Текст книги "The god delusion"

Автор книги: Richard Dawkins

LITTLE GREEN MEN

Suppose Bertrand Russell's parable had concerned not a teapot in outer space but life in outer space – the subject of Sagan's memorable refusal to think with his gut. Once again we cannot disprove it, and the only strictly rational stance is agnosticism. But the hypothesis is no longer frivolous. We don't immediately scent extreme improbability. We can have an interesting argument based on incomplete evidence, and we can write down the kind of evidence that would decrease our uncertainty. We'd be outraged if our government invested in expensive telescopes for the sole purpose of searching for orbiting teapots. But we can appreciate the case for spending money on SETI, the Search for Extraterrestrial Intelligence, using radio telescopes to scan the skies in the hope of picking up signals from intelligent aliens.

I praised Carl Sagan for disavowing gut feelings about alien life. But one can (and Sagan did) make a sober assessment of what we would need to know in order to estimate the probability. This might start from nothing more than a listing of our points of ignorance, as in the famous Drake Equation which, in Paul Davies's phrase, collects probabilities. It states that to estimate the number of independently evolved civilizations in the universe you must multiply seven terms together. The seven include the number of stars, the number of Earth-like planets per star, and the probability of this, that and the other which I need not list because the only point I am making is that they are all unknown, or estimated with enormous margins of error. When so many terms that are either completely or almost completely unknown are multiplied up, the product – the estimated number of alien civilizations – has such colossal error bars that agnosticism seems a very reasonable, if not the only credible stance.

Some of the terms in the Drake Equation are already less unknown than when he first wrote it down in 1961. At that time, our solar system of planets orbiting a central star was the only one known, together with the local analogies provided by Jupiter's and Saturn's satellite systems. Our best estimate of the number of orbiting systems in the universe was based on theoretical models, coupled with the more informal 'principle of mediocrity': the feeling (born of uncomfortable history lessons from Copernicus, Hubble and others) that there should be nothing particularly unusual about the place where we happen to live. Unfortunately, the principle of mediocrity is in its turn emasculated by the 'anthropic' principle (see Chapter 4): if our solar system really were the only one in the universe, this is precisely where we, as beings who think about such matters, would have to be living. The very fact of our existence could retrospectively determine that we live in an extremely unmediocre place.

But today's estimates of the ubiquity of solar systems are no longer based on the principle of mediocrity; they are informed by direct evidence. The spectroscope, nemesis of Comte's positivism, strikes again. Our telescopes are scarcely powerful enough to see planets around other stars directly. But the position of a star is perturbed by the gravitational pull of its planets as they whirl around it, and spectroscopes can pick up the Doppler shifts in the star's spectrum, at least in cases where the perturbing planet is large. Mostly using this method, at the time of writing we now know of 170 extra-solar planets orbiting 147 stars,⁴⁴ but the figure will certainly have increased by the time you read this book. So far, they are bulky 'Jupiters', because only Jupiters are large enough to perturb their stars into the zone of detectability of present-day spectroscopes.

We have at least quantitatively improved our estimate of one previously shrouded term of the Drake Equation. This permits a significant, if still moderate, easing of our agnosticism about the final value yielded by the equation. We must still be agnostic about life on other worlds – but a little bit less agnostic, because we are just that bit less ignorant. Science can chip away at agnosticism, in a way that Huxley bent over backwards to deny for the special case of God. I am arguing that, notwithstanding the polite abstinence of Huxley, Gould and many others, the God question is not in principle and forever outside the remit of science. As with the nature of the stars, contra Comte, and as with the likelihood of life in orbit around them, science can make at least probabilistic inroads into the territory of agnosticism.

