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  Theologians worry about the problems of suffering and evil, to the extent that they have even invented a name, ‘theodicy’ (literally, ‘justice of God’), for the enterprise of trying to reconcile it with the presumed beneficence of God. Evolutionary biologists see no problem, because evil and suffering don’t count for anything, one way or the other, in the calculus of gene survival. Nevertheless, we do need to consider the problem of pain. Where, on the evolutionary view, does it come from?

  Pain, like everything else about life, we presume, is a Darwinian device, which functions to improve the sufferer’s survival. Brains are built with a rule of thumb such as, ‘If you experience the sensation of pain, stop whatever you are doing and don’t do it again.’ It remains a matter for interesting discussion why it has to be so damned painful. Theoretically, you’d think, the equivalent of a little red flag could painlessly be raised somewhere in the brain, whenever the animal does something that damages it: picks up a red-hot cinder, perhaps. An imperative admonition, ‘Don’t do that again!’ or a painless change in the wiring diagram of the brain such that, as a matter of fact, the animal doesn’t do it again, would seem, on the face of it, enough. Why the searing agony, an agony that can last for days, and from which the memory may never shake itself free? Perhaps grappling with this question is evolutionary theory’s own version of theodicy. Why so painful? What’s wrong with the little red flag?

  I don’t have a decisive answer. One intriguing possibility is this. What if the brain is subject to opposing desires and impulses, and there is some kind of internal tussle between them? Subjectively, we know the feeling well. We may be in a conflict between, say, hunger and a desire to be slim. Or we may be in a conflict between anger and fear. Or between sexual desire and a shy fear of rejection, or a conscience that urges fidelity. We can literally feel the tug of war within us, as our conflicting desires battle it out. Now, back to pain and its possible superiority over a ‘red flag’. Just as the desire to be slim can over-rule hunger, it is clearly possible to over-rule the desire to escape pain. Torture victims may succumb eventually, but they often go through a phase of enduring considerable pain rather than, say, betray their comrades or their country or their ideology. In so far as natural selection can be said to ‘want’ anything, natural selection doesn’t want individuals to sacrifice themselves for the love of a country, or for the sake of an ideology or a party or a group or a species. Natural selection is ‘against’ individuals over-ruling the warning sensations of pain. Natural selection ‘wants’ us to survive, or more specifically, to reproduce, and be blowed to country, ideology or their non-human equivalents. As far as natural selection is concerned, little red flags will be favoured only if they are never over-ruled.

  Now, despite philosophical difficulties, I think that instances where pain was over-ruled for non-Darwinian reasons – reasons of loyalty to country, ideology, etc. – would be more frequent if we had a ‘red flag’ in the brain rather than real, full-on, intolerable pain. Suppose genetic mutants arose who could not feel the excruciating agony of pain but relied upon a ‘red flag’ system to keep them away from bodily damage. It would be so easy for them to resist torture, they’d promptly be recruited as spies. Except that it would be so easy to recruit agents prepared to bear torture that torture would simply stop being used as a method of extortion. But, in a wild state, would such pain-free, red-flag mutants survive better than rival individuals whose brains do pain in earnest? Would they survive to pass on the genes for red-flag pain substitutes? Even setting aside the special circumstance of torture, and the special circumstances of loyalty to ideologies, I think we can see that the answer might be no. And we can imagine non-human equivalents.

  As a matter of interest, there are aberrant individuals who cannot feel pain, and they usually come to a bad end. ‘Congenital insensitivity to pain with anhidrosis’ (CIPA) is a rare genetic abnormality in which the patient lacks pain receptor cells in the skin (and also – that’s the ‘anhidrosis’ – doesn’t sweat). Admittedly, CIPA patients don’t have a built-in ‘red flag’ system to compensate for the breakdown of the pain system, but you’d think they could be taught to be cognitively aware of the need to avoid bodily damage – a learned red flag system. At all events, CIPA patients succumb to a variety of unpleasant consequences of their inability to feel pain, including burns, breakages, multiple scars, infections, untreated appendicitis and scratches to the eyeballs. More unexpectedly, they also suffer serious damage to their joints because, unlike the rest of us, they don’t shift their posture when they have been sitting or lying in one position for a long time. Some patients set timers to remind themselves to change position frequently during the day.

