Tuesday, December 22, 2009

Darwin's Dilemmas: Essence Precedes Existence--Part 5

As we've seen in this series, evolutionary theory and its existential nature is refuted by the fossil record and by our newfound insight into the development of an organism. Whereas evolutionary biologists illustrate the history of life using a "tree of life", the fossil record--if viewed in the way evolutionary biologists view it--illustrates the history of life instead as a "forest of life", a great many kinds of animals leaping into existence all at once with no common ancestry. Whereas random mutations during the copying of DNA are proposed as the mechanism by which genetic information increases over time, we now know that a second, mutually dependent source of information exists containing the instructions for assembling the protein parts defined by DNA, and this information is not in the DNA itself. These discoveries demonstrate that, unlike existentialism's "existence precedes essence," when it comes to life, "essence precedes existence."

How, then, do we "put the pieces together?" Can legitimate science point us to an alternative explanation? Is any appeal to a supernatural cause by definition unscientific?


Critics of intelligent design often accuse its advocates as "not doing science." In Stephen Meyer's book, Signature in the Cell, he recounts that "reporters kept repeating the same criticism, namely, 'ID advocates aren't really scientists, because they don't do any experiments of their own'" (p. 138). In a recent debate between intelligent design advocates (including Meyer) and its critics (listen here), one of the design opponents said he was not aware of any intelligent design scientists who have labs and do experiments, implying that laboratory experimentation is the only way to properly "do science."

In the debate, evolutionary proponent Michael Shermer argued, "There's only two explanations...to answer the question of what's the origins of life or the diversity of life: one, science; two, everything else." He continued:

The problem is that by invoking something that is by definition not testable, there's no experiment we can run. You're now off the page of science. So, by invoking some kind of extranatural, supernatural, supranatural, paranatural--something beyond the natural, there's nothing we can do with that.

His partner, Donald Prothero, continued:

As Michael just said, we're talking about testable hypotheses...We cannot resort to supernatural explanations. It's not because we're antireligious...It's because religious ideas are simply not testable. There's no way to say, "God did it," and then find a test that works.

So, evolutionary scientists demand that the only way to address the question of the origins of life in a scientific manner is through a) laboratory experimentation, and b) testable hypotheses. Because, they claim, appeals to supernatural causes are by definition untestable, they are not scientific.


In April of 1953, J. D. Watson and F. H. C. Crick revolutionized biology when their article, "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid," appeared in the journal Nature. In their article, the pair revealed the molecular structure of DNA, winning a scientific race that had been going on for years. Yet, their work was not primarily the result of their own laboratory experiments. As Meyer put it in Signature, "While others approached the problem methodically, steadily gathering data in their labs, Watson and Crick behaved more like gumshoe detectives, heading from one place to another looking for clues to help them weigh the merits of competing hypotheses" (p. 72).

This approach is not unique among scientists throughout history. As Meyer notes in Signature:

Many of the great discoveries in science were achieved not just by experimentalists who produced new factual knowledge, but by theoreticians who taught us to think differently about what we already know. Examples of this kind of scientific work leaped to mind: Copernicus's De Revolutionibus orbium coelestrium, Newton's Principia, and the papers Einstein produced in his annus mirabilis...Charles Darwin also did little experimental science...his masterpiece, On the Origin of Species by Means of Natural Selection, contains neither a single mathematical equation nor any report of original experimental research. Yet he formulated a great scientific theory. He did this by drawing together disparate lines of observational evidence and presenting an argument for a novel interpretation of that evidence. (p. 139)

Proper science does not by necessity include one's own, personal laboratory experimentation. Instead, legitimate science often involves reasoning like a detective, considering multiple suspects, weighing clues and excluding suspects that could not have committed the crime, eventually narrowing in on the one suspect whose involvement is pointed to by the weight of the evidence.


One can see a distinction between these two scientific approaches when one looks at what might be called "historical sciences" versus what might be called "experimental sciences." Experimental scientists, such as chemists and physicists, hypothesize about how things work now, and then test those hypotheses through laboratory experimentation. Historical scientists, on the other hand, such as geologists, archaeologists, paleontologists, cosmologists, and yes, evolutionary biologists, look at multiple competing attempts to explain the past, weighing the merits of each, excluding those explanations which do not fit the evidence, and narrowing in those explanations that do fit the evidence.

In History of the Inductive Sciences (1837) and The Philosophy of the Inductive Sciences (1840), scientist and philosopher William Whewell explained the distinctions between these two kinds of sciences. Instead of trying to establish universal laws by which nature operates, the objective of historical scientists is to determine ancient conditions or past causes. Rather than studying "forces that are permanent causes of motion, such as gravitation attraction," historical scientists study "causes that have worked their effects in temporal succession." And in attempting to reconstruct those "ancient conditions," historical scientists "calculate backwards" and determine what has occurred in the past based on known cause-and-effect relationships in operation in the present.

No chemist, physicist or biologist claims that historical scientists are "not doing science." The dictionary defines geology as "the science that deals with the dynamics and physical history of the earth;" archaeology as "the scientific study of historic or prehistoric peoples and their cultures;" and paleontology as "the science of the forms of life existing in former geologic periods" (emphasis mine in each case). But scientists in these fields do not make hypotheses that can be tested through laboratory experimentation. Instead, they look at the present effects of past causes; they weigh competing attempts to explain what happened in the past based on what we see today.

The hypotheses of geologists, archaeologists and paleontologists, despite being untestable through laboratory experimentation, are not untestable altogether. They're merely tested in a different manner. Historical scientists look for the best attempt at explaining what occurred in the past resulting in what we see today. Given the effects of some event or condition in the past, they look at what causes, known to produce similar effects, could have occurred in the past, and exclude causes that cannot account for those effects.


So while experimental scientists test their theories by predicting what will happen and validating or invalidating their hypotheses in the lab, historical scientists test their theories by comparing the explanatory power of competing theories. The claim made by critics of intelligent design theory, that it is untestable and thus not science, is refuted by some of the very heroes of evolutionary science like Watson, Crick, and Darwin himself, as well as by historical scientists like geologists, archaeologists and paleontologists.

How, then, can this legimiately scientific approach and its test of the explanatory power of competing theories be used to determine the cause of the diversity of biological life we see today? Stay tuned.

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