My definition of the God Hypothesis included the words 'superhuman' and 'supernatural'. To clarify the difference, imagine that a SETI radio telescope actually did pick up a signal from outer space which showed, unequivocally, that we are not alone. It is a non-trivial question, by the way, what kind of signal would convince us of its intelligent origin. A good approach is to turn the question around. What should we intelligently do in order to advertise our presence to extraterrestrial listeners? Rhythmic pulses wouldn't do it. Jocelyn Bell Burnell, the radio astronomer who first discovered the pulsar in 1967, was moved by the precision of its 1.33-second periodicity to name it, tongue in cheek, the LGM (Little Green Men) signal. She later found a second pulsar, elsewhere in the sky and of different periodicity, which pretty much disposed of the LGM hypothesis. Metronomic rhythms can be generated by many non-intelligent phenomena, from swaying branches to dripping water, from time lags in self-regulating feedback loops to spinning and orbiting celestial bodies. More than a thousand pulsars have now been found in our galaxy, and it is generally accepted that each one is a spinning neutron star emitting radio energy that sweeps around like a lighthouse beam. It is amazing to think of a star rotating on a timescale of seconds (imagine if each of our days lasted 1.33 seconds instead of 24 hours), but just about everything we know of neutron stars is amazing. The point is that the pulsar phenomenon is now understood as a product of simple physics, not intelligence.

Nothing simply rhythmic, then, would announce our intelligent presence to the waiting universe. Prime numbers are often mentioned as the recipe of choice, since it is difficult to think of a purely physical process that could generate them. Whether by detecting prime numbers or by some other means, imagine that SETI does come up with unequivocal evidence of extraterrestrial intelligence, followed, perhaps, by a massive transmission of knowledge and wisdom, along the science-fiction lines of Fred Hoyle's A for Andromeda or Carl Sagan's Contact. How should we respond? A pardonable reaction would be something akin to worship, for any civilization capable of broadcasting a signal over such an immense distance is likely to be greatly superior to ours. Even if that civilization is not more advanced than ours at the time of transmission, the enormous distance between us entitles us to calculate that they must be millennia ahead of us by the time the message reaches us (unless they have driven themselves extinct, which is not unlikely).

Whether we ever get to know about them or not, there are very probably alien civilizations that are superhuman, to the point of being god-like in ways that exceed anything a theologian could possibly imagine. Their technical achievements would seem as supernatural to us as ours would seem to a Dark Age peasant transported to the twenty-first century. Imagine his response to a laptop computer, a mobile telephone, a hydrogen bomb or a jumbo jet. As Arthur C. Clarke put it, in his Third Law: 'Any sufficiently advanced technology is indistinguishable from magic.' The miracles wrought by our technology would have seemed to the ancients no less remarkable than the tales of Moses parting the waters, or Jesus walking upon them. The aliens of our SETI signal would be to us like gods, just as missionaries were treated as gods (and exploited the undeserved honour to the hilt) when they turned up in Stone Age cultures bearing guns, telescopes, matches, and almanacs predicting eclipses to the second.

In what sense, then, would the most advanced SETI aliens not be gods? In what sense would they be superhuman but not supernatural? In a very important sense, which goes to the heart of this book. The crucial difference between gods and god-like extraterrestrials lies not in their properties but in their provenance. Entities that are complex enough to be intelligent are products of an evolutionary process. No matter how god-like they may seem when we encounter them, they didn't start that way. Science-fiction authors, such as Daniel F. Galouye in Counterfeit World, have even suggested (and I cannot think how to disprove it) that we live in a computer simulation, set up by some vastly superior civilization. But the simulators themselves would have to come from somewhere. The laws of probability forbid all notions of their spontaneously appearing without simpler antecedents. They probably owe their existence to a (perhaps unfamiliar) version of Darwinian evolution: some sort of cumulatively ratcheting 'crane' as opposed to 'skyhook', to use Daniel Dennett's terminology.⁴⁵ Skyhooks – including all gods – are magic spells. They do no bona fide explanatory work and demand more explanation than they provide. Cranes are explanatory devices that actually do explain. Natural selection is the champion crane of all time. It has lifted life from primeval simplicity to the dizzy heights of complexity, beauty and apparent design that dazzle us today. This will be a dominant theme of Chapter 4, 'Why there almost certainly is no God'. But first, before proceeding with my main reason for actively disbelieving in God's existence, I have a responsibility to dispose of the positive arguments for belief that have been offered through history.

