Reality Conditions

Thursday, June 21, 2007

Away again

Tomorrow I wil be heading off to Loops 07, in Morelia, Mexico. I will write my usual conference report afterwards, but that will not be until mid-July. I'll be some time on holiday in Buenos Aires after the conference, and holiday includes holiday from writing work-related posts. There will be other bloggers present at Morelia (Bee, Yidun, and perhaps others I am not aware of) so maybe you'll get multiple perspectives on the meeting.


Monday, June 11, 2007

An examination of Dawkins’ “Ultimate 747” argument

Richard Dawkins’ master argument against the existence of God is spelled out in the fourth chapter of The God Delusion, which is confidently titled “Why there almost certainly is no God”. It may be summarised as follows:

1- God is supposed to be an ultimate explanation for everything there is in the universe, and especially (according to design arguments) for its organized complexity and its friendliness to life.

2- But any God that was responsible for consciously designing the Universe must have a huge degree of complexity itself –at least equal to that of the whole universe.

3- Things with large degrees of complexity are statistically unlikely and stand in need of explanation.

4- So God is an inadequate “ultimate explanation” for the universe –the only possible explanations of complexity are those which, like natural selection or anthropic selection, build up complexity from simple underlying natural laws. (Cranes, not skyhooks, in Dennett’s motto.)

It is obvious that the whole argument rests upon the notion of “complexity”. Just exactly what sense of this concept does Dawkins have in mind, for which very complex things need explaining?

Can it be mathematical complexity as defined in information theory (Shannon information)? But in this sense, a set of particles organized as a living organism would have less complexity than the same particles in a random, uncorrelated state, because you would need more information to specify the latter state than the former. This does not seem right. Can it be the inverse of Shannon information, then –a measure by which random, uncorrelated states have low complexity and highly correlated, low-entropy states have high complexity? But then Dawkins argument fails completely, because physics tells us that the initial state of the universe had very low entropy, and entropy has been growing since. While Dawkins would like to say that in the history of the universe complexity is built from simplicity via the mechanisms of natural selection.

I think there is no rigorously definable sense of “complexity” that has the properties Dawkins requires of it. Ironically, it seems close to the “specified complexity” of Dembski and other creationists! A concept which, as Mark Chu-Carroll’s and others’ criticisms have made clear, has no more technical definition than “something that looks designed”; or, in Behe’s more pedantic but no more precise phrase, “purposeful arrangement of parts”. We can accept the notion, however, as something we understand intuitively and recognize in living beings but cannot at the moment define rigorously, and go on examining the argument. (Accepting this concept as meaningful does not entail accepting Dembski’s creationist arguments, which pretend to prove pseudo-mathematically that complex things in this sense cannot arise by natural selection; because they can.)

Next, let us examine whether this concept of complexity applies to God. Many theists dig their heels here, asserting that the God they believe in is simple. I don’t think this is the best strategy for them. Whether or not there is some metaphysical sense in which their concept of God is simple, I think it is clear it is not the one that Dawkins has in mind. If God is all-knowing, then he must contain at least as much information as the universe, and not only information in the mathematical sense that applies also to random sequences, but information that contains organization, purposeful patterns, and all the marks of “complexity” in the sense we are interested in. A human mind is hugely “complex” in this sense, and God’s mind must be incommensurably more complex.

No, the key premise that must be examined critically is the third one. First, let us clear off that confusing talk of “statistical unlikeliness”. Something “complex” is also “statistically unlikely” only if it appears as result of a stochastic process whose underlying laws do not single out that particular result among many others. For example, the proverbial tornado blowing through a junkyard and assembling a Boeing 747 would be miraculous, because the “complex” outcome results from a process that could also produce billions of other outcomes which are not complex, and we know that the laws governing the behaviour of tornados do not discriminate among those outcomes singling out the complex result as more likely. Just as throwing a coin a thousand times and obtaining always heads is surprising only if we thought that neither the coin nor the way of throwing it were biased. But in the case of God we do not have this knowledge of an underlying process with laws blind to the results; in fact, it would be absurd to postulate such a process, because God is supposed to be an ultimate explanation.

