Might Intelligent Design turn out to be right?

I am going to argue that for all anybody knows, evolutionary science might develop in such a way that an Intelligent Design (ID) argument would be plausible. Hence, while one might well be justified in saying that ID arguments right now do not work, one is not justified in saying that future ID arguments won't work given a fully developed evolutionary science. Moreover, our current state of biological knowledge, interpreted in an uncontroversial and friendly way, gives us relatively little, if any, reason to accept the claim that ID arguments won't work given a fully developed evolutionary science. (In the interests of full disclosure I should say that I do not think any extant ID argument succeeds in establishing the existence of a designer.)

I shall understand a successful ID argument for a design hypothesis H (say, that God has designed the world) to be an argument that starts with some biological fact F about the world going over and beyond the mere existence of life, a fact such as that the world contains intelligent life, or that the world contains the mammalian eye, or that the world contains highly complex organisms, and then argues:

1. F is very unlikely to happen if the only processes in play are those of evolutionary biology.
2. F is not unlikely to happen on the relevant design hypothesis H.
3. Therefore, F provides significant evidence for the design hypothesis over and against the hypothesis that the only processes in play are those of evolutionary biology.

Assuming that before we give the argument our probability for our design hypothesis (say, that God exists and has created the world) is not too low, we're going to get a successful ID argument as soon as we can find a biological fact F satisfying (1) and (2). My claim, now, is that the present state of evolutionary science gives us little reason to believe that we will not find such a fact F. Note that the above is not the only way of formulating an ID argument. But if we are not in a position to know that no ID argument of this sort is successful, then we are likewise not in a position to know that no ID argument of some sort or otheris successful.

Let's start by considering the fact that evolutionary science gives a statistical explanation of events. It is not shown that, given an earlier state of affairs, bipeds had to evolve. All that is done in an evolutionary explanation is that an evolutionary pathway is traced out and it is argued that that pathway had a certain probability.

Next observe the fact that for most high-level biological states of affairs, we have very little in the way of estimates of estimates of the objective probability of the states of affairs arising. It would be a very, very difficult task, for instance, to estimate the probability that winged vertebrates would exist on earth given the state of things a billion years ago. Thus, although evolutionary explanations are in a significant respect statistical in nature, the statistics have by and large not been worked out.

Now, even if evolutionary science is the whole truth about biology after the initial beginning of life, there will surely be biological features of the world whose objective probability given the initial conditions is tiny. Gould talks of how if we turned the clock back and re-ran the evolutionary processes, we would get something completely different from what we have. That may or may not be true, but surely there are some biological features the probability of whose arising was tiny. For instance, consider the precise kind of pattern that a copperhead snake has on its skin. It may well be that there are myriads of patterns that would do the same job as this pattern does. It may well be that the probability that a snake-like animal would arise with that precise pattern, given the initial state of things, is tiny. (Presumably, if we conjoin enough features, we easily get cases where the probability is about as small as we like.)

Now I have two arguments for my conclusion.

Argument 1: Take a particular feature, intelligence, intelligence of the sort humans have. I think it is far beyond the current state of the art in biology to give estimates of the probability that intelligence would arise given how things were a billion years ago. Intelligence was a solution to certain evolutionary problems, but had things gone somewhat differently, these problems might not have arisen and, for all we know, many, many other solutions are possible. Moreover, we have very little in the way of estimates of the sort of organismic complexity that is needed for intelligence. All in all, we have little reason to assert that intelligence is not very unlikely given how things were a billion years ago. We just don't know how to estimate such a probability, and, unless evolutionary computing ends up yielding experimental data that shows that the evolution of intelligence is easy, it may be quite a while before we know how to estimate such a probability.

A developed evolutionary science will, presumably, assign some probability to the arising of intelligence. But I have argued we have little reason to think that this probability is not going to be very low. Suppose that this probability will in fact be very low, and developed evolutionary science discovers this. Then, a design argument, where the fact in question is the existence of intelligent life (or intelligent life on earth?), will be a good one. For we will have (1). That, by itself, is not enough. Even if it is very unlikely that the precise pattern on a copperhead should arise through evolutionary processes, there being too many other patterns that could do the job, there is no good ID argument based on this pattern, because we do not have reason to believe that a designer would not be unlikely make precisely that pattern.

However, in the case where the fact F is intelligence, and if our design hypothesis is that the world is created by the God of traditional monotheism, then the fact F is not unlikely given the existence of God, since the God of traditional monotheism is perfectly good and generous, and hence it is not unlikely that he would want to create intelligent beings (on earth? that might be an issue to consider) to bestow his goodness on. Hence, we have (2).

Thus, if we do not have much reason to deny that (1) holds of intelligence--and the present state is such that we do not--we neither have much reason to deny that a design argument based on the existence of intelligence will work. Instead, we should just suspend judgment on this. Hence, for all we know, at least one ID argument will be successful.

Argument 2: There is a myriad of biological facts, such as the precise pattern on a copperhead, each of which satisfies (1). This is no evidence at all against evolutionary biology, but just a fact about probabilistic processes like those of mutation, recombination, selection, etc. A priori improbable things happen all the time. Bob wins a lottery. A dart lands within 0.000000000001 mm of point x (this is extremely improbable whatever the point x is, but of course the dart has to land somewhere, so whenever a dart is thrown, it lands within 0.000000000001 mm of some point, and hence always something improbable happens). No surprises there. Let S be the set of very unlikely biological facts like that.

Now to have reason to hold that no ID argument for some relevant design hypothesis will be successful, one would have to have to reason to judge that none of the facts in S satisfies (2). First note that this judgment would go beyond the competence of biological science. Biological science does not estimate the probability that God, if he existed, would design a snake with such-and-such a pattern on its back. So biological science by itself would not be sufficient to establish the unavailability of an ID argument.

Now in the case of the pattern on the back of the snake, we have little reason at present to think that God would design that pattern rather than any of the many others that the snake could have had. Now in the unlikely case that we might discover that the pattern encodes some text in some natural way, the relative probability of that pattern over the others might rise. But we don't expect that to happen.

Nonetheless, I do not think we have much reason to believe that none of the facts in S satisfies (2), and we even do not have much reason to believe that none of the facts in S will be discovered to satisfy (2). So, once again, we have little reason, if any, to believe that a working ID argument won't be discovered in the future.

Conclusions: Being sure that ID will be unsuccessful is unjustified. But there is a proviso that I have to add, which was implicit in my assumption that (1) and (2) are all one needs for ID's success: unless there is good independent reason to deny the conclusion of the ID arguments (this was the assumption that the probability for H before the ID argument isn't too low).