The notion that we might uncover the nature of the world through a combination of careful observation and logic goes back to the inception of the scientific project. It was the dream of the Enlightenment and it could even be said that this vision has defined modern western culture. A motivating and liberating force, it has given us a sense of progress, a sense that unlike previous cultures and other societies we are on the road to truth. Nevertheless, it is profoundly mistaken.
In the closing pages of A Brief History of Time Stephen Hawking took a sideswipe at contemporary philosophy, arguing that it has been reduced to an analysis of language. In his haste to dismiss philosophy he allowed himself to misunderstand not only language but the nature of the world. Hawking makes the simple error of assuming that the world and our descriptions of it might be one and the same. In our descriptions of the world we divide it into things: trees and houses, people and events, stars and planets, atoms and molecules. But the world is not a thing or a combination of things, for these categories-these closures, as I call them-are the outcome of our descriptions. Instead, the world is open and it is we who close it. Through our closures we grasp the openness of the world as things, and out of these things we build stories and models through which we are able to intervene. But these stories and models are not the world, nor could they in principle come close to being the world.
The world does not come pre-packaged and divided into its parts. We are not in a cosmic supermarket identifying cling-wrapped items of reality. Instead we find ourselves in openness, and in order to make sense of it, to have some means of intervening to certain effect, we realise closure. We do not form our closures in a vacuum. We find ourselves in a network of linguistic closures already realised and handed down by our culture from generation to generation. As biological organisms, we are already set up, through evolution, to generate certain types of sensory closure. These biological and cultural systems of closure have been adopted because they prove useful, not because they are true.
Current theories of astrophysics, with tales of the big bang, black holes and antimatter, have the feel of science fiction. And in a sense that is what they are: the stories of contemporary science. These stories are not unconstrained; they do not allow anything to be said. For the stories of science have an internal logic which drives them forward. They are often useful. We live by our closures. But we should not imagine that we have thereby captured the secrets of the universe. Nor should we suppose that there are not countless alternatives, offering other ways of holding the world that may be equally valid.
The closures of contemporary science appear to be unavoidable because they take their place in a system of closures that has been built and defended over centuries. When Hawking describes the universe as a vast array of galaxies exploding into the emptiness of space propelled by the energy from the original big bang, it is the outcome of a history of preceding closures which combine to make it look as if Hawking's closure is the only available option. Yet there are other options, at every level of the account, from the tiniest detail to the most general theory; options that would grasp openness differently in some respect, that would draw attention to different patterns and different connections, and which would as a consequence offer different ways of intervening and to different purposes.
In his new book, The Universe in a Nutshell, Hawking regards Newton's account of motion and his theory of gravity as the starting point for the contemporary scientific account of the universe. Instead, we should regard Newton as the initiator of a complex and elegant system of closures. Newton's centrality to science and to our culture obscures the limitations of his theory. We are dazzled by his importance and his influence and so overlook the mechanism of his closures.
Since Newton every schoolchild has known that the apple falls from the tree because of gravity. Yet gravity cannot be detected or identified. We see only its consequences. Newton replaced one mystery, the falling apple, with a more profound one, the existence of something that cannot be seen or touched, and which causes change instantly across any distance. Newton's explanation was no less mysterious than the explanation that the apple falls to the ground because God made it do so. We have become so used to the notion of force that it seems to us now to be almost mundane in character. Yet Newton's theory, which proposed that the world is awash with undetectable and mysterious forces, is bizarre. There is evidence that Newton himself was concerned about the essentially mystical core to his theory (as Einstein would later be about his).
There is also, throughout Newton's theory, a circularity: for the most part, the apple does not fall at all but remains on the tree. Newton has therefore to propose that another force is acting to keep the apple on the tree, a force precisely equal and opposite to that of gravity. And like gravity, this force is also undetectable. Force is Newton's explanation for change, but to any counter-example we choose to offer, Newton simply proposes a new force that is equally unidentifiable or provable. This circularity might appear a weakness, but the great strength of his theory was precisely that it could not be disproved. It is a circularity which ensures a solid core from which to build a system of closures. Where the theory proved useful, it could be applied. And where it was not, a complex amalgam of other forces could be envisaged to explain its failure. So gradually the web of explanation and closure grew. Over time, Newton's framework enabled others to extend and develop the system of closure until today we have the vast network of closures that make up the contemporary scientific account of the universe. Yet at its heart, the Newtonian system and its framework of forces remains as mysterious as when it was first proposed, and its seeming explanations are the circular outcome of a series of responses to previous failures of the system.
Prior to Newton and Copernicus, the Aristotelian and Ptolemaic system proposed that the behaviour of the stars and planets was to be explained by the movements of vast celestial spheres. This system in the context of Newton's framework and our current perspective is wholely preposterous. Yet for centuries it was capable of predicting the movements of the stars and planets to a remarkable level of precision. It was used by sailors to navigate across oceans and was even able to predict irregular events such as eclipses. The success of a system of closure is not due therefore to its having accurately described the world. Its success is due instead to its ability to enable to us to intervene in what we take to be reality. Closures are not powerful because they are true. We hold closures as true because we believe them to be powerful.
Thirteen years on from A Brief History of Time, Hawking has to admit, in The Universe in a Nutshell, that the goal of a theory of everything is no closer to being achieved. In fact, the structure of the new book is itself illustration of the failure of the grand project. For instead of a single unified account which gradually unfolds throughout the book, we have a series of piecemeal glimpses at aspects of contemporary physics. No doubt this structure was selected partly because of the demands of popular science, to make the book both different and accessible. But there is a deeper reason too. The attempt to describe contemporary physics as a single story makes the gaps and weaknesses more apparent. Piecemeal glimpses allow failures of the closure to be covered up and questions to be left unanswered. Moreover, there are signs that Hawking himself is beginning to become aware of the limitations of his own account. He now describes himself as a positivist, in the sense that we can only have evidence for choosing one model over another, rather than evidence for the model being reality. If Hawking took a further step and recognised that different models are not simply different accounts of the same reality but provide themselves different realities, he would have come closer to understanding the nature of the human predicament and the nature of the scientific closure that he is himself propounding.
If we are to make progress in understanding the nature of ourselves and the world we need a theory of closure. Without such a theory we are at risk of mistaking the mechanisms of closure for the mechanisms of reality. Such a theory will need to provide a detailed explanation of how it is that even though closure has nothing in common with openness it is still capable of enabling precise and effective intervention. It will also have to address the question of how it is that a theory of closure is itself possible.
A century ago Lord Kelvin declared, "there is nothing new to be discovered in physics now. All that remains is more and more measurement." Those like Stephen Hawking today who suppose that we are on the verge of finding the ultimate theory will be similarly embarrassed. If instead science gave up its metaphysical pretentions and stopped supposing that it was uncovering the essential character of the world, it would be stronger not weaker. It would be in a better position to entertain new theories, and new closures, which might enable more effective intervention in what we take to be reality. Just as science demonstrated the limitations of the closures of the church, so now we must come to terms with the limitations of the closures of science. We must see them for what they are: ways of holding the openness that is the world.
