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Dumbing down intelligent design

'No practical biologist interested in sexual reproduction would be led to work out the detailed consequences experienced by organisms having three or more sexes; yet what else should he do if he wishes to understand why sexes are, in fact always two?' -- R. A. Fisher (1930).

The scientific definition of "theory" is very different from its popular meaning of "wild speculation." The Theory of Evolution, like the Germ Theory of Disease, or the Atomic Theory that forms the foundation of chemistry, is solidly based in observations and experiments. The "theoretical" part, in each case, is a collection of well-tested principles that make sense of the masses of data and let us make predictions. For example, Germ Theory led to measures to limit the spread of AIDS, where the Divine Punishment Theory failed. The Theory of Evolution has been equally successful, with slowing the spread of insecticide resistance in insect pests among its recent contributions.

But is there a place for speculation in biology? I think there is, so long as we don't confuse it with fact or well-grounded theory. For example, life as we know it uses nucleic acids for heredity and makes much of its cellular machinery from proteins, but can we think of other possibilities? If so, can we design experiments that would detect such alien lifeforms, if they exist, on Mars or perhaps even on Earth?

Similarly, what if some alien life-form -- any sufficiently advanced life-form is indistinguishable from a god -- has intervened in evolution here on earth? Could we develop quantitative methods to measure this effect, as we now do for natural selection and gene flow? Or, suppose we had an old bloodstain purported to be from a demigod; could we extract DNA, look for alleles that don't match anything in the human genome, and (if we found any) clone them into E. coli? A gene for smiting might have military applications. Perhaps others could be reverse-engineered for flood control. (Hey, mixing religion and science was their idea, not mine!)

The topics in the last paragraph may be too speculative to be competitive for tax-supported research grants -- success rates for many NSF programs are around 10% -- but private foundations could certainly fund such research, if they chose. To be taken seriously, however, researchers looking for evidence of intelligent design would need, as in all of science, to design experiments that have the potential to disprove their hypotheses, if those hypotheses turn out to be wrong. And they would need to publish their results in peer-reviewed journals, so that other scientists have a chance to catch any logical fallacies or methodological problems they may have missed.

This is what the advocates of intelligent design have failed to do. Put all the intelligent design papers ever published in a pile and you don't match the productivity of one good graduate student. Whining, as in the much-discussed film, Expelled, is no substitute for science.


Nice blog. I like to keep up with scientific findings in biology so I'll be back to read more.

I would love to see some of these experiments performed. And I'm sure the CIA would be interested in the whole omnispresence thing.

I think this is a point that many creationists completely fail to understand. If they had solid evidence of a creator, I (and many like me) would become believers. Simple as that. I'm not an atheist because I'm just contrary like that. It's because I haven't seen a shred of evidence to support any other position.

The created-the-universe-billions-of-years-ago and extreme-rendition-after-death ("WE don't torture") claims may be untestable (in contrast to young-earth), but intervened-in-evolution seems like a researchable hypothesis. A human gene with no homolog in other apes and a clear link to altruism towards nonkin would certainly be suggestive of external intervention, perhaps using a engineered viral vector. But, just as creating life in the lab wouldn't prove that life on earth was also designed -- actually, a commentator tried to claim that the fact that we haven't done this yet is somehow evidence for creation -- a result consistent with a hypothesis strengthens it but does not prove it.

New paper out in Nature attacks intelligent design - interesting for you?


Yes, thanks!

