From Philosophy Now magazine.
All the same he (Hawking) is compelled by the ‘abstract logic’ of his own doctrinaire science-first approach to push that evidence temporarily out of sight when declaring the total irrelevance of philosophy for anyone possessed of an adequate (i.e., scientifically informed) worldview. Indeed it may be good for philosophers occasionally to remind scientists how their most productive thinking very often involves a complex interplay of empirical data, theories, working hypotheses, testable conjectures and even (sometimes) speculative fictions. Likewise absent from Hawking’s account is philosophy’s gatekeeper role in spotting those instances where science strays over without due acknowledgement from one to another mode, or – as frequently happens nowadays – where certain evidential constraints are lifted and empirically informed rational conjecture gives way to pure fabulation.
Besides this, there are supposedly cutting-edge theories which turn out, on closer inspection, to unwittingly replicate bygone notions from the history of thought that have been criticised and eventually laid to rest. Hawking’s book puts forward two such theories. One is his linchpin ‘M-theory’ having to do with the multiple dimensions – eleven at the latest count – that are taken to constitute the ultimate reality beyond appearances despite our sensory perception being limited to the three-plus-one of our familiar spatio-temporal world. On this account there cannot be a single, comprehensive ‘Theory of Everything’ of the kind favoured by sanguine types like Steven Weinberg but we can hope to get a whole range of specially tailored, region-specific theories which between them point toward the nature and structure of ultimate reality. The other, closely related to that, is Hawking’s idea of ‘model-dependent realism’ as an approach that makes allowance (as per orthodox quantum mechanics) for the effect of observation on the item observed but which nonetheless retains an adequate respect for the objectivity of scientific truth.
Here Hawking’s argument shows all the signs of a rudderless drifting between various positions adopted by different philosophers from Kant to the present. He spends a lot of time on what seems to be a largely unwitting rehash of episodes in the history of idealist or crypto-idealist thought, episodes which have cast a long shadow over post-Kantian philosophy of science. That shadow still lies heavy on Hawking’s two central ideas of M-theory and model-dependent realism. They both look set to re-open the old Kantian split between a ‘noumenal’ ultimate reality forever beyond human knowledge and a realm of ‘phenomenal’ appearances to which we are confined by the fact of our perceptual and cognitive limits. So if Hawking is right to charge some philosophers with a culpable ignorance of science then there is room for a polite but firm tu quoque, whether phrased in terms of pots calling kettles black or boots on other feet. For it is equally the case that hostility or indifference toward philosophy can sometimes lead scientists, especially those with a strong speculative bent, not only to reinvent the wheel but to produce wheels that don’t track straight and consequently tend to upset the vehicle.
A firmer grasp of these issues as discussed by philosophers during the past few decades might have moderated Hawking’s scorn and also sharpened his critical focus on certain aspects of current theoretical physics. My point is not so much that a strong dose of philosophic realism might have clipped those speculative wings but rather that philosophers are well practised in steering a course through such choppy waters, or in managing to navigate despite all the swirls induced by a confluence of science, metaphysics, and far-out conjecture. After all, physics has increasingly come to rely on just the kind of disciplined speculative thinking that philosophers have typically invented, developed, and then criticised when they overstepped the limits of rationally accountable conjecture. Such are those ‘armchair’ thought-experiments that claim to establish some substantive, i.e., non-trivial thesis concerning the nature of the physical world by means of a rigorous thinking-through that establishes the truth (or, just as often, the demonstrable falsehood) of any statement affirming or denying it.
No doubt there is room to debate whether these are really (and remarkably) instances of scientific discovery achieved through an exercise of a priori reasoning or whether they amount, as sceptics would have it, to a species of disguised tautology. However there are just too many impressive examples in the history of science – from Galileo’s marvellous thought-experiment showing that Aristotle must have been wrong about falling bodies to a number of crucial quantum-related results – for anyone to argue convincingly that results obtained in the ‘laboratory of the mind’ can only impress philosophers keen to defend their patch. Indeed, there is a sense in which the scientific enterprise stands or falls on the validity of counterfactual-conditional reasoning, that is to say, reasoning from what necessarily would be the case should certain conditions obtain or certain hypotheses hold. In its negative guise, this kind of thinking involves reasoning to what would have been the outcome if certain causally or materially relevant factors had not been operative in some given instance. Hawking constantly relies on such philosophical principles in order to present and justify his claims about the current and likely future course of developments in physics. Of course he is very welcome to them but he might do better to acknowledge their source in ways of thinking and protocols of valid argumentation that involve distinctly philosophical as well as scientific grounds.
This brings us back to the point likely to provoke the most resistance from those scientists – chiefly theoretical physicists – who actually have the most to gain from any assertion of philosophy’s claim to a hearing in such matters. It is that scientists tend to go astray when they start to speculate on issues that exceed not only the current-best observational evidence but even the scope of what is presently conceivable in terms of testability. To speak plainly: one useful job for the philosopher of science is to sort out the errors and confusions that scientists – especially theoretical physicists – sometimes fall into when they give free rein to a speculative turn of mind. My book Quantum Theory and the Flight from Realism found numerous cases to illustrate the point in the statements of quantum theorists all the way from Niels Bohr – a pioneering figure but a leading source of metaphysical mystification – to the current advocates (Hawking among them) of a many-worlds or ‘multiverse’ theory. To adapt the economist Keynes’ famous saying: those scientists who claim to have no use for philosophy are most likely in the grip of a bad old philosophy or an insufficiently thought-out new one that they don’t fully acknowledge.
There is a large supply of present-day (quasi-)scientific thinking at the more – let us say – creative or imaginative end of the scale that falls into just this hybrid category of high-flown metaphysical conjecture tenuously linked to certain puzzling, contested, or at any rate far from decisive empirical results. Nor is it mere hubris for philosophers to claim a special competence in judging when thought has crossed that line from the realm of rational, scientifically informed but so far unproven conjecture to the realm of unanchored speculation or outright science fiction fantasy. One has only to pick up a copy of New Scientist or Scientific American to see how much of the latest thinking inhabits that shadowy border-zone where the three intermingle in ways that a suitably trained philosopher would be best equipped to point out. Nowhere is this more evident than in the past hundred years of debate on and around the seemingly paradoxical implications of quantum mechanics. Those paradoxes include wave/particle dualism, the so-called ‘collapse of the wave-packet’, the observer’s role in causing or inducing said collapse, and – above all since it appears the only way of reconciling these phenomena within anything like a coherent ontology – faster-than-light interaction between widely separated particles.
I shall risk the charge of shameless self-advertisement and suggest that readers take a look at my book for the case that these are pseudo-dilemmas brought about by a mixture of shaky evidence, dubious reasoning on it, fanciful extrapolation, and a flat refusal to entertain alternative theories (such as that of the physicist David Bohm) which considerably lighten the burden of unresolved paradox. At any rate we are better off trusting to the kinds of advice supplied by scientifically-informed philosophers with a well-developed sense of how speculative thinking can sometimes go off the rails than the kinds – including the advice ‘let’s put a stop to philosophy’ – issued by philosophically under-informed scientists."
Read the entire free article written by philosopher Christopher Norris by clicking here.