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Is Intelligent Design a Bad Scientific Theory or a Non-Scientific Theory?

By Uriah Kriegel - November 10, 2005 12:00 AM

In an election in Pennsylvania this week, voters tossed out eight members of the Pittsburgh school board who wanted Intelligent Design theory to be taught alongside evolution in school. But should Intelligent Design -- the theory that living organisms were created at least in part by an intelligent designer, not by a blind process of evolution by natural selection -- be taught in public schools? In one way, the answer to this question is simple: if its a scientific theory, it should; if its not, it shouldnt (on pain of flaunting the Establishment Clause). The question, however, is whether Intelligent Design (ID) is a scientific theory.

Opponents dismiss IDs scientific credentials, claiming that the theory is too implausible to qualify as scientific. But this reasoning is fallacious: a bad scientific theory is still a scientific theory, just as a bad car is still a car. There may be pedagogical reasons to avoid teaching bad scientific theories in our public schools, but there are no legal ones. The Constitution contains no interdiction on teaching bad theories, or for that matter demonstrably false ones. As long as theory is science and not religion, there is no legal barrier to teaching it. 


To make their case, opponents of teaching ID must show not just that the theory is bad, but that its not science. This raises a much more complicated question: What is science? What distinguishes genuinely scientific theories from non-scientific ones?


In one form or another, the question has bothered scientists and philosophers for centuries. But it was given an explicit formulation only in the 1920s, by Karl Popper, the most important 20th century philosopher of science. Popper called it the problem of demarcation, because it asked how to demarcate scientific research and distinguish it from other modes of thought (respectable though they may be in their own right).


One thing Popper emphasized was that a theorys status as scientific doesnt depend on its plausibility. The great majority of scientific theories turn out to be false, including such works of genius as Newtons mechanics. Conversely, the story of Adam and Eve may well be pure truth, but if it is, its not scientific truth, but some other kind of truth.


So what is the mark of genuine science? To attack this question, Popper examined several theories he thought were inherently unscientific but had a vague allure of science about them. His favorites were Marxs theory of history and Freuds theory of human behavior. Both attempted to describe the world without appeal to super-natural phenomena, but yet seem fundamentally different from, say, the theory of relativity or the gene theory.


What Popper noticed was that, in both cases, there was no way to prove to proponents of the theory that they were wrong. Suppose Jims parents moved around a lot when Jim was a child. If Jim also moves around a lot as an adult, the Freudian explains that this was predictable given the patterns of behavior Jim grew up with. If Jim never moves, the Freudian explains -- with equal confidence -- that this was predictable as a reaction to Jims unpleasant experiences of a rootless childhood. Either way the Freudian has a ready-made answer and cannot be refuted. Likewise, however much history seemed to diverge from Marxs model, Marxists would always introduce new modifications and roundabout excuses for their theory, never allowing it to be proven false.


Popper concluded that the mark of true science was falsifiability: a theory is genuinely scientific only if its possible in principle to refute it. This may sound paradoxical, since science is about seeking truth, not falsehood. But Popper showed that it was precisely the willingness to be proven false, the critical mindset of being open to the possibility that youre wrong, that makes for progress toward truth.


What scientists do in designing experiments that test their theories is create conditions under which their theory might be proven false. When a theory passes a sufficient number of such tests, the scientific community starts taking it seriously, and ultimately as plausible.


When Einstein came up with the theory of relativity, the first thing he did was to make a concrete prediction: he predicted that a certain planet must exist in such-and-such a place even though it had never been observed before. If it turned out that the planet did not exist, his theory would be refuted. In 1919, 14 years after the advent of Special Relativity, the planet was discovered exactly where he said. The theory survived the test. But the possibility of failing a test -- the willingness to put the theory up for refutation -- was what made it a scientific theory in the first place.


To win in the game of science, a theory must be submitted to many tests and survive all of them without being falsified. But to be even allowed into the game, the theory must be falsifiable in principle: there must be a conceivable experiment that would prove it false.


If we examine ID in this light, it becomes pretty clear that the theory isnt scientific. It is impossible to refute ID, because if an animal shows one characteristic, IDers can explain that the intelligent designer made it this way, and if the animal shows the opposite characteristic, IDers can explain with equal confidence that the designer made it that way. For that matter, it is fully consistent with ID that the supreme intelligence designed the world to evolve according to Darwins laws of natural selection. Given this, there is no conceivable experiment that can prove ID false.


It is sometimes complained that IDers resemble the Marxist historians who always found a way to modify and reframe their theory so it evades any possible falsification, never offering an experimental procedure by which ID could in principle be falsified. To my mind, this complaint is warranted indeed. But the primary problem is not with the intellectual honesty of IDers, but with the nature of their theory. The theory simply cannot be fashioned to make any potentially falsified predictions, and therefore cannot earn entry into the game of science.


None of this suggests that ID is in fact false. For all Ive said, it may well be pure truth. But if it is, it wouldnt be scientific truth, because it isnt scientific at all. As such, we shouldnt allow it into our science classrooms. At least thats what the Constitution says.


The writer teaches philosophy at the University of Arizona.


1 Comment

The Final Freedoms
COMPLETELY UNEXPECTED. A real monkey wrench is about to hit both sides in the ID vs Evolution debate and particularly religion is in for difficult times. For a wholly new interpretation of the teachings of Christ, contained within the first ever religious claim and proof that meets all the criteria of the most rigorous, evidential, testable scientific method, is published and circulating on the web. It is titled The Final Freedoms. An intellectual, religious and political bombshell!

It is described by a single Law and moral principle, offering its own proof, one in which the reality of God confirms and responds to an act of perfect faith, by a direct intervention into the natural world, delivering a correction to human nature, including a change in natural law [biology], consciousness and human ethical perception [proof of the soul], providing new, primary insight and understanding of the human condition!

So while proponents of ID may have got the God part right, if this development demonstrates itself to be what it claims, and the means exist to do so, all religious teaching, tradition and understanding of ID are wholly in error, while the proponents of evolution who have rightly used that conception to beat down the credibility of religious tradition, but who have also used it to deny the potential for God, are in for a very rude shock.

However improbable, what history and theology have presumed to be impossible is now all too achievable. The implications defy imagination! No joke, no hoax and not spam.

Review copies of the manuscript, prior to paper publication, are a free pdf download from a number of sites including: and

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