Why Us?: How Science Rediscovered the Mystery of Ourselves

This brings us to the second of the dual meanings of ‘wonder’ suggested at the close of the preceding chapter, to ‘wonder why’, which, as the Greek philosopher Plato observed, ‘is the beginning of all knowledge’.

‘The scientist does not study nature because it is useful to do so,’ wrote the nineteenth-century French mathematician Henri Poincaré. ‘He studies it because he takes pleasure in it; and he takes pleasure in it because it is beautiful. If nature were not beautiful, it would not be worth knowing, and life would not be worth living … I mean the intimate beauty which comes from the harmonious order of its parts and which a pure intelligence can grasp.’

The greatest (probably) of all scientists, Isaac Newton, seeking to comprehend that ‘harmonious order of parts’, would discover the fundamental laws of gravity and motion, that, being Universal (they hold throughout the universe), Absolute (unchallengeable), Eternal (holding for all time) and Omnipotent (all-powerful), he inferred, offered a glimpse into the mind of the Creator. Newton captured this dual meaning of wonder, to ‘wonder at’ and to ‘wonder why’, in his famous confession that the most he could hope to achieve was to illuminate the workings of some small part of that sublime world: ‘I do not know what I may appear to the world,’ he wrote, ‘but to myself I seem to have been only like a boy playing on the sea shore, diverting myself now and then, finding a smoother pebble than ordinary, whilst the great ocean of truth lay all undiscovered before me.’

The wonders of the world are so pervasive that to the seemingly less sophisticated minds of earlier ages (such as Newton’s) they were best understood as ‘natural miracles’. To be sure, the undeviating and punctual sun, the cycle of life, the infinite variety of living things, their interconnectedness to each other, these are all part of nature, and are faithful to its laws. They are ‘natural’. But the totality of it all, its beauty and integrity and completeness, that ‘great undiscovered ocean of truth’, lie so far beyond the power of the human mind to properly comprehend, they might as well be ‘a miracle’. Thus science and religion were cheerfully reconciled, the scientist seeing his task as a holy calling, where Robert Boyle, the founder of modern physics, would perceive his role as ‘a priest in the temple of nature’.

This is scarcely the modern view. Most people, of course, acknowledge the beauty and complexity of the world and find it admirable, even uplifting – but you could search in vain for a textbook of biology or zoology, astronomy or botany, or indeed of any scientific discipline, which even hints that there is something astonishing, extraordinary, let alone ‘miraculous’, about its subject. Science no longer ‘does’ wonder, which is more readily associated nowadays with the incurious mysticism and incense of the New Age. Science prefers to cultivate an aura of intellectual neutrality, the better to convey its disinterested objectivity, its commitment to the ‘truth’. Hence the highly technical, and to the outsider often impenetrable, prose of its texts and learned journals, from which any sense of wonder is rigorously excluded.

There are, as will be seen, several important reasons for this modern-day lack of astonishment, but the most important is undoubtedly the general perception that science, since Newton’s time, has revealed those ‘natural miracles’ to have a distinctly non-miraculous, materialist explanation – culminating in that firestorm of scientific discovery of the past fifty years, which has integrated into one coherent narrative the entire history of the universe from its origins to the present day. To be sure, science may not capture the beauty and connectedness of it all, the ‘sublime spirit that rolls through all things’, but this is more than compensated for by the sheer drama and excitement of the events it has so convincingly described.

The scale of that intellectual achievement is so great that there might seem little room any more for the ‘natural miracles’ of an earlier age, or to ‘wonder’ whether there might after all be more than we can know. It would certainly require a truly Olympian perspective, capable of surveying the vast landscape of science, to recognise where and what the limits to its knowledge might be – and that would seem an impossibility. Yet it is not quite so, for while that landscape is indeed vast, and far beyond the comprehending of any individual, it is nonetheless sustained by three great unifying phenomena that impose order on the world – which on examination can tell us something very profound about science and the limits of its materialist explanations.

