Ross's chapter 16 is devoted to constructing outlandishly large numbers for the improbability of individual cells or biomolecules occurring by chance. And then he concludes that these events are so improbable that a God must have miraculously intervened to create these things. For example, he claims, following Harold Morowitz who is not a creationist, that the probability of a single cell forming randomly from its constituent parts is 1 in 10 to the 100,000,000,000. Surely a cell forming from basic constituents randomly is highly improbable, so it's a good thing that no one thinks any such thing happened. (Ross cleverly uses the phrase "under ideal natural conditions" [p. 138] as though he is not arguing from the random assembly of parts but from any possible natural assembly of parts.) Instead, those, such as Morowitz, who are interested in this issue think that smaller biomolecules formed from a prebiotic soup by small stages, and, that these molecules then formed increasingly complex molecules until a simple self-replicating molecule formed from them. This self-replicator would then provide the basis necessary for evolution to get going, and real living organisms could then result.
This is standard creationist claptrap, implying that evolution, biogenesis, or whatever could only have occurred randomly over some improbably large item. I could argue, in similar fashion, that Hugh Ross's existence requires the direct intervention of a divine being. Suppose I imagine that all Hugh Ross's constituent atoms were sitting around in a prebiotic soup and suddenly, with a flash of lightning, they spontaneously assembled themselves into Hugh Ross. I'll conservatively estimate the probability of this happening as one in a googol. (See, I can make up probabilities too.) Since this probability is so fantastically low that this could never occur randomly in the course of a billion universes, I think it's safe to say that Ross was created by a divine being in his present form. Now, I suppose Ross might say that he has a "causal history" and "genealogy", that he did not arise by random chance from a set of unrelated constituents, that his genesis resulted from a series of causal stages of earlier beings whose existence we can know from the "traces" they have left behind. Of course, there is a difference between the Spontaneous Ross Generation case and the living-cell case in that we do not as yet have any way to show directly that these causal intermediaries existed on earth before the first fossils formed. But we can make inferences about the nature of that early earth and construct laboratory experiments to test these inferences. That, of course, has been done, for example, in the case of the Stanley Miller and Harold Urey experiments. These experiments are not the end of investigation of this question, but they provide a start to such investigation, and they show conclusively that it is possible for bio-molecules to arise from some form of prebiotic soup by entirely natural means.
What can Ross say about such cases? Apparently, at some step in the process from ammonia to RNA bases, or from RNA bases on up to the cell, one or more step is physically impossible. Perhaps Miller cheated, or God intervened in Miller's (or others') laboratory. And the same thing occurred in every confirming experiment.
The point is that we have seen that complex biomolecules can arise from conditions that plausibly could have obtained on earth, yet Ross's position is that this is effectively impossible because its probability is vanishingly small. Ross's position here is simply falsified by the experimental evidence; there must be an error in his probability calculations (or, more specifically, one of his key assumptions) because in fact something he claimed to be impossible actually occurred. It is clear what the problem is. Ross assumes that large scale assembly must occur purely at random from the smallest constituents (much like our Ross arising spontaneously from his constituent atoms) when it is more likely that life arose by a series of stages each of which, plausibly, could arise from the increasingly complex molecules of the stage before. It is not really surprising, then, that Ross never mentions the Miller-Urey experiments in a chapter devoted to exactly the problem they set out to investigate. Actual evidence would undermine the point he is trying to make.
I am not asserting that there are no problems with the Miller-Urey experiments (such as the existence of both right and left-handed isomers that Ross emphasizes) or later experiments, or that no further investigation is necessary. All I am saying is that increasing complexity of macromolecules is possible given initial conditions that might have obtained on earth, so there is no compelling reason to think we could not have ultimately derived from a prebiotic soup. And Ross's claim that this is impossible is not plausible.
Monday, November 30, 2009
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