Although supremely confident that he has just demolished any rationale for believing in God with his argument based on God's alleged improbability, professor Dawkins loads another round into the chamber just in case theism is still twitching.
Recall that his argument is a reply to the theist's claim that the complexity of the universe, its finely-tuned forces and parameters, are so extraordinarily improbable as to make an intelligent cause the only plausible explanation for them. Dawkins has argued, incorrectly, that this cause would itself have to be even more extraordinarily improbable and therefore not a plausible explanation at all. The theist cannot explain God and therefore has no reason to believe he exists, or so Dawkins implies.
Now he imagines himself to be applying the coup de grace to theism by presenting what he fancies to be a more plausible explanation for the universe's existence. Since we should always believe that which is more plausible instead of that which is less plausible we should accept his explanation he's about to offer rather than the God Hypothesis. His argument combines what has come to be called the Anthropic Principle (actually Dawkins employs what is called the Weak Anthropic Principle, WAP) with the Many-Worlds Hypothesis MWH).
Suppose you purchase a lottery ticket and learn that you are the only person who did so. Nevertheless, on the day of the drawing your five-digit ticket number, as highly improbable as it may be, comes up. You've won. The odds against it are extraordinary, but there's no point in objecting that it's almost impossible that your number could have been randomly drawn since you obviously won and the only way that could have happened is if your number was the one selected.
The universe is something like that. It's admittedly incredible that the forces and structural parameters are what they are, but we shouldn't be too surprised, the argument goes, since if they weren't exactly as they are the universe, if it existed all, would not have been able to produce life, and we wouldn't be here to notice the fact. Thus, the universe has to be the way it is for us to be here at all. That's the WAP and, Dawkins believes, it's all the explanation that's needed or which can be given for how the world happens to be so exquisitely calibrated for life.
This, of course, sounds like sophistry to most people who don't think like atheists. Consider a prisoner placed in a room with a dozen card tables each of which has on it ten complete packs of thoroughly shuffled playing cards. The man is told that from each of the decks on each of the tables he is to draw four cards at random. The first time he draws something other than an ace a poison gas will be released and he will die instantly. The man begins his task, despairing of making it past even the first card. Yet to his astonishment he completes the first table having drawn all aces, then the second, and finally the last. Unable to comprehend his good fortune, he wonders aloud how it could possibly have happened that he drew all aces, purely by chance, and is still alive. He's convinced, quite reasonably, that someone must have tinkered with the cards. A voice comes over the intercom, the voice of Richard Dawkins, say, and intones that he shouldn't conclude that there was any tinkering. Would it not be even more astonishing that an invisible man of some sort had somehow influenced the card selection? No, it was all just coincidence, and the prisoner shouldn't marvel that he drew 120 aces because if it had been otherwise he wouldn't be alive to notice. That's essentially Dawkins' explanation for the way the world is.
Needless to say, many people find this less than persuasive, so Dawkins imports another idea to buttress it. This is the theory that our universe or at least our region of the universe is just one of a near infinite number of such regions (called domains) all having different physical properties. Dawkins seizes upon this idea, the Many Worlds Hypothesis, and argues that given so many possibilities it's highly likely that there's at least one domain which has the particular set of properties necessary to sustain advanced life forms, and it just happens that we're in it. In other words, if enough lottery tickets are sold one of them just has to have the winning number.
The MWH serves as a deus ex machina for Dawkins and by combining it with the argument from God's improbability Dawkins has atheist hearts palpitating the world over. You, however, may be asking yourself several questions:
1. Is a near infinite number of worlds likely to exist? Dawkins replies that no, it's very unlikely, but it's even less likely that God exists so it makes more sense to believe the MWH than to believe in God.
2. You may also wonder where all those universes came from and how they came to have the properties they do. If you do you're wondering about more than Dawkins does. There is no conceivable mechanism for generating these universes, nor for producing the laws which would govern them. How do physical laws get created anyway?
3. You may also be asking whether this has anything to do with science. After all, Dawkins tells us several times in the book that he bases his beliefs on evidence. What's the evidence for other worlds? There is none. The MWH violates the principle that the preferred explanation be one for which we have evidence or which can be inferred from what we already know. We have reason to believe that information and fine-tuning can be produced by minds. We have no evidence, nor can have, of other universes.
We have evidence that minds can create beauty, elegance, harmony, etc. but no evidence that chance can.
Yet Dawkins is prepared to believe, despite the lack of any empirical evidence, there are an infinite number of universes before he'll believe that there's a mind behind it all. It reminds me of something I read about Michael Shermer, another prominent atheist. Shermer once said that even if we were to discover a planet with the words "Yahweh Made Me" inscribed in letters so large as to be visible from a vast distance he'd still believe that it was an amazing accident.
Philosopher Alvin Plantinga observes that Dawkins seems to be arguing that because it is possible that life arose without God, therefore life must have arisen without God. Plantinga writes:
It's worth meditating, if only for a moment, on the striking distance, here, between premise and conclusion. The premise tells us, substantially, that there are no irrefutable objections to its being possible that unguided evolution has produced all of the wonders of the living world; the conclusion is that it is true that unguided evolution has indeed produced all of those wonders. The argument form seems to be something like:
We know of no irrefutable objections to its being possible that p; Therefore, p is true.
Philosophers sometimes propound invalid arguments (I've propounded a few myself); few of those arguments display the truly colossal distance between premise and conclusion sported by this one. I come into the departmental office and announce to the chairman that the dean has just authorized a $50,000 raise for me; naturally he wants to know why I think so. I tell him that we know of no irrefutable objections to its being possible that the dean has done that. My guess is he'd gently suggest that it is high time for me to retire.
Dawkins rests his entire case on the arguments of chapter 4, but those arguments come nowhere near demonstrating what he thinks they do. Indeed, they're an exceedingly flimsy platform upon which to rest a conclusion so weighty as that God does not exist. Perhaps aware of the logical mire into which he has stepped, he subtly changes the subject, diverting our attention from his attack on God to his attack on creationism, organized religion, and anything else religious that crosses his field of vision. Whatever may be the merits of these criticisms, they're irrelevant to the question of the existence of God. Indeed, belief in God is left completely unscathed by The God Delusion.
RLC