CHAPTER 3. Arguments for God's existence

A professorship of theology should have no place in our institution.

THOMAS JEFFERSON

Arguments for the existence of God have been codified for centuries by theologians, and supplemented by others, including purveyors of misconceived 'common sense'.

THOMAS AQUINAS' 'PROOFS'

The five 'proofs' asserted by Thomas Aquinas in the thirteenth century don't prove anything, and are easily – though I hesitate to say so, given his eminence – exposed as vacuous. The first three are just different ways of saying the same thing, and they can be considered together. All involve an infinite regress – the answer to a question raises a prior question, and so on ad infinitum.

1 The Unmoved Mover. Nothing moves without a prior mover. This leads us to a regress, from which the only escape is God. Something had to make the first move, and that something we call God.

2 The Uncaused Cause. Nothing is caused by itself. Every effect has a prior cause, and again we are pushed back into regress. This has to be terminated by a first cause, which we call God.

3 The Cosmological Argument. There must have been a time when no physical things existed. But, since physical things exist now, there must have been something non-physical to bring them into existence, and that something we call God.

All three of these arguments rely upon the idea of a regress and invoke God to terminate it. They make the entirely unwarranted assumption that God himself is immune to the regress. Even if we allow the dubious luxury of arbitrarily conjuring up a terminator to an infinite regress and giving it a name, simply because we need one, there is absolutely no reason to endow that terminator with any of the properties normally ascribed to God: omnipotence, omniscience, goodness, creativity of design, to say nothing of such human attributes as listening to prayers, forgiving sins and reading innermost thoughts. Incidentally, it has not escaped the notice of logicians that omniscience and omnipotence are mutually incompatible. If God is omniscient, he must already know how he is going to intervene to change the course of history using his omnipotence. But that means he can't change his mind about his intervention, which means he is not omnipotent. Karen Owens has captured this witty little paradox in equally engaging verse:

 
Can omniscient God, who
Knows the future, find
The omnipotence to
Change His future mind?
 

To return to the infinite regress and the futility of invoking God to terminate it, it is more parsimonious to conjure up, say, a 'big bang singularity', or some other physical concept as yet unknown. Calling it God is at best unhelpful and at worst perniciously misleading. Edward Lear's Nonsense Recipe for Crumboblious Cutlets invites us to 'Procure some strips of beef, and having cut them into the smallest possible pieces, proceed to cut them still smaller, eight or perhaps nine times.' Some regresses do reach a natural terminator. Scientists used to wonder what would happen if you could dissect, say, gold into the smallest possible pieces. Why shouldn't you cut one of those pieces in half and produce an even smaller smidgen of gold? The regress in this case is decisively terminated by the atom. The smallest possible piece of gold is a nucleus consisting of exactly seventy-nine protons and a slightly larger number of neutrons, attended by a swarm of seventy-nine electrons. If you 'cut' gold any further than the level of the single atom, whatever else you get it is not gold. The atom provides a natural terminator to the Crumboblious Cutlets type of regress. It is by no means clear that God provides a natural terminator to the regresses of Aquinas. That's putting it mildly, as we shall see later. Let's move on down Aquinas' list.

4 The Argument from Degree. We notice that things in the world differ. There are degrees of, say, goodness or perfection. But we judge these degrees only by comparison with a maximum. Humans can be both good and bad, so the maximum goodness cannot rest in us. Therefore there must be some other maximum to set the standard for perfection, and we call that maximum God.

That's an argument? You might as well say, people vary in smelliness but we can make the comparison only by reference to a perfect maximum of conceivable smelliness. Therefore there must exist a pre-eminently peerless stinker, and we call him God. Or substitute any dimension of comparison you like, and derive an equivalently fatuous conclusion.