It is fruitless – always has been, always will be – to pose that most elementary of all questions: ‘Why is there something rather than nothing?’ The same however does not apply to the second and supplementary question: ‘Why, given there is something, are both the physical universe (and all that it contains) and all life (in its infinite diversity) so ordered?’ They should not be, for anything left to itself will tend towards chaos and disorder, as fires burn out and clocks run down – unless countered by a compensating force imposing order, restituting lost energy.

There are (to put it simply) three ‘forces for order’: first the force of gravity, as discovered by Sir Isaac Newton, the glue that binds the universe together; next the all-powerful genes strung out along the Double Helix, imposing the order of form, the shape, characteristics and attibutes unique to each of the millions of species of living things; and thirdly the human mind, that imposes the order of understanding on the natural world and our place within it. These three forces control or sustain all (or virtually all) phenomena in the universe, and stand proxy for the ‘vast landscape’ of science. Thus, if they are knowable scientifically as belonging to that materialist, second-order reality of the physics and chemistry of matter (where water is a combination of two molecules of hydrogen and one of oxygen), then by definition there is nothing in theory that science cannot know. But if they are not so knowable, one can only infer that they exert their effects through some other force that lies beyond the range of science and its methods to detect. We start with Sir Isaac Newton’s theory of gravity.

Isaac Newton, born in 1642 into a semi-literate sheep-farming family in rural Lincolnshire, was one of the tiny handful of supreme geniuses who have shaped the categories of human knowledge. From the time of Aristotle onwards, and for the best part of two thousand years, the regularity and order of the physical world was as it was because it was divinely ordained to be so: the punctual and undeviating sun, the movement of the planets across the heavens, the passage of the seasons and apples falling from trees. Newton’s genius was to realise that these and numerous other aspects of the physical world were all linked together by the hidden force of gravity.

Soon after graduating at the age of twenty-three from Cambridge University, Newton was compelled by an epidemic of bubonic plague to return to his home in Lincolnshire. There, over a period of just two years, he made a series of scientific discoveries that would not be equalled till Einstein, almost 250 years later. These included the nature of light and the mathematical method of differential calculus, with which it is possible to calculate the movement of the planets in their orbit. Newton’s most famous insight came when, sitting in his garden, he saw an apple fall from a tree. He ‘wondered’ whether the force of the earth’s gravity pulling the apple to the ground might reach still further, and hold the moon in its orbit around the earth.

Newton’s friend Dr William Stukeley would later record his reminiscences of that great moment.

After dinner, the weather being warm, we went into the garden and drank tea, under the shade of some apple trees, only he and myself. Amidst other discourse, he told me he was just in the same situation as when, formerly, the notion of gravitation came into his mind. It was occasioned by the fall of an apple, as he sat in a contemplative mood. Why should that apple always descend perpendicularly to the ground, thought he to himself? Why should it not go sideways or upwards, but constantly to the earth’s centre? Assuredly, the reason is, that the earth draws it. There must be a drawing power in matter … and if matter thus draws matter, it … must extend itself through the universe.

Newton’s ‘notion of gravitation’, of ‘matter drawing on matter’, would resolve the greatest conundrum of the movement of those heavenly bodies, why they remained in their stately orbits (the moon around the earth, the earth around the sun) rather than, as they should by rights, being impelled by their centrifugal force into the far depths of outer space. Newton, being a mathematical genius, calculated the strength of that countervailing force of gravity, showing it to be determined by the masses of the moon and earth, earth and sun respectively, multiplied together and divided by the distance between them, and so too throughout the entire universe. By the time Newton published his epic three-volume Principia Mathematica in 1697, describing the theory of gravity and the three laws of motion, he had transformed the divinely ordained physical world into which he was born into one governed by absolute and unchallengeable universal laws known to man, where everything was linked to everything else in a never-ending series of causes – all the way into the past and indefinitely into the future.

