Swamidass & Behe Both Take the Wrong Approach

I left the following comment on the Peaceful Science Facebook Page but thought it might get more traction here:

"I don’t think either you (Josh) or Behe are correct about the way you approach this topic.

The issue is that the question seems to always be framed as ‘has ID produced sufficient evidence to demonstrate that certain structures cannot evolve?’ And, the implication is that, if they haven’t (and they have not,) then it is safe to assume that these structures could evolve. The burden of proof, however, is not on ID. Evolution is a theory that claims to offer a solution to biological complexity, and, to adequately do this, it must address even the more difficult aspects of this complexity.

A big problem with Behe is that he always focuses on microbiology, because that is his area of expertise. At the molecular level, however, we’re dealing with limited complexity, with extremely large populations and with very high reproductive rates. So it is conceivable that something like the flagellum might have evolved, in spite of it’s interlocking parts, through sheer brute strength (like a computer cracking a difficult password by trying every possible combination.) The plausibility of this decreases drastically at higher levels of organization where the biological machines mirror the complexity of some of the most complex man-made machines (we were able to send people into space and create computers the size of one’s hand before we could make bionic eyes to restore sight to the blind).

What poses a challenge when it comes to the evolution of higher order biological machines is the nature of the evolutionary mechanism itself. Random mutations, on their own, are not sufficient to explain the complexity of life. It would be similar to someone trying to get somewhere by taking a step forward every time they flip a coin to ‘heads’ and a step back for ‘tails.’ Because of this, natural selection plays a critical role in the evolutionary process. When it comes to biological machines, however, it is not evident that every change will produce a benefit that can be selected, given the nature of how machinery in general works. It is conceivable that some changes would be beneficial, others neutral and still others detrimental, at least temporarily, while improvements to the machinery take place. Changes that are neutral, however, leave nothing for natural selection to act upon, returning things to that state of randomness, while, temporarily detrimental changes would be actually opposed by natural selection. So we would need to have a clear understanding of the evolutionary pathway of such machines to determine if they could evolve in the time available.

So in essence, this question should be looked at as having three possibilities:

  1. There is sufficient evidence that biological machines could NOT have evolved? (probably not)

  2. There is sufficient evidence that they COULD have evolved.

  3. Otherwise, the jury is still out, meaning that there is still room to consider alternative possibilities (most likely the case in my opinion)

Anyone that has tried to argue for #2 that I have seen, has used one of the following arguments:

a. These structures very likely did evolve, because the evolutionary mechanism is the only viable mechanism we have so there is no other way for them to have gotten here (begs the question)

b. Intermediary stages for biological machines can be found in the fossil record (this assumes that intermediaries would not exist apart from evolution)

I personally have never seen anyone make a positive case that these structures could evolve that properly takes into account the level of complexity we’re dealing with, which is why I think possibility 3 above is still most likely the correct one. Does this prove evolution wrong? No. But it does mean that there is room for other options."

Here’s one: Nilsson D., Pelger S. A pessimistic estimate of the time required for an eye to evolve. Proceedings of the Royal Society of London, Series B 1994; 256:53-58.

Further, you misunderstand the nature of fossil evidence. Intermediate fossils fit within a framework of common descent. Common descent and ID are compatible, but the intermediates are evidence that a viable pathway exists between forms. That falsifies some versions of ID, which claim that intermediates would not be functional. One can of course never eliminate ID with evidence, since there’s no way to distinguish random mutation or selection from planned mutation and mandated fixation.


Sorry but no one in science uses that argument for evolution. Evolution is accepted because the overwhelming quality and quantity of positive evidence it has amassed in the last 160+ years. Other ideas like ID-Creationism or “last Thursday-ism” are rejected not because “there is no other way” but for their complete lack of positive evidence. The scientific community is indeed open to alternatives ideas to evolutionary theory. They just have to explain the empirical evidence in a better, more consilient manner and make better predictions than evolutionary theory does. To date nothing has come close.


Raising hand - I beg to differ! I keep saying that’s all I see and no one’s listening. Anything that isn’t begging the question is called pseudoscience and mocked.

