that the area of wakefulness takes through the colony depends on what music happens to be playing. The difference might be sufficient to make A wake up B when the background music is jazz, but C when it is Country and Western. In other words the behaviour of the whole community is highly context-dependent and situation-specific. The effect of