From the beginning, the force of gravity at the moment of the Big Bang imposed the necessary order on those billions of elementary particles, concentrating them into massive, heat-generating stars. Several thousand millions of years later, the same force of gravity would impose order on our solar system, concentrating 99 per cent of its matter within the sun to generate the prodigious amounts of energy, heat and light that would allow the emergence of life on earth. And anticipating the future? Newton’s friend, the Astronomer Royal Edmond Halley, used Newton’s laws to work out the elliptical orbit of the comet that bears his name and so predict its seventy-six-year cycle of return. Three hundred years later, NASA scientists would use those same laws to plot the trajectory of the first manned space flight to the moon. Newton’s laws can even predict when it will all end – in five thousand million years’ time (or thereabouts), when the prodigious energy generated by our sun will be exhausted, and our earth will perish.

As time has passed, so the explanatory power of Newton’s laws of gravity has grown ever wider, to touch virtually every aspect of human experience: the movement of the sun and stars (obviously), the waxing and waning of the moon, the ebb and flow of the tides, the contrasting climates of the Arctic Circle and the sand-swept desert, the cycle of the seasons, rain falling on the ground, the shape of mountains sculpted by the movement of glaciers, the flow of rivers towards the sea, the size of living things from whale to flea and indeed ourselves – for we could not be any bigger than we are without encountering the hazard, posed by gravity, of falling over.

Newton’s laws epitomise, to the highest degree, the explanatory power of science, through which for the first time we humans could comprehend the workings of that vast universe to which we belong. But, and it is a most extraordinary thing, three hundred years on, the means by which the powerful, invisible glue of gravity imposes order on the universe remains quite unknown. Consider, by analogy, a child whirling a ball attached to a string around its head, just as gravity holds the earth in its perpetual orbit around the sun. Here, the string (like gravity) counteracts the centrifugal force that would hurtle the ball (the earth) into a distant tree. But there is no string. Newton himself was only too well aware that there had to be some physical means by which gravity must exert its influence over hundreds, thousands, of millions of miles of empty space. It was, he wrote, ‘an absurdity that no thinking man can ever fall into’ to suppose that gravity ‘could act at a distance through a vacuum without the mediation of anything else, by which that action and force may be conveyed’.

Perhaps, he speculated, space was suffused by an invisible ‘ether’ composed of very small particles that repelled one another and by which the sun could hold the earth in its orbit – though this would mean that over a very long period the movement of the planets would gradually slow down through the effects of friction. But in 1887 an American physicist, Albert Michelson, discovered that there was no ‘ether’. Space is well named – it is empty. Put another way, Newton’s theory encompasses the profound contradiction of gravity being both an immensely powerful force imposing order on the matter of the universe, linking its history all the way back to the beginning and anticipating its end, yet itself being non-material. This extraordinary property of gravitation requires some sort of context, by contrasting it with, for example, that equally potent invisible ‘force’ electricity, which at the touch of a switch floods the room with light. But whereas electricity is a ‘material’ force – the vibration of electrons passing along a copper wire – gravity exerts its effects across billions of miles of empty space, through a vacuum of nothingness.

Newton’s theory stands (for all time), but has been modified in two directions. First, in 1915, Albert Einstein in his General Theory of Relativity reformulated the concept of gravity to allow for space to be ‘elastic’, so that a star like our sun could curve and stretch the space around it – and the bigger the star, the greater the effect. Matter, Einstein showed, warps space. This takes care of the more bizarre phenomena in the universe, such as ‘black holes’, that capture even the weightless particles of light – but for all that the profound Newtonian mystery of how gravity exerts its force through the vacuum of space remains unresolved.