You say a lot of things that are orthogonal to reality. The “alternatives” offered by woo merchants like ID-Creationism and last Thursday-ism are indeed pseudoscience and have not produced one iota of scientific positive supporting evidence.


It’s nice that you wanted to prove my point.

Option 4 is that the structure is evidence we can infer a mechanism as powerful as a mind is behind the universe (which this structure is a part of) we are observing. We are observing purposely arranged parts in both the DNA and protein structures.


No Bill, we see function, not purpose. Amazing after all this time you still don’t understand the difference.


Are you claiming that you see meaningless function?

PURPOSELESS Bill, not meaningless. Purpose implies conscious intent for which there is no evidence in the evolution of biological forms. Purpose can produce function but not all function is a result of purpose.


There are always going to be features and structures that we don’t know the exact origin of. No theory is complete, and no theory in science can explain every single observation within its purview.

The scientific community has overwhelmingly accept evolution because of just how much it has explained. The theory of evolution has explained the nested hierarchy, the mixture of features in fossils, the pattern of shared ERV’s in primate genomes, the pattern of substitution mutations that separate species, the changing pattern of sequence conservation across exons and introns, the overall divergence of sequence between species, and so much more. ID has no explanation for these observations other than common descent and evolution.

The real issue is that Behe looks at the origin of structures that originated in deep time which limits the phylogenetic information that can be brought to bear. Also, his entire argument is based on his own incredulity and baseless claims of improbability. We don’t know exactly how the flagellum came about . . . and that’s it. You can’t jump from a point of ignorance and then claim it disproves evolution. If I can point to a rock and a geologist can’t tell me the exact blow by blow account of how that rock came to be does that mean the rock was made by magic, or that all of geology is falsified?

What would the research for the alternate possibilities look like? What experiments could they run?


Purpose is the word used in Behe’s argument.How do you support the claim that something is purposeless. I believe by the use of the word purpose Behe is simply saying that he can infer a reason for the function observed.

Example: What is the purpose of the bacterial flagellum motor?
Answer: To control the movement of the bacteria.

The purpose can be inferred from observing the function. The function of the motor on the other hand is simply to rotate the flagellum.

Part of the use of Inference in science is making a conclusion from an observation as Behe was doing when he observed the flagellum.

The ultimate power of the design argument is that we can infer intelligent cause of the universe from the empirical data collected inside the universe.

We know Bill. That’s how we know he is wrong. He hasn’t established any conscious intent in the formation of any biological feature, just claimed it with zero evidence.

(facepalm) No Bill. The function of the flagellum is to provide movement. You’re still confusing function for purpose.

No Bill, it can’t. Just like it’s ridiculous to claim the purpose of the human nose is to hold eyeglasses.


Unfortunately, it isn’t done through empirical means. “It looks designed” is a subjective opinion, not an empirical observation.

It’s not the purpose of science to establish. It’s the purpose to make inferences base on observation.

You may disagree with his inference but that does not take away his ability to make the case for his inference.

The function of the flagellum motor is to rotate the flagellum. When you dropped motor from my argument you created a straw man argument.

This assumes it has a purpose.

Can some entity do something, can it have an effect, that it was not intended to do?

This is a good point. The question should be modified to remove any assumption from it in order to make the inference.

Behe hasn’t made a scientific case to anyone. He keeps finding new ways to say “looks designed to me!” without providing a shred of scientific evidence. Only real suckers desperate to prop their religious beliefs get taken in by his empty rhetoric.

That’s right Bill. The function, not any consciously intended purpose.


Agreed. I think it is very difficult to come up with a set of uncontroversial premises that leads to such a conclusion.

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Yes, I agree it would be difficult to make a statement about purpose containing uncontroversial premises.

I do however think we can generate a question that allows for an inference to be made that does not assume purpose. The question has to allow for purpose to not be inferred. The question is if Behe’s use of the word purpose is reasonable?

It is pretty clear to me that the flagellum motor has both a function and a purpose that can be inferred. I don’t see any real reason to go back to Mike and suggest to him to replace the word purpose for the word function other than people arguing against design making assertions.