Much of this chat is no more than that, but some of the conversations across disciplines have proved to be extremely fruitful, although many of the scientists are now so entranced by the notion of consciousness that they overlook the fact that consciousness is just a special case of what we are doing all the time: making meaning. The brain used to be thought of as a kind of computer but it is now clear that brains are very different from computers. However, the marriage of the computer concept of neural learning to the physiological concept of neuronal networks, along with the results of research using non-invasive scanning of the active human brain, appears to be providing some part of the missing link between the functioning of the brain and the functioning of the mind. It seems possible that when we create a meaning we simultaneously create what the neurophysiologist and psychologist Susan Greenfield calls a ‘neuronal gestalt’.
Physicists have always been interested in finding the ultimate ‘stuff’ of reality of which everything is composed. At present they seem to agree that this ultimate stuff is quanta – tiny packets of energy. However, these quanta behave in peculiar ways very different from the kind of matter we humans can experience, and so there are currently two kinds of physics – quantum physics and classical physics, which is the kind of physics which explains why apples fall downwards and planes fly.
The big question for physicists is how to link quantum physics and classical physics. Subatomic particles behave very differently from the way in which we expect objects to behave. An electron will in one situation behave like a particle and in another situation behave like a wave. If you try to measure subatomic particles the actions of taking the measurements affect what you are trying to measure. Then there is the problem of the behaviour of a photon in one place apparently being able to affect instantly the behaviour of another far distant photon. Three solutions have been suggested for this problem of the link between quantum and classical physics, but each solution seems to suggest a reality which we humans could never see. Indeed, it is difficult even to imagine what this ultimate reality might look like.
Einstein argued that quantum particles have definite position and momentum but these are obscured by wave function. It is possible to imagine little quanta darting about at great speed, but then does this mass of tiny dots turn into a seething mass of something else which is itself an illusion? Niels Bohr said that the classical realm and the quantum realm never meet except in measurement, which suggests that we all operate simultaneously in two different realms. Hugh Everett said that there is set of actual states in which a quantum particle is simultaneously a wave and a particle, the implication of which is that there are many parallel universes. Being able to see an infinite number of universes would definitely be an information overload for us. More recently a number of physicists have talked about how time functions in the behaviour of particles, but the time physicists talk about is very different from the time you and I experience.
In short, physicists are showing that we cannot see reality, or, even if we could, we wouldn’t be able to deal with it.
If that is the case, what is it that we do see?
In 1994 Terence Picton and Donald Stuss summarized much of what had recently been discovered about the localization of brain functions usually associated with ‘being conscious’. They said, ‘The human brain forms and maintains a model of the world and itself within that world. This model can be used to explain the past events and predict the future.’2
That is, what our brains do is make a guess about what is actually going on and present that guess as a model or picture of ourselves in our world. Curiously, our brains not only construct these pictures, they also persuade us that, instead of the picture being inside our head, we are in the middle of the picture and it is all around us. As I am writing this I have a picture in my head of the gum trees at the bottom of my garden, but what I am experiencing is that I am sitting in my conservatory and looking at the gum trees at the bottom of my garden. Even as I look at the garden my picture is out of date. It takes my brain between a tenth and half a second to form my picture, so what I see my trees doing they have already done. Moreover, because my eyes, like everyone else’s, jump about, I have taken a string of snapshots of the garden, but my brain has turned these snapshots into a smooth, flowing film of trees waving in the wind.
Clever though my brain may be, there is much it cannot do. The models that our brains create are limited first by the basic physiological equipment we are born with and second by what our environment has to offer.
The physiological equipment which humans are born with is different from the equipment other animals have – in some cases very different. Take the humble octopus. It does not just sit there waving a tentacle or two. The New Scientist pointed out,
To plumb an octopus’s thought will require a huge leap of the imagination. As earthbound humans we are not even very good at imagining the world of other animals that move around in three dimensions. Scuba divers know how easy it is to be lost at the right place but the wrong depth … Cephalopods [which include octopuses, squid and cuttlefish] have boneless bodies and keen senses. Their complex eyes, as large as car headlamps in some deep water species, can distinguish detail as well as mammalian equivalents. Although cephalopods are thought to be colour blind, they can see polarized light, which we cannot. They also have highly developed senses of touch, taste and smell, and can detect gravity, a sense which is used in the co-ordination of muscles during movement. And in the past few years, researchers have even discovered what can be best described as hearing: fine hairs along the head and arms that, in cuttlefish at least, can detect disturbances made by a metre-long fish up to 30 metres away.3
Thus an octopus’s picture of the world must be quite different from our own. Even the domestic cat occupies a world very different from its owner’s. To claim to know what an animal is thinking is, in fact, to claim the impossible.
It is sad to think that cephalopods are colour-blind when to most of us humans the sea is full of colourful delights. Actually it is not, nor is the world a colourful place. What we see as colour is the response of the cones in the retinas of our eyes to different wavelengths of light. Our eyes respond to light, and so we see a world which is complex and detailed. Yet within that world there is much we cannot see. What we see as light is only a part of the electromagnetic spectrum, which extends from extremely low-frequency radiation with wavelengths of more than 1,000 kilometres to gamma rays with wavelengths measured in billionths of a millimetre. Only a narrow band somewhere near the middle of this spectrum provides us with wavelengths to which our eyes respond.
In contrast, plants ‘see’ much more of the electromagnetic spectrum than we do. They do not have eyes but they do have proteins latched on to light-sensitive compounds which can then harvest the packets of light energy called photons. They not only ‘see’ more wavelengths than we can see but they can also identify the intensity, quality, direction and periodicity of light. Most plants can also taste, touch and perhaps even hear. Plants create their own kind of meaning, but their construction of themselves in their world must be very different from our construction of ourselves in our world.4
When we see we do not simply record things in the way that a video camera does. When we see, wrote Richard Gregory, we ‘receive signals from the physical realm, and then create everything we see. Shape,