  Even if a ‘red flag’ system in the brain could be made effective, there seems to be no reason why natural selection would positively favour it over a real pain system just because it is less unpleasant. Unlike our hypothetically beneficent designer, natural selection is indifferent to the intensity of suffering – except in so far as it affects survival and reproduction. And, just as we should expect if the survival of the fittest, rather than design, underlies the world of nature, the world of nature seems to take no steps at all to reduce the sum total of suffering. Stephen Jay Gould reflected on such matters in a nice essay on ‘Nonmoral nature’. I learned from it that Darwin’s famous revulsion at the Ichneumonidae, which I quoted at the end of the previous chapter, was far from unique among Victorian thinkers.

  Ichneumon wasps, with their habit of paralysing but not killing their victim, before laying an egg in it with the promise of a larva gnawing it hollow from within, and the cruelty of nature generally, were major preoccupations of Victorian theodicy. It’s easy to see why. The female wasps lay their eggs in live insect prey, such as caterpillars, but not before carefully seeking out with their sting each nerve ganglion in turn, in such a way that the prey is paralysed, but still stays alive. It must be kept alive to provide fresh meat for the growing wasp larva feeding inside. And the larva, for its part, takes care to eat the internal organs in a judicious order. It begins by taking out the fat bodies and digestive organs, leaving the vital heart and nervous system till last – they are necessary, you see, to keep the caterpillar alive. As Darwin so poignantly wondered, what kind of beneficent designer would have dreamed that up? I don’t know whether caterpillars can feel pain. I devoutly hope not. But what I do know is that natural selection would in any case take no steps to dull their pain, if the job could be accomplished more economically by simply paralysing their movements.

  Gould quotes the Reverend William Buckland, a leading nineteenth-century geologist, who found consolation in the optimistic spin that he managed to confer on the suffering caused by carnivores:

  The appointment of death by the agency of carnivora, as the ordinary termination of animal existence, appears therefore in its main results to be a dispensation of benevolence; it deducts much from the aggregate amount of the pain of universal death; it abridges, and almost annihilates, throughout the brute creation, the misery of disease, and accidental injuries, and lingering decay; and imposes such salutary restraint upon excessive increase of numbers, that the supply of food maintains perpetually a due ratio to the demand. The result is, that the surface of the land and depths of the waters are ever crowded with myriads of animated beings, the pleasures of whose life are coextensive with its duration; and which throughout the little day of existence that is allotted to them, fulfill with joy the functions for which they were created.

  Well, isn’t that nice for them!

  * ‘In the army, we has three kinds of trees: fir, poplar, and bushy top.’

  * An oxymoron if ever there was one.

  * Two hikers are pursued by a bear. One hiker runs away, the other stops to put on his running shoes. ‘Are you mad? Even with running shoes, you can’t outrun a grizzly.’ ‘No, but I can outrun you.’

  * Or she. The particular case of lions is complicated by the fact that females do most of the hunting, b
ut males tend to get ‘the lion’s share’ in any case. Don’t get hung up on ‘lions’ in my hypothetical example. Think of a generalized predator species, and imagine ‘prudent’ individuals who refrain from over-hunting, and ‘imprudent’ individuals who break away from the agreement.

  † Loose talk about Darwinian adaptation frequently founders on the fallacious assumption (not made explicit, and the more pernicious in consequence) that evolution has foresight. Sydney Brenner, hero of the Caenorhabditis section of Chapter 8, has a sardonic wit to match his scientific brilliance. I once heard him lampoon the ‘evolutionary foresight’ fallacy by imagining a species in the Cambrian that retained in its gene pool an otherwise useless protein, because ‘It might come in handy in the Cretaceous.’

