I’ve gotten involved in a fairly lengthy discussion of Intelligent Design on reddit as a result of posting my review of Darwin’s Doubt there. Most of the discussion has centred around a couple of key points, that my interlocutors seem to insist on repeating, ad nauseum.
The first point is the inherent implausibility of Evolutionary Theory with regards to explaining speciation, and the second is their refusal to accept that Intelligent Design is an implicitly religious argument. These two points are critical problems in their treatment of this argument.
Plausibility is relational. The implausibility of an event is entirely irrelevant when determining if it happened, or not. Plausibility matters if and only if we have several competing theories. Given time/resource constraints (and assuming roughly proportional costs), we should start testing the most plausible explanations first. But we can’t simply say “well, since x is more plausible than y, we’ll just assume that y didn’t happen”. That’s not the way we work when genuinely seeking explanations. That’s the way we work when x fits our biases, and we don’t want to entertain that it could be false.
To do some basic math: a human can produce 8.4 million different gametes just by shuffling chromosomes (not even taking into account crossing over) so with two gametes combining it’d be 8.4mil times 8.4mil = 70.6×10^12 possible combinations of DNA from any pairing of any two humans. The odds of the particular set of DNA that I have popping out of my parents is 70.6×10^12 to 1, against. Let me write that out in full: 70,600,000,000,000 to 1. Against. (this information from Freeman, S, Harrington M., Sharp, J. 2014. BIOLOGICAL SCIENCE, 2nd Canadian Edition, courtesy of a friendly biologist)
Let’s tone it down, as I’m sure that not all possible combinations are viable, and just say that there’s a one in a million chance of any particular set of DNA combining from ones parents. Notice that I’ve knocked off 6 zeros there, meaning I’ve eliminated more than 99.99999% of the possible combinations. If more than 0.00001% of the possible combinations of DNA are viable then I am vastly underestimating these odds, which will empower my conclusion.
Now each parent also had a one in a million chance of having the DNA that they do. So the odds of Mum’s DNA (set A) combining with Dad’s DNA (set B), to produce my DNA (set C) would be a million times a million times a million. Go up another generation, and we have 4 more sets to introduce.
We have a mathematical series here, which generalises out to the following: the odds that the particular DNA that I have would appear starting from N generations ago is equal to
(10^6)^(2^N) times (10^6)^(2^[N-1]) times (10^6)^(2^[N-2]) times … times (10^6)^(2^0)
To simplify that down, this is (10^6) to the power of the sum of a sequence, written as follows:
So k is the number of generations we’re going back, so let’s keep it simple (again) and just go back 10 generations, about 300 years. So if we let k be equal to 10, then our sum becomes 2047, which means that the odds of my particular DNA popping into existence from a mere 10 generations ago is (10^6)^2047, or 10^12282 to one, against.
That bears repeating: the odds of my existence, of my particular combination of DNA, is 10^12282 to one. Yet here I am (and let’s bear in mind that I am underestimating this number by hundreds of orders of magnitude). In order to argue that the author of this particular blog post actually has a genetic sequence of DNA requires far, far more than simply arguing that “that set of DNA is highly implausible”: that argument achieves nothing.
Where plausibility matters is in the comparison of two cases, as mentioned above in the testing example. However, without knowing the possibility of both cases, we can’t simply decide which of the two is more or less plausible. I feel a quote is relevant here:
“How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?” Sherlock Holmes
And that’s the core of it: if one wishes to claim that something was designed, in order to evaluate that claim, we need to know who is claimed as the designer. Logically impossible entities are self-defeating (i.e. self-refuting). Materially improbably entities are, at least, interesting and can’t simply be rejected out of hand (because they’re, y’know, possible). In order for the ID community to be taken seriously, beyond their own community, they need to start fleshing out who or what is the designer.
Meyer, in Darwin’s Doubt, doesn’t do that: instead he calls for the tossing out of Methodological Naturalism. Now… This is kind of a weird response. As I outlined in my review of his book, before we can eliminate methodological naturalism as a method of doing science, we have to demonstrate that all possible natural explanations have failed. But nope, Meyer doesn’t do that, and goes straight to the supernatural.
Well… Intelligent Design has some implications that are likely to discourage his religious (and lucrative) readership. Here’s a diagram.
Here’s the rub: Meyer (and Intelligent Design proponents in general) want to argue that some non-defined “Intelligent Agent” was involved in speciation on earth. And that’s all fine and dandy, but that doesn’t get you out of methodological naturalism. One of the possibilities that they have to completely eliminate (i.e. demonstrate to be impossible) is alien intervention.
This is simply the logical space in which they are placing their arguments: I am not in favour of the alien hypothesis, nor am I in favour of the god hypothesis. So far, the bulk of the experts (i.e. actual biologists) seem to be under the impression that some variation of Evolutionary Theory is going to resolve this issue in favour of the processes hypothesis. As I am not an expert in Biology, I’m going to defer to their expertise (insofar as their methodology is sound). Simply arguing that the processes option is “implausible” doesn’t allow one to immediately leap to the gods option: that has to be demonstrated to be possible, first, then more plausible than both processes and aliens. Jumping immediately to “a god did it” is a demonstration of the religious nature of ID.
Given that I’ve seen a lot of definitions for “god”, and precisely zero of them have been coherent (that is not self-contradictory), I don’t hold out much hope for the proponents of ID. But I do wish they’d be more honest with their arguments.
[Please note that Mathematics, especially Calculus, is not my strong suit. I welcome anyone pointing out the errors in my math. I suspect, however, that the errors are unlikely to affect the actual core point being made, which is not numerical but logical]