5 The Teleological Argument, or Argument from Design. Things in the world, especially living things, look as though they have been designed. Nothing that we know looks designed unless it is designed. Therefore there must have been a designer, and we call him God.*)  10.
  I cannot help being reminded of the immortal syllogism that was smuggled into a Euclidean proof by a schoolfriend, when we were studying geometry together: 'Triangle ABC looks isosceles. Therefore...'


[Закрыть] Aquinas himself used the analogy of an arrow moving towards a target, but a modern heat-seeking anti-aircraft missile would have suited his purpose better.

The argument from design is the only one still in regular use today, and it still sounds to many like the ultimate knockdown argument. The young Darwin was impressed by it when, as a Cambridge undergraduate, he read it in William Paley's Natural Theology. Unfortunately for Paley, the mature Darwin blew it out of the water. There has probably never been a more devastating rout of popular belief by clever reasoning than Charles Darwin's destruction of the argument from design. It was so unexpected. Thanks to Darwin, it is no longer true to say that nothing that we know looks designed unless it is designed. Evolution by natural selection produces an excellent simulacrum of design, mounting prodigious heights of complexity and elegance. And among these eminences of pseudo-design are nervous systems which – among their more modest accomplishments – manifest goal-seeking behaviour that, even in a tiny insect, resembles a sophisticated heat-seeking missile more than a simple arrow on target. I shall return to the argument from design in Chapter 4.

THE ONTOLOGICAL ARGUMENT AND OTHER A PRIORI ARGUMENTS

Arguments for God's existence fall into two main categories, the a priori and the a posteriori. Thomas Aquinas' five are a posteriori arguments, relying upon inspection of the world. The most famous of the a priori arguments, those that rely upon pure armchair ratiocination, is the ontological argument, proposed by St Anselm of Canterbury in 1078 and restated in different forms by numerous philosophers ever since. An odd aspect of Anselm's argument is that it was originally addressed not to humans but to God himself, in the form of a prayer (you'd think that any entity capable of listening to a prayer would need no convincing of his own existence).

It is possible to conceive, Anselm said, of a being than which nothing greater can be conceived. Even an atheist can conceive of such a superlative being, though he would deny its existence in the real world. But, goes the argument, a being that doesn't exist in the real world is, by that very fact, less than perfect. Therefore we have a contradiction and, hey presto, God exists!

Let me translate this infantile argument into the appropriate language, which is the language of the playground:

 
'Bet you I can prove God exists.'
'Bet you can't.'
'Right then, imagine the most perfect perfect perfect thing possible.'
'Okay, now what?'
'Now, is that perfect perfect perfect thing real? Does it exist?'
'No, it's only in my mind.'
'But if it was real it would be even more perfect, because a really really perfect thing would have to be better than a silly old imaginary thing. So I've proved that God exists. Nur Nurny Nur Nur. All atheists are fools.'
 

I had my childish wiseacre choose the word 'fools' advisedly. Anselm himself quoted the first verse of Psalm 14, 'The fool hath said in his heart, There is no God,' and he had the cheek to use the name 'fool' (Latin insipiens) for his hypothetical atheist:

Hence, even the fool is convinced that something exists in the understanding, at least, than which nothing greater can be conceived. For, when he hears of this, he understands it. And whatever is understood, exists in the understanding. And assuredly that, than which nothing greater can be conceived, cannot exist in the understanding alone. For, suppose it exists in the understanding alone: then it can be conceived to exist in reality; which is greater.

The very idea that grand conclusions could follow from such logo-machist trickery offends me aesthetically, so I must take care to refrain from bandying words like 'fool'. Bertrand Russell (no fool) interestingly said, 'It is easier to feel convinced that [the ontological argument] must be fallacious than it is to find out precisely where the fallacy lies.' Russell himself, as a young man, was briefly convinced by it:

I remember the precise moment, one day in 1894, as I was walking along Trinity Lane, when I saw in a flash (or thought I saw) that the ontological argument is valid. I had gone out to buy a tin of tobacco; on my way back, I suddenly threw it up in the air, and exclaimed as I caught it: 'Great Scott, the ontological argument is sound.'