Next, it has emerged that Newton’s gravitational force is not alone, being just one of four (similarly non-material) forces, including those that bind together the atomic particles of protons and neutrons – whose disruption generates the prodigious energy of an atomic explosion. In the twentieth century, the conundrum of the non-materiality of those gravitational forces was compounded when it emerged that their strength is precisely tuned to permit the consequent emergence of life and ourselves. If the force they exert were, for example, ever so slightly stronger, then stars (like our sun) would attract more matter from interstellar space, and being so much bigger would burn much more rapidly and intensely – just as a large bonfire outburns a smaller one. They would then exhaust themselves in as little as ten million years, instead of the several billion necessary for life to ‘get going’. If, contrariwise, the force of gravity were ever so slightly weaker, the reverse would apply, and the sun and stars would not be big enough to generate those prodigious amounts of heat and energy. The sky would be empty at night, and once again we humans would never have been around to appreciate it. It is, of course, very difficult to convey just how precise those forces necessary for the creation of the universe (and the subsequent emergence of life on planet earth) had to be, but physicist John Polkinghorne estimates their fine tuning had to be accurate to within one part in a trillion trillion (and several trillion more), a figure greater by far than all the particles in the universe – a degree of accuracy, it is estimated, equivalent to hitting a target an inch wide on the other side of the universe.

Isaac Newton’s theory of gravity is the most elegant idea in the history of science. Nothing touches its combination of pure simplicity, readily understandable by a class of ten-year-olds, and all-encompassing explanatory power. His contemporaries were dazzled that so elementary a mathematical formula could account for so much – prompting the poet Alexander Pope to propose as his epitaph in Westminster Abbey:

Nature and nature’s laws lay hidden in night

God said Let Newton be! And all was light.

Still, Newton’s gravitational force, imposing ‘order’ on the physical universe, clearly fails the test of scientific ‘knowability’, for while we can fully comprehend all its consequences we are ‘left with that absurdity that no thinking man can ever fall into’ of having to suppose that a non-material force can ‘act at a distance’ across millions of miles of empty space without the mediation of anything by which that action and force may be conveyed. Thus, ironically, this most scientific of theories, grounded in the observation of the movements of the planets expressed in mathematical form, subverts the scientific or materialist view which holds that everything must ultimately be explicable in terms of its material properties alone.

We turn now to the living world of plants, insects, fishes, birds and ourselves, which is billions upon billions upon billions of times more complex than Newton’s non-living, physical universe. Hence, the two forces that impose order on that world, the Double Helix imposing the order of form on living things, and the human brain and its mind imposing the order of understanding, will be profounder than the glue of gravity by similar orders of magnitude. We might anticipate that these two further forces of order will, like Newton’s theory of gravity, similarly prove to be non-material, and therefore fail the test of scientific knowability. But to ‘get there’ we must first come to grips with how we have come to suppose otherwise, and specifically how in the mid-nineteenth century Darwin’s grand evolutionary theory, as set out in the twin texts of On the Origin of Species and The Descent of Man, offered an apparently all-encompassing and exclusively materialist explanation for the phenomena of life.

4 The (Evolutionary) ‘Reason forEverything’: Certainty

‘There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one … from so simple a beginning endless forms most beautiful and most wonderful have been evolved.’

Charles Darwin, On the Origin of Species (1859)

Charles Darwin, while a theology student at Cambridge University, developed a passion for beetles. ‘Nothing gave me so much pleasure,’ he would write in his autobiography, recalling how, ‘as proof of my zeal’:

One day, on tearing off some old bark I saw two rare beetles and seized one in each hand; then I saw a third and new kind, which I could not bear to lose, so I put the one which I held in my right hand into my mouth. But alas! It ejected some intensely acrid fluid that burnt my tongue so I was forced to spit it out and so it was lost.

Darwin’s zeal for beetles was quite unexceptional, for he was born into the Golden Age of Natural History, when the wonders of nature as revealed by science gripped the public imagination with an extraordinary intensity, while being also the most tangible evidence of a divinely ordained world. ‘The naturalist … sees the beautiful connection that subsists throughout the whole scheme of animated nature,’ observed the editor of the Zoological Journal of London. ‘He traces … the mutual depending that convinces him nothing is made in vain.’

