Denis Alexander’s Strawman Just as Silly
|December 13, 2011||Posted by Barry Arrington under Intelligent Design|
In a comment to my last post T.lise picked up on another Darwinist strawman argument. He quotes Denis Alexander saying: “Many people impressed . . . of the huge improbabilities involved in biochemical systems coming into being ‘by chance’. But what the reader might miss easily is that the calculations are based on the whole system self-assembling all in one go . . . But this is tilting at windmills. No scientist believes that this is the way evolution works.”
No ID theorist has ever argued that evolution is impossible because complex biochemical systems cannot self assemble “all in one go.” This is an absurd caricature of the argument from irreducible complexity (IC).
The basic logic of IC goes like this: (1) By definition, evolution can work only in a stepwise fashion wherein each successive step is “selected for” because it has conferred a selective advantage on the organism. (2) an irreducibly complex system is a system which if one part is removed all function ceases. (3) by definition, therefore, an irreducibly complex system cannot be produced in a stepwise fashion. (4) therefore evolution is not capable of producing an irreducibly complex system.
Starting with this logic the ID proponent argues that certain systems are irreducibly complex and therefore could not have been produced by evolution. The bacterial flagellum and the blood clotting cascade are classic examples of such systems.
Again, no ID proponent argues that, for example, the bacterial flagellum could not be produced by evolutionary processes because it could not, like Athena from Zeus’s head, spring into being self assembled in one step.
Now the theory of irreducible complexity is not particularly complicated in principle. A smart guy like Denis Alexander surely knows that ID proponents don’t claim “System X could not have been produced by evolution unless it could be produced all in one go.” So yet again we have an ID opponent apparently afraid to take on ID on its own terms.