Many in the academic community... have discovered a new form of anti-scientific rhetoric, sometimes called the ‘postmodern critique' of science. The most thorough whistle-blowing on this kind of thing is Paul Gross and Norman Levitt's splendid book, Higher Superstition: The Academic Left and its Quarrels with Science. The American anthropologist Matt Cartmill sums up the basic credo:
"Anybody who claims to have objective knowledge about anything is trying to control and dominate the rest of us... There are no objective facts. All supposed "facts" are contaminated with theories, and all theories are infested with moral and political doctrines... Therefore, when some guy in a lab coat tells you that such and such is an objective fact . . . he must have a political agenda up his starched white sleeve."
There are even a few, but very vocal, fifth columnists within science itself who hold exactly these views, and use them to waste the time of the rest of us.
Cartmill's thesis is that there is an unexpected and pernicious alliance between the know-nothing fundamentalist religious right, and the sophisticated academic left. A bizarre manifestation of the alliance is joint opposition to the theory of evolution. The opposition of the fundamentalists is obvious. That of the left is a compound of hostility to science in general, of ‘respect' for tribal creation myths, and various political agendas. Both these strange bedfellows share a concern for ‘human dignity' and take offence at treating humans as ‘animals'. Moreover, in Cartmill's words, both camps believe that the big truths about the world are moral truths. They view the universe in terms of good and evil, not truth and falsehood. The first question they ask about any supposed fact is whether it serves the cause of righteousness."
And there is a feminist angle, which saddens me, for I am sympathetic to true feminism.
"Instead of exhorting young women to prepare for a variety of technical subjects by studying science, logic, and mathematics, Women's Studies students are now being taught that logic is a tool of domination. . . the standard norms and methods of scientific inquiry are s**ist because they are incompatible with "women's ways of knowing." The authors of the prize-winning book with thistitle report that the majority of the women they interviewed fell into the category of ‘subjective knowers', characterized by a ‘pa**ionate rejection of science and scientists.' These ‘subjectivist' women see the methods of logic, an*lysis and abstraction as ‘alien territory belonging to men' and ‘value intuition as a safer and more fruitful approach to truth'." That was a quotation from the historian and philosopher of science Noretta Koertge, who is understandably worried about a subversion of feminism which could have a malign influence upon women's education. Indeed, there is an ugly, hectoring streak in this kind of thinking. Barbara Ehrenreich and Janet McIntosh witnessed a woman psychologist speaking at an interdisciplinary conference. Various members of the audience attacked her use of the . . . oppressive, s**ist, imperialist, and capitalist scientific method. The psychologist tried to defend science by pointing to its great discoveries – for example, DNA. The retort came back: "You believe in DNA?" Fortunately, there are still many intelligent young women prepared to enter a scientific career, and I should like to pay tribute to their courage in the face of such bullying intimidation.
I have come so far with scarcely a mention of Charles Darwin. His life spanned most of the nineteenth century, and he died with every right to be satisfied that he had cured humanity of its greatest and grandest illusion. Darwin brought life itself within the pale of the explicable. No longer a baffling mystery demanding supernatural explanation, life, with the complexity and elegance that defines it, grows and gradually emerges, by easily understood rules, from simple beginnings. Darwin's legacy to the twentieth century was to demystify the greatest mystery of all.
Legacy and Outlook
Would Darwin be pleased with our stewardship of that legacy, and with what we are now in a position to pa** to the twenty first century? I think he would feel an odd mixture of exhilaration and exasperation. Exhilaration at the detailed knowledge, the comprehensiveness of understanding, that science can now offer, and the polish with which his own theory is being brought to fulfilment. Exasperation at the ignorant suspicion of science, and the air-headed superstition, that still persist. Exasperation is too weak a word. Darwin might justifiably be saddened, given our huge advantages over himself and his contemporaries, at how little we seem to have done to deploy our superior knowledge in our culture. Late twentieth century civilisation, Darwin would be dismayed to note, though imbued and surrounded by the products and advantages of science, has yet to draw science into its sensibility. Is there even a sense in which we have slipped backwards since Darwin's co-discoverer, Alfred Russel Wallace wrote The Wonderful Century, a glowing scientific retrospective on his era? Perhaps there was undue complacency in turn-of-century science, about how much had been achieved and how little more advancement could be expected. William Thomson, First Lord Kelvin, President of the Royal Society, pioneered the transatlantic cable – symbol of Victorian progress – and also the second law of thermodynamics – C P Snow's litmus of scientific literacy. Kelvin is credited with the following three confident predictions: ‘Radio has no future.' ‘Heavier than air flying machines are impossible.' ‘X-rays will prove to be a hoax.' Kelvin also gave Darwin a lot of grief by ‘proving,' using all the prestige of the senior science of physics, that the sun was too young to have allowed time for evolution. Kelvin, in effect, said, "Physics argues against evolution, so your biology must be wrong." Darwin could have retorted: "Biology shows that evolution is a fact, so your physics must be wrong." Instead, he bowed to the prevailing a**umption that physics automatically trumps biology, and fretted. Twentieth century physics, of course, showed Kelvin wrong by powers of ten. But Darwin did not live to see his vindication, and he never had the confidence to tell the senior physicist of his day where to get off. In my attacks on millenarial superstition, I must beware of Kelvinian over-confidence. Undoubtedly there is much that we still don't know. Part of our legacy to the 21st century must be unansweredquestions, and some of them are big ones. The science of any age must prepare to be superseded. It would be arrogant and rash to claim our present knowledge as all there is to know. Today's commonplaces, such as mobile telephones, would have seemed to previous ages pure magic. And that should be our warning. Arthur C. Clarke, distinguished novelist and evangelist for the limitless power of science, has said, ‘Any sufficiently advanced technology is indistinguishable from magic.' This is Clarke's Third Law.