The creationism vs Darwinism debate becomes a lot clearer if you have a clear and accurate idea of exactly what a proven scientific theory actually looks like. In a scientific theory you ignore vast quantities of detail to get a useful simplified model of part of reality. There are four parts to a theory. The first is a clear exposition of the model and its mapping to reality. Peer review is useful in ensuring this part is done correctly. Then there is a demonstration that the theory is applicable, in two parts - a set of extrapolations or predictions from the theory and sets of measurements that can be compared to the predictions. The process of making measurements involves care in ensuring that extraneous details do not significantly bias the measured values and again peer review is useful in ensuring that the processes of computing predictions and measuring results has been done correctly. However, and this is crucial, the comparison of prediction and measurement is not a peer-review process. Any science consumer may, and indeed is entitled to, make the comparison between prediction and experiment themselves and draw their own conclusions. This point is obvious in cases like eclipse predictions and geological predictions of minerals, but is generic. The final requirement, since there is as yet no theory of everything, is a list of the details in reality that are warnings that the theory will fail - if distances are far less than the radius of the earth then a simple flat earth model will work, if energies are well above Planck's constant and speeds are very much less than light then Newtonian physics will work -etc.

With this understanding you can easily see why creationist ideas fail as science. Firstly the derivation of a prediction requires a precise definition of the intent and constraints of a creator - both of which are claimed to be unavailable by creationists. Secondly, at least for creationists of the Judao-christian persuasion, there is an attribution of infinite powers to the creator and any attempt to make a model with infinite values quickly leads to a situation where all calculations have only three possible values - something multiplied by infinity - infinity, something divided by infinity - zero, and something both multiplied and divided by infinity - indeterminate. It is not possible to get theoretical values if these three are the only available numbers - ask any theoretical physicist, they have had this problem.

The problem issue with this analysis, as far as Darwinists is concerned, is that the same analysis destroys the claims made about neo-Darwinism. There are substantial numbers of cases where neo-Darwinian predictions have no resemblance to measured values. The clearest examples arise for situations where there is an increase in the number of genes in a genome. This leaves two options - accept that neo-Darwinism does not constitute a proved theory of evolution or make explicit the exceptions where the theory does not work. Somehow a statement that we evolved as a result of untold numbers of small neo-Darwinian changes and 30,000 inexplicable large non-neo-Darwinian changes, while true, does not have the impact of the usual lie.

The really strange fact is that evolution is such a ubiquitous phenomenon that there is a lot of data available and any half-way competent biologist who took the attitude "here is some data on evolution, what can I learn from it" instead of the trained response "here is some data on evolution, how can I fold, bend, spindle, mutilate or hide it so as to leave no evidence that neo-Darwinism is inadequate" would be able to work out the actual mechanism behind species formation over a long weekend.

It is a tough task for creationists to package intelligent design as science, since intelligent design implies supernatural causes and the scientific culture and method do not accept supernatural causes. Science as it is actually practiced only studies natural physical processes.

There is a larger problem, and that is that since science cannot or does not examine supernatural causes or theological explanations for evidence, it cannot look at both sides of this issue without bias, which is required I think for proof.

Your comments make no sense to me.

1) Peer reviewers always compare predictions to measurements; about 10% of papers that I review have a discrepancy between results and conclusions, requiring the latter to be modified. Furthermore, "science consumers" are free to critique all aspects of published papers (via blogs, letters to the editor, etc.), pointing out any problems reviewers may have missed.

2) Scientific theories are never "proved." Even those that have survived many tests are accepted only provisionally; new data might require modification. See our "Strong Inference" paper (link below) for details:

3) If you have an unambiguous example of data that are inconsistent with mainstream evolutionary theory (which I'm afraid you may not understand clearly), why are you wasting your time posting comments that only a handful of people will ever read? Send it to Science or Nature!


If "supernatural" means "impossible to study scientifically", then by definition science can't study that which science can't study.

But if "supernatural" simply refers to the actions of a being or beings much more intelligent and powerful than humans, then science is a more useful tool than mindless reliance on old stories. If I thought that some external power might have intervened in any significant way in the evolution of humans or other species, I would be looking for evidence of such intervention, rather than whining. See comment #3 above for an example of the sort of evidence I would look for: a human gene with no homolog in other apes (so perhaps introduced by a supernatural Designer) and a clear link to altruism towards nonkin or perhaps religiosity.

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