From the Tail: Betting on Uncertainty

I think I know where you stand on the ongoing federal court case in Pennsylvania, where parents have sued to block the teaching of intelligent design in their schools. Your position notwithstanding, only 13% of the respondents to a November 2004 Gallup poll believed that God has no part to play in the evolution or creation of human beings. Fully 45% said they believe that God created humans in their present form less than 10,000 years ago!

What's going on here? Many (perhaps even a majority) of these respondents were taught evolution in school. Did they choose to disregard it merely because it contradicted their religion? They do seem to accept a whole host of other things during the course of their education which may contradict it as well. For example, there appears to be far less skepticism about the assertion that humans occupy a vanishingly small fraction of the universe. I'll throw out three other explanations that are often advanced, but which I believe to be inadequate as well:

1. Natural selection is not a good enough explanation for the facts: Clearly, it is.
2. Natural selection has not been properly explained to the general public: Sure there are common misconceptions, but proponents have had enough school time, air time and book sales mindshare to make their points many times over.
3. Religious zealots have successfully mounted a campaign based on lies, that has distorted the true meaning of natural selection: This has conspiracy theory overtones.  There are too many people who do not believe in natural selection -- have they all been brainwashed?

My explanation is simply this: Human beings have a strong visceral reaction to disbelieve any theory which injects uncertainty or chance into their world view. They will cling to some other "explanation" of the facts which does not depend on chance until provided with absolutely incontrovertible proof to the contrary.

Part of the problem is that we all deal with uncertainty in our daily lives, but it is, at best an uncomfortable co-existence. Think of all the stress we go through because of uncertainty. Or how it destabilizes us and makes us miserable (what fraction of the time are you worrying about things that are certain?). In addition to hating it, we confuse uncertainty with ignorance (which is just a special case), and believe that eliminating uncertainty is merely a matter of knowing more. Given this view, most people have no room for chance in the basic laws of nature. My hunch is that that is what many proponents of Intelligent Design dislike about natural selection. Actually, it's more than a hunch. The Discovery Institute, a think tank whose mission is to make "a positive vision of the future practical", (but which appears to devote a bulk of its resources to promoting intelligent design) has gotten 400 scientists to sign up to the following "Scientific Dissent from Darwinism":   

We are skeptical of the claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged.

In this world of sophisticated polling and sound bites, I think that the folks at the Discovery Institute have gotten their message down pat. To be sure, natural selection is not a theory of mere chance. But without uncertainty it cannot proceed. In other words, Natural Selection is a theory that is not of chance, but one that requires it.  The advocates of Intelligent Design are objecting to the "purposeless" nature of natural selection and replacing it with the will of a creator. It doesn't really help matters for Darwinians to claim that chance plays a marginal role, and that the appeal to chance is a proxy for some other insidious agenda. Chance is the true bone of contention. In fact, as Jacques Monod put it over thirty years ago:

Even today a good many distinguished minds seem unable to accept or even to understand that from a source of noise, natural selection could quite unaided have drawn all music of the biosphere. Indeed, natural selection operates upon the products of chance and knows no other nourishment; but it operates in a domain of very demanding conditions, from which chance is banned. It is not to chance but to these conditions that evolution owes its generally progressive course.

The inability of otherwise reasonable people to accept a fundamental role for randomness is not restricted to religious people -- scientists are hardly immune to it. We know that even Einstein had issues with God and dice in the context of Quantum Mechanics. Earlier, in 1857, when Ludwig Boltzmann explained the Second Law of Thermodynamics by introducing, for the first time, probability in a fundamental law, he was met with extreme skepticism and hostility. He had broken with the classical Newtonian imperative of determinism, and so could not be right. After much heartache over answering his many critics, Boltzmann (who had been struggling with other problems as well) hanged himself while on holiday.

Of course one reason we hate to deal with uncertainty is that we are so ill equipped to do so. Even when the facts are clearly laid out, the cleverest people (probabalists included) make mistakes. I can't resist providing the following example:

William is a short, shy man. He has a passion for poetry and lives strolling through art museums. As a child he was often bullied by his classmates. Do you suppose that Williams is (a) a farmer, (b) a classics scholar?

Everyone I ask this question chooses (b). But that isn't right. There are vastly more farmers than classics scholars, and even if a small fraction of farmers match William's characteristics, that number is likely to be larger than the entire set of classics scholars. (Did you just get burned by your meager probabilistic reasoning faculties?) The psychologists Kahneman and Tversky pioneered the field of behavioral economics, which establishes among other things that our heuristics for reasoning about uncertainty are quite bad. You can probably think of many patently dumb things that people have done with their money and with their lives when a simple evaluation of the uncertainties would have resulted in better outcomes.

So back to getting people to accept uncertainty as an inherent part of the world. As you can probably tell, I am not holding my breath. On evolution, the timescales are too long to be able to provide the incontrovertible proof to change most people's minds. Maybe a better approach is to reason by analogy. There is an absolutely staggering amount of purposeless evolution unfolding at breakneck speed before our very eyes. I am talking about the Web, the very medium through which you are reading this. In only about ten years a significant portion of the world's knowledge has become available, is almost instantaneously accessible, and it's free. Consider these figures from a recent article by Kevin Kelly. The thing we call the Web has

• more than 600 billion web pages available, which are accessible by about 1 billion people.
• 50 million simultaneous auctions going on on Ebay,  adding up to  1.5 billion a year.
• 2 billion searches a month being done on  Google alone.

Think back to what you were doing ten years ago. Did you ever really think that any of this would happen? The scale at which the internet operates was envisioned by none of the engineers and computer scientists who collaboratively attempted to design the basic substrate of protocols upon which it runs. In truth, the innovations and designs of the web come from the collective energies of its users, and not according to an intelligent design or a blueprint. Here the purposeless of evolution is much easier to see. One day in the future some theory will reveal as a simple consequence, why all of a sudden in the years 2004-05, there sprung up 50 million blogs, with a new one coming on line every 2 seconds. This theory of evolution will be framed by a Law and this law will have at its core an indelible, irreducible kernel of chance. And chances are, most people will have a hard time believing it.