There seemed no limit to the new forms of ‘animated nature’ just waiting to be discovered. In 1771 the famed maritime explorer James Cook had returned from his epic three-year circumnavigation of the world ‘laden with the greatest treasure of natural history that ever was brought into any country at one time’: no fewer than 1,400 new plant species, more than a thousand new species of animals, two hundred fish and assorted molluscs, insects and marine creatures. For his friend the anatomist John Hunter, waiting for him as his ship anchored off Deal harbour, Cook had several unusual specimens to add to his famous collection: a striped polecat from the Cape of Good Hope, part of a giant squid, and a peculiar animal ‘as large as a greyhound, of mouse colour and very swift’, known in the Aboriginal dialect as a ‘kangooroo’.

The discovery of this exhilarating diversity of life extended beyond the living to the long-since extinct. For this, too, was the great period of geological discovery of the antiquity of the earth, the strata of whose rocks revealed fossilised bones and teeth so much larger than any previously encountered as to suggest that vast, fantastical creatures had roamed the surface of the earth millions of years before man.

The immediate fascination of natural history lay in the accurate description of that teeming variety of life, but beyond that there was every reason to suppose that comparing the anatomical structure and the behaviour of living organisms such as the polecat, squid and kangaroo would reveal the long-suspected hidden laws that link all ‘animated nature’ together. The search for those laws stretches back into antiquity, seeking first to explain the ‘vitality’ of the living, the heat, energy and movement that so readily distinguish it from the nonliving, and that depart so promptly at the moment of death. The subtler, yet related, question concerned the nature of ‘form’, those elusive qualities of pattern and order that so clearly distinguish polecat, squid and kangaroo from each other, and the tissues of which they are made – as readily as a grand palace is distinguished from a humble factory, and from the bricks and mortar of which they are constructed. But the elusive ‘form’ of polecat and squid, unlike that of the palace or the factory, has the further extraordinary property of remaining constant throughout their lives, even though the ‘bricks and mortar’ from which they are fashioned are being constantly replaced and renewed. From the first natural historian, Aristotle, onwards, it was presumed that some organising principle, some ‘formative impulse’, must both determine and ensure that constancy of form.

The presiding genius of natural history, Baron Georges Cuvier (1769–1832), director of the Musée d’Histoire Naturelle in Paris, proposed two laws of that ‘formative impulse’, the laws of similarity (homology) and correlation. First, homology. Cuvier inferred from a detailed study of the ten thousand specimens in his collection that the diverse forms of animals each concealed an underlying ‘unity of type’, all being variations on the same ‘blueprint’: the wings of bird and bat, the paddle of a porpoise, the horse’s legs and the human forearm were all constructed from the same bones, adapted to their ‘way of life’ – whether flying or swimming, running or grasping.

His second law, of ‘correlation’, asserted that the various parts of every animal, its skull, limbs, teeth, etc., were all ‘of a piece’, all correlated together, being so fashioned as to fulfil its way of life. Thus a carnivore, such as a lion or hyena, would have limbs strong enough to grasp its victim and muscular enough for hunting, jaws sufficiently powerful and teeth sharp enough to rip its flesh, and so on. ‘Every organised being forms a whole, a unique and perfect system, the parts of which mutually correspond and concur in the same definitive action,’ he wrote.

Cuvier maintained that these laws dictating the harmony of the parts of the ‘unique and perfect system’ were as precise as those of mathematics. He could not specify the biological forces behind them, but they were not merely some theoretical inference. Rather, they could be ‘put to the test’, allowing him, to the astonishment of all, to ‘restore to life’ those fantastical and long-extinct creatures from long ago, reconstructing from the assorted bones and teeth of their fossilised remains a ‘megatherium’, or ‘huge beast’, a creature resembling a giant sloth which would stand on two legs to graze on leaves. ‘Is not Cuvier the great poet of our era?’ enquired the novelist Honoré de Balzac. ‘Our immortal naturalist has reconstructed past worlds from a few bleached bones … discovered a Giant population from the footprints of a mammoth.’