A VERY TALL STORY

Dick Pountain/21 August 2008 10:52/Idealog 169

I've just finished a first draft of my book about information theory, neuroscience and their implications for philosophy. Unfortunately it's missed this year's "holiday reading" window, but maybe next year? Nevertheless, this is an ideas column and I feel the urge to offer you an edited excerpt, which may assist you in arguing about religion down the pub. The story so far is that there's been a Big Bang and there's now a universe full of hot stuff whizzing around in all directions and shining all over the place. One such lump of hot stuff is the sun, and we all live on a ball of rock and water in orbit around it. Now read on...

Life on Earth exists, as Roger Penrose has so lucidly explained, not because of energy received from the sun but because of *low entropy* radiation received from the sun. The Earth re-radiates as much energy back into space as it receives from the sun each day: if it didn’t would become ever hotter and have evaporated millions of years ago. However it re-radiates in the infra-red at a lower frequency than the yellow sunlight it receives, and because each lost infra-red photon carries away less energy than an arriving sunlight photon, many more of them are needed and hence their entropy is higher. We live in this entropy gap between incoming sunlight and outgoing heat radiation, and ultimately on the fact that the sun shines brightly against the black background of space – if all the incident radiation were of uniform energy and came equally from all directions, there’d be no entropy gap and no possibility of order (that is life) arising anywhere. The non-uniform distribution of matter and radiation permits a local lowering of entropy and enables living organisms to arise and reproduce themselves by assembling simpler molecules into large orderly structures.

Once life arises, evolution generates life forms of ever increasing complexity, many of them equipped with some kind of sense organs that confer the ability to sample their surroundings - such organs greatly assist in finding food, avoiding predators and locating mates. This sampling involves the transfer of information rather than matter, though always via some material medium: for example vision samples light reflected from external objects; hearing samples pressure waves created in air by the motion of external objects; touch samples the pressure exerted on the body by direct contact with external objects. Only taste and smell require actual ingestion of external chemical substances, in tiny quantities. The end result is a stream of electrochemical impulses in the organism’s nervous system that is purely internal, but which encodes information about the external world.

The external world is filled with unevenly distributed, moving matter that exhibits forms (that is shapes, colours and so on) imposed by the basic attractive forces of physics. Living organisms sample these forms via their sense organs, store and process them encoded as electrochemical signals. It’s important to be clear that these forms are manifest in matter itself, whether or not any living being actually exists to see, hear, or feel them. They are not merely subjective. Later on organisms evolved brains that could store the samples garnered by their senses and recall them as memories, enabling them to partially predict the future by comparing current samples with remembered ones to discover repeating patterns. The brain of Homo sapiens alone confers an ability to use language to communicate these samples to other humans, and also supports self-consciousness, the ability to sample our own internal states and talk about them. Language also enables the human brain to manipulate samples in the abstract, separated from any external reference, which made possible mathematics, logic, science, art, imagination, poetry, error, delusion, hallucination and religion.

Of all these abstract abilities imagination is the most important. While many of our stored samples originate as perceptions from the outside world, our brain is capable of dismantling, rejigging and distorting these images and constructing new ones from them that correspond to no external object at all. An almost infinite number of forms are physically possible that don’t happen to be manifest in matter right here, right now, but our brain can construct them for itself (as for example when we remember a dead friend’s face). Some forms that are not physically possible at all can nevertheless be conjured up by the brain, as with demons or angels. We can have no absolute guarantee about the existence of external objects beyond what our senses tell us, but evolution has honed those senses so that they don't deceive us too often, and we make instruments and employ scientific reasoning to help them along. An actually perceived Number 29 bus and an imagined demon are both are only information patterns in the brain, and this being the case the way our brains are able to assemble something approaching a stable, coherent representation of the outside world - corresponding well enough to reality to permit us to walk and eat - is a real miracle.

In later chapters I engage in fisticuffs with Marx, Nietzsche, Freud and the whole of 20th-century analytical philosophy: "Sampling Reality" will be coming to a bookshop near you if anyone is mad enough to publish it.