Why, I wonder, didn't he say something like: 'Great Scott, the ontological argument seems to be plausible. But isn't it too good to be true that a grand truth about the cosmos should follow from a mere word game? I'd better set to work to resolve what is perhaps a paradox like those of Zeno.' The Greeks had a hard time seeing through Zeno's 'proof that Achilles would never catch the tortoise.*)  11.
  Zeno's paradox is too well known for the details to be promoted out of a footnote. Achilles can run ten times as fast as the tortoise, so he gives the animal, say, 100 yards' start. Achilles runs 100 yards, and the tortoise is now 10 yards ahead. Achilles runs the 10 yards and the tortoise is now 1 yard ahead. Achilles runs the 1 yard, and the tortoise is still a tenth of a yard ahead. and so on ad infinitum, so Achilles never catches the tortoise.


[Закрыть] But they had the sense not to conclude that therefore Achilles really would fail to catch the tortoise. Instead, they called it a paradox and waited for later generations of mathematicians to explain it (with, as it turned out, the theory of infinite series converging on a limiting value). Russell himself, of course, was as well qualified as anyone to understand why no tobacco tins should be thrown up in celebration of Achilles' failure to catch the tortoise. Why didn't he exercise the same caution over St Anselm? I suspect that he was an exaggeratedly fair-minded atheist, over-eager to be disillusioned if logic seemed to require it.*)  12.
  We might be seeing something similar today in the over-publicized tergiversation of the philosopher Antony Flew, who announced in his old age that he had been converted to belief in some sort of deity (triggering a frenzy of eager repetition all around the Internet). On the other hand, Russell was a great philosopher. Russell won the Nobel Prize. Maybe Flew's alleged conversion will be rewarded with the Templeton Prize. A first step in that direction is his ignominious decision to accept, in 2006, the 'Phillip E. Johnson Award for Liberty and Truth'. The first holder of the Phillip E. Johnson Award was Phillip E. Johnson, the lawyer credited with founding the Intelligent Design 'wedge strategy'. Flew will be the second holder. The awarding university is BIOLA, the Bible Institute of Los Angeles. One can't help wondering whether Flew realizes that he is being used. See Victor Stenger, 'Flew's flawed science', Free Inquiry 25: 2, 2005, 17–18; www.secularhumanism.org/index.php?section=library&page=stenger_25_2.


[Закрыть] Or perhaps the answer lies in something Russell himself wrote in 1946, long after he had rumbled the ontological argument:

The real question is: Is there anything we can think of which, by the mere fact that we can think of it, is shown to exist outside our thought? Every philosopher would like to say yes, because a philosopher's job is to find out things about the world by thinking rather than observing. If yes is the right answer, there is a bridge from pure thought to things. If not, not.

My own feeling, to the contrary, would have been an automatic, deep suspicion of any line of reasoning that reached such a significant conclusion without feeding in a single piece of data from the real world. Perhaps that indicates no more than that I am a scientist rather than a philosopher. Philosophers down the centuries have indeed taken the ontological argument seriously, both for and against. The atheist philosopher J. L. Mackie gives a particularly clear discussion in The Miracle of Theism. I mean it as a compliment when I say that you could almost define a philosopher as someone who won't take common sense for an answer.

The most definitive refutations of the ontological argument are usually attributed to the philosophers David Hume (1711-76) and Immanuel Kant (1724–1804). Kant identified the trick card up Anselm's sleeve as his slippery assumption that 'existence' is more 'perfect' than non-existence. The American philosopher Norman Malcolm put it like this: 'The doctrine that existence is a perfection is remarkably queer. It makes sense and is true to say that my future house will be a better one if it is insulated than if it is not insulated; but what could it mean to say that it will be a better house if it exists than if it does not?'⁴⁶ Another philosopher, the Australian Douglas Gasking, made the point with his ironic 'proof that God does not exist (Anselm's contemporary Gaunilo had suggested a somewhat similar reductio).