This is really a key point. Dawkins says, in effect: “Look at the typical ID examples of “complexity”; be it the eye of an organism, or the fine-tunedness of laws of nature. They are very statistically unlikely, and so they need an explanation. Design is useless as an explanation because the designer would itself be in need of explanation for the same reason. So “cranes” that build them up from simple things, such as natural selection, are the only possible answer.” But the sentence I have bolded is by no means obvious in absence of context and underlying laws that make the complex thing really “statistically unlikely”. It is certainly not an a priori truth. Think of an Aristotelian view of nature, for example: imagine that species are fixed, each has a “form” or essence which all individuals of the species embody better or worse, and the organisms come to exist and develop by teleological laws, striving to fulfil their potentiality as befits their essence. This is a consistent way the world could have turned out to be, and in it “complex” things do not need any special explanation: the basic laws and principles of the universe make reference to them.

Of course, the real world turned out not to be like this. In the real world the basic laws as far as we know them do not make reference to complex beings, but are completely “blind” to them. Or at least, the whole tendency of the past four centuries leads towards such a conclusion. It is only in the context of this worldview where the apparent design of living organisms raises a problem. Aristotle (to my knowledge) did not use design arguments for the existence of God. Even in the eighteenth century, Hume in his Dialogues still feels free to counter the Design argument by pointing to causes acting in nature such as “generation” and “vegetation”, that are different from design but can produce complexity. But once the post-Newtonian view of the basic laws of the universe as purely “mechanical” (devoid of all teleology) became dominant, how living organisms can come to exist became a pressing problem: for they are really “statistically unlikely” given blind, mechanical underlying laws. Both Paley and Darwin tried to address this problem –only the latter doing it successfully, in a way fully consistent with mechanism and borne out by the evidence.

What Dawkins is doing is to take this story and elevate it to the cosmological or even the metaphysical level. The problem I have with him is not so much taking this step; it is more not acknowledging that it is a step, that it needs to be justified, and that it may reduce the certainty of the conclusion. Taking as a given that complexity is statistically unlikely and needs explanation, Dawkins thinks that God as ultimate explanation is extremely unlikely; I think the “almost certainly” qualifier in the title of the chapter refers really to the infinitesimal probability that something as complex as God may exist “by chance”; hence the “Ultimate 747” moniker. But as I argued, to discuss statistical unlikeliness in absence of underlying laws is vacuous. So Dawkins should have instead argued: “In our experience, and according to the scientific knowledge we have gained in the last centuries, complex things are explained by cranes that build them up from simple tings and laws of nature that are ultimately blind to the complex things. In our experience, complex things stand in need of explanation. So to postulate a very complex thing (such as God) as ultimate, unexplained explanation to the universe is unlikely to be true.”

I think this is a reasonably strong argument, one that may justify someone in calling himself an atheist instead of an agnostic. I am willing to endorse it myself. But it is much less powerful that Dawkins thinks his argument is. The “unlikely” in the conclusion is purely epistemic, not statistical as Dawkins’. The argument makes an inductive leap extrapolating from the current picture we have of how the universe works to say that it is unlikely that its trend will reverse at the cosmological or metaphysical level. If the appearance of teleology is reducible to mechanism or explainable from it in the biological world, then it is most unlikely than teleology (in the form of the intentions of a God) can be an ultimate explanation at a metaphysical level.

This argument assumes, of course, that all instances of teleology are reducible, including its more sophisticated offshoots at a human level, such as consciousness, intentionality and morality. In other words, the argument assumes the naturalistic program in philosophy and stands or falls with it. It must be admitted that this program has not been fully completed yet, but I see the whole course that science has taken since Darwin (if not since Galileo) as pointing towards the plausible truth of naturalism. As long as we don’t have a complete naturalistic account of these higher and more complex forms of teleology, however, I will see theism as a “reasonable” stance someone can take: mind, meaning and morality are pervading in such a way in all our human life, and they come so naturally and irresistibly to our prescientific imaginations as “basic” things, things that can explain things but require no explanation, that it is perfectly understandable that most people think they must be part of the ultimate cause of the universe, instead of late newcomers ultimately built upon blind mechanism, as I am confident they are.

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Saturday, June 02, 2007

Inquiring minds want to know

Google Analytics is way more powerful that Sitemeter. With its help I have uncovered some interesting questions that some people have typed into Google reaching this blog as a consequence. In loose order of increasing weirdness:

are any two things completely identical

world religions influenced the way you think about religion?

if you wake up at a different time and a different place would you be another person

human beings cannot survive without communications, discussi

how does a panda use it's body parts to survive it's life

how was carl gauss teased

what would happen if there was no gravity in school

why my imagination doesn't affect reality

I really like the last one. It brings to mind Philip Dick's dictum "Reality is that which, when you stop believing in it, doesn't go away". In which case, the answer to the question is: "By definition!

Also, it is really strange that my blog is the top Google hit for the panda question, given that I have never blogged about pandas.