to say, self-balancing unity. Perhaps the most striking feature of it is that it acts as though it ‘desired’ to maintain itself. But we do not say of the spinning of a heavy top which resists being upset that it ‘desires’ to go on spinning. The very constitution of the living-system may compel it to…14
And it follows that:
Life as an energy-system is so woven into the fabric of the Earth’s surface that to suppose a life isolated from the rest of that terrestrial world even briefly gives an image too distorted to resemble life. All is dove-tailed together.15
Animals do not exist by ‘being’; they exist by happening. An animal is not like a coffee mug, which was once made and now can be full or empty, warm or cold, sitting on the table or hanging from its hook, but basically the same ‘thing’, constituted of the same stuff, and continuing to be so until it breaks. An animal is like a whirlpool; it derives its relative stability, and even its form, from its motion, and it is only kept moving through its interactions with the wider system of which it is part. Try to take the vortex home in a bucket and you will be disappointed. Disconnect an animal from its ‘life support systems’ and it too begins to lose its form and fall apart into constituents that are simpler, more independent of one another, more dead.
There is nothing very mysterious about this view. It only needs stressing in the context of a lopsided scientific tradition which has taught us that the only way to know something properly is to take it to pieces, and study those exhaustively. This analytic, reductionistic approach works well in some areas of enquiry, most notably in the inorganic worlds of physics, chemistry and geology. But if you pull an animal to bits, whether literally or conceptually, it dies. It loses the integrity, the interwovenness that is its central defining characteristic. And it loses the form that only emerges as a result of this interwovenness.
The Inner Web
To understand the body, and all the complicated psychological harmonies that have been overlaid on this basic physical melody by evolution, we have to remember its essential embeddedness in the wider system of the world. But we also have to pay attention to the fine details of its internal make-up. An animal is composed of inner systems that are interlaced so finely that they too cannot exist, or be comprehended, simply as a collection of parts. No subsystem of an animal stands alone; the heart, the lungs, the stomach and the kidneys only make sense in terms of each other. You can look at their tissues separately under a microscope, and describe their structure. But if you want to get very far in explaining what they are, you will find that the boundaries between them rapidly dissolve.16
The same applies to the way animals behave. We have to see them as much in terms of inner co-ordination as of differentiation. Even a very small and simple creature has to keep track of three crucial aspects of its world: what, at the moment, it needs, or needs most; what opportunities the world is currently affording (as revealed by its stock of sensibilities); and what it is capable of doing, its repertoire of possible responses to differing combinations of desires and opportunities.
If your powers of perception are extremely limited – say to the concentrations of one or two nutrients in the stream you live in – and your needs are mercifully few – for example, that the levels of concentration of these nutrients are neither too weak nor too strong, and your actions are limited to orienting yourself in one direction rather than another (so that you can keep facing upstream), and opening and closing your pores…if you are as simple as that, then it makes sense for the connections between need, opportunity and capability to be clearly and unambiguously specified, so you do not have to worry about what to do next. You are a simple little soft machine, with reflexes that work to keep you alive, as long as your food keeps coming and your pores do not clog up. You are well adapted to a world that varies only within the limits that you are capable of responding to, and when it gets too hot or too cold, too dry or too salty, or when a family moves in next door that has things like you on its menu, then you have not got a clue what to do, and you and your kind are in trouble.
But our animal forebears rapidly grew to be more complicated than this, in almost every possible way. First, their physical structure is larger, and certainly more differentiated. They have specialized organs, each of which confers a range of new perceptual and behavioural abilities, and they found ways of moving about: using fills or wings or tails or legs. Their world comprises more needs (as each internal organ requires particular conditions to be able to work), and certainly more sensibilities and more capabilities. If you can see and smell and run around, life gets more interesting.
Now the perennial problem of prioritization, the question ‘What do I do next?’, is no longer a trivial one, and simple reflexes will not do. There are too many shifting contingencies for that to work. You need some sort of information system that will provide a way of letting the eye and the legs know what the stomach needs, and of letting the stomach know what is on the menu, so that it can lay the table with the right kinds of cutlery and condiments. You will be handicapped, in other words, if you are not able to co-ordinate the different aspects of your insides with each other, and to co-ordinate your system as a whole with the shifting kaleidoscope of threats and opportunities that are round about you. The price that any society pays for specialization is the need for internal communication – and the more complex the community, the more sophisticated its communication, both internally and externally, needs to be.
Walkie-Talkie
In simple multicellular creatures, a nervous system that keeps the different subsystems directly in touch with one another will do well enough. They can talk to each other by CB radio, without having to invest in any central administration. The Portuguese man-of-war, for example, is technically speaking not a single creature but a large sticky conglomerate of interdependent organisms who have decided to throw in their evolutionary lot with each other. Some of these are specialized for floating and providing buoyancy. Others engage in collecting and digesting of food, or in sensing different forms of incoming energy (who can tell by the stimulation of the water whether there is anything interesting in the vicinity, and if so whether it is likely to be a meal or an enemy). Others specialize in mounting guard and manufacturing ammunition for the poisonous tentacles. And others in planning and preparing for reproduction. This colony manages to co-ordinate its complicated set of senses, activities and needs without any central information point, or sophisticated nervous system, simply by enabling various sensory and response subsystems to talk directly to each other.17
Beyond a certain degree of complexity, however, this point-to-point form of communication begins to become cumbersome and inadequate. The system as a whole needs to be able to hold ‘conference calls’, as well as allowing each department to talk directly with one another. So evolutionarily there is a move towards greater ‘networking’ between the different systems, and eventually towards some kind of centralization – an office, like that which controls a fleet of taxicabs, which can keep an overview of what is going on, and co-ordinate the different activities. And at this point the distributed nervous system begins to develop into a ‘central nervous system’, the CNS. Not that there has to be any controller who sits in the ‘head office’, deciding what is best. The design of the animal CNS, and ultimately of its brain, as we shall see, is such that this kind of centralized decision-making about what is best for ‘all-of-me’, can be conducted very well by a communication system that is wired up in clever ways, so that the wiring itself determines how choices are made. No ghost in the machine is required.
Getting Around
One of the evolutionary moves that must have stimulated the development of the first brains was mobility: the discovery of the advantages of being able to get about. Couple mobility with a sensory system, and you are able not just to close your mouth and hold your breath when something nasty comes along, but to get out of the way. You are not dependent on what the stream happens to be serving that day;