  CHAPTER 13

  THERE IS GRANDEUR IN THIS VIEW OF LIFE

  UNLIKE his evolutionist grandfather Erasmus, whose scientific verse was (somewhat surprisingly, I have to say) admired by Wordsworth and Coleridge, Charles Darwin was not known as a poet, but he produced a lyrical crescendo in the last paragraph of On the Origin of Species.

  Thus, from the war of nature, from famine and death,* the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

  There’s a lot packed into this famous peroration, and I want to sign off by taking it line by line.

  ‘FROM THE WAR OF NATURE, FROM FAMINE AND DEATH’

  Clear-headed as ever, Darwin recognized the moral paradox at the heart of his great theory. He didn’t mince words – but he offered the mitigating reflection that nature has no evil intentions. Things simply follow from ‘laws acting all around us’, to quote an earlier sentence from the same paragraph. He had said something similar at the end of Chapter 7 of The Origin:

  it may not be a logical deduction, but to my imagination it is far more satisfactory to look at such instincts as the young cuckoo ejecting its foster-brothers, – ants making slaves, – the larvae of ichneumonidae feeding within the live bodies of caterpillars, – not as specially endowed or created instincts, but as small consequences of one general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.

  I’ve already mentioned Darwin’s revulsion – widely shared by his contemporaries – in the face of the female ichneumon wasp’s habit of stinging its victim to paralyse but not kill it, thereby keeping the meat fresh for its larva as it eats the live prey from within. Darwin, you’ll remember, couldn’t persuade himself that a beneficent creator would conceive such a habit. But with natural selection in the driving seat, all becomes clear, understandable and sensible. Natural selection cares naught for any comfort. Why should it? For something to happen in nature, the only requirement is that the same happening in ancestral times assisted the survival of the genes promoting it. Gene survival is a sufficient explanation for the cruelty of wasps and the callous indifference of all nature: sufficient – and satisfying to the intellect if not to human compassion.

  Yes, there is grandeur in this view of life, and even a kind of grandeur in nature’s serene indifference to the suffering that inexorably follows in the wake of its guiding principle, survival of the fittest. Theologians may here wince at this echo of a familiar ploy in theodicy, in which suffering is seen as an inevitable correlate of free will. Biologists, for their part, will find ‘inexorably’ by no means too strong when they reflect – perhaps along the lines of my ‘red flag’ meditation of the previous chapter – on the biological function of the capacity to suffer. If animals aren’t suffering, somebody isn’t working hard enough at the business of gene survival.

  Scientists are human, and they are as entitled as anyone to revile cruelty and abhor suffering. But good scientists like Darwin recognize that truths about the real world, however distasteful, have to be faced. Moreover, if we are going to admit subjective considerations, there is a fascination in the bleak logic that pervades all of life, including wasps homing in on the nerve ganglia down the length of their prey, cuckoos ejecting their foster brothers (‘Thow mortherer of the heysugge on y braunche’), slave-making ants, and the single-minded – or rather zero-minded – indifference to suffering shown by all parasites and predators. Darwin was bending over backwards to console when he concluded his chapter on the struggle for survival with these words:

  All that we can do, is to keep steadily in mind that each organic being is striving to increase at a geometrical ratio; that each at some period of its life, during some season of the year, during each generation or at intervals, has to struggle for life, and to suffer great destruction. When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt,* that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.

  Shooting the messenger is one of humanity’s sillier foibles, and it underlies a good slice of the opposition to evolution that I mentioned in the Introduction. ‘Teach children that they are animals, and they’ll behave like animals.’ Even if it were true that evolution, or the teaching of evolution, encouraged immorality, that would not imply that the theory of evolution was false. It is quite astonishing how many people cannot grasp this simple point of logic. The fallacy is so common it even has a name, the argumentum ad consequentiam – X is true (or false) because of how much I like (or dislike) its consequences.