Maybe, some day in the future, physicists will fully understand gravity, and build an anti-gravity machine. Levitating people may one day become as commonplace to our descendants as jet planes are to us. So, if someone claims to have witnessed a magic carpet zooming over the minarets, should we believe him, on the grounds that those of our ancestors who doubted the possibility of radio turned out to be wrong? No, of course not. But why not? Clarke's Third Law doesn't work in reverse. Given that ‘Any sufficiently advanced technology is indistinguishable from magic' it does not follow that ‘Any magical claim that anybody may make at any time is indistinguishable from a technological advance that will come some time in the future.' Yes, there been occasions when authoritative sceptics have come away with egg on their pontificating faces. But a far greater number of magical claims have been made and never vindicated. A few things that would surprise us today will come true in the future. But lots and lots of things will not come true in the future. History suggests that the very surprising things that do come true are in a minority. The trick is to sort them out from the rubbish – from claims that will forever remain in the realm of fiction and magic.
It is right that, at the end of our century, we should show the humility that Kelvin, at the end of his, did not. But it is also right to acknowledge all that we have learned during the past hundred years. The digital century was the best I could come up with, as a single theme. But it covers only a fraction of what 20th century science will bequeath. We now know, as Darwin and Kelvin did not, how old the world is. About 4.6 billion years. We understand – what Alfred Wegener was ridiculed for suggesting – that the shape of geography has not always been the same. South America not only looks as if it might jigsaw neatly under the bulge of Africa. It once did exactly that, until they split apart some 125 million years ago. Madagascar once touched Africa on one side and India on the other. That was before India set off across the widening ocean and crashed into China to raise the Himalayas. The map of the world's continents has a time dimension, and we who are privileged to live in the Plate Tectonic Age know exactly how it haschanged, when, and why.
We know roughly how old the universe is, and, indeed, that it has an age, which is the same as the age of time itself, and less than twenty billion years. Having begun as a singularity with huge ma** and temperature and very small volume, the universe has been expanding ever since. The 21st century will probably settle the question whether the expansion is to go on for ever, or go into reverse. The matter in the cosmos is not h*mogeneous, but is gathered into some hundred billion galaxies, each averaging a hundred billion stars. We can read the composition of any star in some detail, by spreading its light in a glorified rainbow. Among the stars, our sun is generally unremarkable. It is unremarkable, too, in having planets in orbit, as we know from detecting tiny rhythmic shifts in the spectrums of stars. There is no direct evidence that any other planets house life. If they do, such inhabited islands may be so scattered as to make it unlikely that one will ever encounter another.
We know in some detail the principles governing the evolution of our own island of life. It is a fair bet that the most fundamental principle – Darwinian natural selection – underlies, in some form, other islands of life, if any there be. We know that our kind of life is built of cells, where a cell is either a bacterium or a colony of bacteria. The detailed mechanics of our kind of life depend upon the near-infinite variety of shapes a**umed by a special cla** of molecules called proteins. We know that those all-important three-dimensional shapes are exactly specified by a one-dimensional code, the genetic code, carried by DNA molecules which are replicated through geological time. We understand why there are so many different species, although we don't know how many. We cannot predict in detail how evolution will go in the future, but we can predict the general patterns that are to be expected.
Among the unsolved problems we shall bequeath to our successors, physicists such as Steven Weinberg will point to their Dreams of a Final Theory, otherwise known as the Grand Universal Theory, or Theory of Everything. Theorists differ about whether it will ever be attained. Those who think it will would probably date this scientific epiphany somewhere in the 21st century. Physicists famously resort to religious language when discussing such deep matters. Some of them really mean it. The others are at risk of being taken literally, when really they intend no more than I do when I say "God knows" to mean that I don't.
Biologists will reach their grail of writing down the human genome, early in the next century. They will then discover that it is not so final as some once hoped. The human embryo project – working out how the genes interact with their environments, including each other, to build a body – may take at least as long to complete. But it too will probably be finished during the 21st century, and artificial wombs built, if these should be thought desirable.
I am less confident about what is for me, as for most biologists, the outstanding scientific problem that remains: the question of how the human brain works, especially the nature of subjective consciousness. The last decade of this century has seen a flurry of big guns take aim at it, including Francis Crick no less, and Daniel Dennett, Steven Pinker and Sir Roger Penrose. It is a big, profound problem, worthy of minds like these. Obviously I have no solution. If I had, I'd deserve a Nobel Prize. It isn't even clear what kind of a problem it is, and therefore what kind of a brilliant idea would constitute a solution. Some people think the problem of consciousness an illusion: there's nobody home, and no problem to be solved. But before Darwin solved the riddle of life's provenance, in the last century, I don't think anybody had clearly posed what sort of a problem it was. It was only after Darwin had solved it that most people realised what it had been in the first place. I do not know whether consciousness will prove to be a big problem, solved by a genius; or will fritter unsatisfactorily away into a series of small problems and non problems.
I am by no means confident that the 21st century will solve the human mind. But if it does, there may be an additional byproduct. Our successors may then be in a position to understand the paradox of 20th century science:- On the one hand our century arguably added as much new knowledge to the human store as all previous centuries put together; while on the other hand the 20th century ended with approximately the same level of supernatural credulity as the 19th, and rather more outright hostility to science. With hope, if not with confidence, I look forward to the 21st century and what it may teach us.