 
1 The creation of the world is the most marvellous achievement imaginable.
 

 
2 The merit of an achievement is the product of (a) its intrinsic quality, and (b) the ability of its creator.
 

 
3 The greater the disability (or handicap) of the creator, the more impressive the achievement.
 

 
4 The most formidable handicap for a creator would be nonexistence.
 

 
5 Therefore if we suppose that the universe is the product of an existent creator we can conceive a greater being – namely, one who created everything while not existing.
 

 
6 An existing God therefore would not be a being greater than which a greater cannot be conceived because an even more formidable and incredible creator would be a God which did not exist.
 

Ergo:

 
7 God does not exist.
 

Needless to say, Gasking didn't really prove that God does not exist. By the same token, Anselm didn't prove that he does. The only difference is, Gasking was being funny on purpose. As he realized, the existence or non-existence of God is too big a question to be decided by 'dialectical prestidigitation'. And I don't think the slippery use of existence as an indicator of perfection is the worst of the argument's problems. I've forgotten the details, but I once piqued a gathering of theologians and philosophers by adapting the ontological argument to prove that pigs can fly. They felt the need to resort to Modal Logic to prove that I was wrong.

The ontological argument, like all a priori arguments for the existence of God, reminds me of the old man in Aldous Huxley's Point Counter Point who discovered a mathematical proof of the existence of God:

You know the formula, m over nought equals infinity, m being any positive number? Well, why not reduce the equation to a simpler form by multiplying both sides by nought. In which case you have m equals infinity times nought. That is to say that a positive number is the product of zero and infinity. Doesn't that demonstrate the creation of the universe by an infinite power out of nothing? Doesn't it?

Or there is the notorious eighteenth-century debate on the existence of God, staged by Catherine the Great between Euler, the Swiss mathematician, and Diderot, the great encyclopedist of the Enlightenment. The pious Euler advanced upon the atheistic Diderot and, in tones of the utmost conviction, delivered his challenge: 'Monsieur, (a + bⁿ)/n = x, therefore God exists. Reply!' Diderot was cowed into withdrawal, and one version of the story has him withdrawing all the way back to France.

Euler was employing what might be called the Argument from Blinding with Science (in this case mathematics). David Mills, in Atheist Universe, transcribes a radio interview of himself by a religious spokesman, who invoked the Law of Conservation of Mass-Energy in a weirdly ineffectual attempt to blind with science: 'Since we're all composed of matter and energy, doesn't that scientific principle lend credibility to a belief in eternal life?' Mills replied more patiently and politely than I would have, for what the interviewer was saying, translated into English, was no more than: 'When we die, none of the atoms of our body (and none of the energy) are lost. Therefore we are immortal.'

Even I, with my long experience, have never encountered wishful thinking as silly as that. I have, however, met many of the wonderful 'proofs' collected at http://www.godlessgeeks.com/LINKS/GodProof.htm, a richly comic numbered list of 'Over Three Hundred Proofs of God's Existence'. Here's a hilarious half-dozen, beginning with Proof Number 36.

36 Argument from Incomplete Devastation: A plane crashed killing 143 passengers and crew. But one child survived with only third-degree burns. Therefore God exists.

37 Argument from Possible Worlds: If things had been different, then things would be different. That would be bad. Therefore God exists.

38 Argument from Sheer Will: I do believe in God! I do believe in God! I do I do I do. I do believe in God! Therefore God exists.

39 Argument from Non-belief: The majority of the world's population are non-believers in Christianity. This is just what Satan intended. Therefore God exists.

40 Argument from Post-Death Experience: Person X died an atheist. He now realizes his mistake. Therefore God exists.

41 Argument from Emotional Blackmail: God loves you. How could you be so heartless as not to believe in him? Therefore God exists.