  ‘THE MOST EXALTED OBJECT WHICH WE ARE CAPABLE OF CONCEIVING’

  Is ‘the production of the higher animals’ really ‘the most exalted object which we are capable of conceiving’? Most exalted? Really? Are there not more exalted objects? Art? Spirituality? Romeo and Juliet? General Relativity? The Choral Symphony? The Sistine Chapel? Love?

  You have to remember that, for all his personal modesty, Darwin nursed high ambitions. On his world-view, everything about the human mind, all our emotions and spiritual pretensions, all arts and mathematics, philosophy and music, all feats of intellect and of spirit, are themselves productions of the same process that delivered the higher animals. It is not just that without evolved brains spirituality and music would be impossible. More pointedly, brains were naturally selected to increase in capacity and power for utilitarian reasons, until those higher faculties of intellect and spirit emerged as a by-product, and blossomed in the cultural environment provided by group living and language. The Darwinian world-view does not denigrate the higher human faculties, does not ‘reduce’ them to a plane of indignity. It doesn’t even claim to explain them at the sort of level that will seem particularly satisfying, in the way that, say, the Darwinian explanation of a snake-mimicking caterpillar is satisfying. It does, however, claim to have wiped out the impenetrable – not even worth trying to penetrate – mystery that must have dogged all pre-Darwinian efforts to understand life.

  But Darwin doesn’t need any defence from me, and I’ll pass over the question of whether the production of the higher animals is the most exalted object we can conceive, or merely a very exalted object. What, however, of the predicate? Does the production of the higher animals ‘directly follow’ from the war of nature, from famine and death? Well, yes, it does. It directly follows if you understand Darwin’s reasoning, but nobody understood it until the nineteenth century. And many still don’t understand it, or perhaps are reluctant to do so. It is not hard to see why. When you think about it, our own existence, together with its post-Darwinian explicability, is a candidate for the most astonishing fact that any of us are called upon to contemplate, in our whole life, ever. I’ll come to that shortly.

  ‘HAVING BEEN ORIGINALLY BREATHED’

  I have lost count of the irate let
ters I have received from readers of a previous book, taking me to task for, as the writers think, deliberately omitting the vital phrase, ‘by the Creator’ after ‘breathed’? Am I not wantonly distorting Darwin’s intention? These zealous correspondents forget that Darwin’s great book went through six editions. In the first edition, the sentence is as I have written it here. Presumably bowing to pressure from the religious lobby, Darwin inserted ‘by the Creator’ in the second and all subsequent editions. Unless there is a very good reason to the contrary, when quoting On the Origin of Species I always quote the first edition. This is partly because my own copy of that historic print run of 1,250 is one of my most precious possessions, given me by my benefactor and friend Charles Simonyi. But it is also because the first edition is the most historically important. It is the one that thumped the Victorian solar plexus and drove out the wind of centuries. Moreover, later editions, especially the sixth, pandered to more than public opinion. In an attempt to respond to various learned but misguided critics of the first edition, Darwin backtracked and even reversed his position on a number of important points that he had actually got right in the first place. So, ‘having been originally breathed’ it is, with no mention of any Creator.

  It seems that Darwin regretted this sop to religious opinion. In a letter of 1863 to his friend the botanist Joseph Hooker, he said, ‘But I have long regretted that I truckled to public opinion, and used the Pentateuchal term of creation, by which I really meant “appeared” by some wholly unknown process.’ The ‘Pentateuchal term’ Darwin is referring to here is the word ‘creation’. The context, as Francis Darwin explains in his 1887 edition of his father’s letters, was that Darwin was writing to thank Hooker for the loan of a review of a book by Carpenter, in which the anonymous reviewer had spoken of ‘a creative force . . . which Darwin could only express in Pentateuchal terms as the primordial form “into which life was originally breathed”’. Nowadays, we should dispense even with the ‘originally breathed’. What is it that is supposed to have been breathed into what? Presumably the intended reference was to some kind of breath of life,*