Thoughts in a Haystack

The Discovery Institute is bucking for another entry in Glenn Morton's list: "The Imminent Demise of Evolution: The Longest Running Falsehood in Creationism," right along with its director, Stephen Meyer, in his about-to-be-released book, Signature in the Cell: DNA and the Evidence for Intelligent Design.

Actually, they are after even bigger fish: scientific materialism. Methodological naturalism, whereby science assumes that natural phenomena have natural explanations -- that has so advanced human knowledge over the last 500 years -- is said to be crumbling, leaving us with ... what? According to Meyer, it is "intelligence that stands outside nature and directs the path life has taken." If that isn't God, I'll also eat John Wilkins' epistemological hat.

Since we are, if Meyer is right, allowing supernatural explanations into science, let me exercise my extrasensory perception and predict what the major themes of the book (which I obviously have not read) will be:

There will be an analogy to human design, particularly analogizing DNA to computer software;

There will be an argument that any inability of science to explain the origins of biological "information" demonstrates design;

There will be an argument claiming that any inability of science to explain the origins of DNA disproves evolution.

Okay, so maybe I'm not psychic, since Meyer's own webpage shows that he is making all those arguments in the book and they are, contrary to the DI's claim, hardly a "unique, new argument for intelligent design."

There is one claim that Meyer has made before but is not as common as the others:

Drawing on data from many scientific fields, Stephen Meyer formulates a rigorous argument employing the same method of inferential reasoning that Darwin used.

The cheese in the larder has disappeared, apart from a few crumbs;

Scratching noises were heard coming from the larder last night;

Therefore, the cheese was eaten by a mouse.

It is obvious that this inference is non-deductive: the premisses do not entail the conclusion. For the cheese could have been stolen by the maid, who cleverly left a few crumbs to make it look like the handiwork of a mouse. And the scratching noise could have been caused in any number of ways - perhaps they were due to the boiler overheating. Nonetheless, the inference is clearly a reasonable one. For the hypothesis that a mouse ate the cheese seems to provide a better explanation of the data than do the various alternative explanations. After all, maids do not normally steal cheese, and modern boilers do not tend to overheat. Whereas mice do normally eat cheese when they get the chance, and do tend to make scratching sounds. So although we cannot be certain that the mouse hypothesis is true, on balance it looks quite plausible: it is the best way of accounting for the available data.

... Darwin argued for his theory of evolution by calling attention to various facts about the living world which are hard to explain if we assume that current species have been separately created, but which make perfect sense if current species have descended from common ancestors, as his theory held. For example, there are close anatomical similarities between the legs of horses and zebras. How do we explain this, if God created horses and zebras separately? Presumably he could have made their legs as different as he pleased. But if horses and zebras have both descended from a recent common ancestor; this provides an obvious explanation of their anatomical similarity. Darwin argued that the ability of his theory to explain facts of this sort, and of many other sorts too, constituted strong evidence for its truth.

[O]ne issue clearly demands more attention. If we want to use IBE, we need some way of deciding which of the competing hypotheses provides the best explanation of the data. But what criteria determine this? A popular answer is that the best explanation is the simplest or the most parsimonious one. Consider again the cheese-in-the-larder example. There are two pieces of data that need explaining: the missing cheese and the scratching noises. The mouse hypothesis postulates just one cause - a mouse - to explain both pieces of data. But the maid hypothesis must postulate two causes - a dishonest maid and an overheating boiler - to explain the same data. So the mouse hypothesis is more parsimonious, hence better. Similarly in the Darwin example, Darwin's theory could explain a very diverse range of facts about the living world, not just anatomical similarities between species. Each of these facts could be explained, in other ways, as Darwin knew. But the theory of evolution explained all the facts in one go - that is what made it the best explanation of the data

The idea that simplicity or parsimony is the mark of a good explanation is quite appealing, and certainly helps flesh out the idea of IBE. But if scientists use simplicity as a guide to inference, this raises a problem. For how do we know that the universe is simple rather than complex? Preferring a theory that explains the data in terms of the fewest number of causes does seem sensible. But is there any objective reason for thinking that such a theory is more likely to be true than a less simple theory? Philosophers of science do not agree on the answer to this difficult question.

Link - Posted by John Pieret @ 10:52 PM