Friday, March 25, 2011

Copernican or Anthropic?

The Polish astronomer Copernicus (1473-1543) is generally credited with establishing that the center of the solar system is the sun and not the Earth.* Subsequent astronomical research has shown that our sun is not at the center of our galaxy nor is our galaxy at the center of the universe. Add to this the modern recognition that the universe contains on the order of 100 billion trillion stars, and the result is the idea that the Earth is nothing special, location-wise, ontologically, or in its characteristics. This notion, popularized by the late astronomer Carl Sagan, is often referred to as the "Copernican Principle." This is a misnomer, of course, as Copernicus didn't share Sagan's religious views, and didn't overstate the physical evidence to support an unwarranted metaphysical claim. A better name for this idea--still popular among moderns (especially sci-fi fans who, like Sagan, consider it reasonable to think that the Cosmos is replete with planets hosting intelligent life forms)--is the "principle of mediocrity."

Today, however, anyone affirming the principle of mediocrity would be guilty--as was Sagan in his later years--of committing the fallacy of supressed evidence. During Sagan's lifetime and since, overwhelming evidence contrary to Sagan's view has been accumulating. General relativity has by now become the most rigorously tested theory in all of physics, and its logical product--big bang cosmology--has proved fatal for Sagan's view that "The Cosmos is all there is, or ever was, or ever will be." Moreover, astronomers, chemists, and physicists are continually identifying characteristics of the universe that are extremely fine-tuned to provide for human life. The current understanding--the anthropic principle--has turned the "Copernican" Principle on its head, and we now know (for example) that our sun's place within the galaxy and our galaxy's place within the galaxy cluster are (while not central) exactly what they need to be for life on Earth to be possible. According to astrophysicist Paul Davies...
There is for me powerful evidence that there is something going on behind it all… It seems as though somebody has fine-tuned nature’s numbers to make the Universe… The impression of design is overwhelming.
Stephen Hawking likewise expressed the latest understanding,
It would be very difficult to explain why the universe should have begun in just this way, except as the act of a God who intended to create beings like us.
In days to come, I'll be sharing just a few of the 93+ fine-tuned characteristics of the universe itself (fundamental fine-tuning)and the 154+ characteristics of the galaxy, solar system, and Earth (environmental fine-tuning) that fall within extremely narrow (life-permitting) ranges. If you want to learn more about this yourself, I recommend Hugh Ross' The Creator and the Cosmos, The Privileged Planet by Guillermo Gonzalez and Jay Richards, and the Reasons To Believe website (where updated lists of these characteristics can be found).

*Copernicus' immediate successors, Bruno and Galileo, played important roles in getting this understanding out. Moreover, there is some indication that even Ptolemy recognized ours as a heliocentric system. His system of concentric rings (that is to us moderns Ptolemy's legacy and which brands him as geocentric) may have been his best bet for predicting the locations of the planets given the rather undeveloped geometry of his day.

(I originally posted a version of this post on 16 March 2007.)

Saturday, March 12, 2011

God of the Gaps

[Besides entering my busiest time of year work-wise, I'm teaching one class at the Kilns and another two classes on the internet. What suffers is my time to write new blog posts. So the following is taken from a discussion thread in my internet class, in which I clarify what I take to be the issue with the God-of-the-gaps charge.]

I guess I have a slightly different take on the God-of-the-gaps issue. As I see it, this is not so much something of which Christians generally (and much less practicing scientists who are Christians) are really guilty. Rather, it is an illegitimate charge made against Christians by naturalists. And when naturalists raise this charge, they are generally guilty of several logical fallacies...

1) They are guilty of creating a straw man. While there may be some who easily claim "because God did it" too early in the search for explanations, this is an extreme position and not the one taken by the vast majority of Christians engaged in scientific discussion. When one addresses only the absurd, extreme articulations of his opponents (setting up a straw man that is easily knocked down) instead of addressing the thoughtful, difficult objections made by more moderate opponents, one is being academically disingenuous and logically fallacious.

2) They are guilty of the ad futurum fallacy. (I actually wanted to make up my own name for a fallacy, the "log-in-your-own-eye fallacy," but will stick with a well-recognized name.) But what I mean is that the naturalist is equally guilty (moreso, actually) of engaging in naturalism-of-the-gaps. The claim is that while we don't currently know the natural explanation, give us 75 years and we will. This is a faulty appeal to the future. In good reasoning, one is expected to find the best explanation for all the currently available evidence, rather than appeal to hypothetical future evidence.

3) More fundamentally, the naturalist is guilty of equivocation, wrongly using two significantly different definitions of the 'gaps' being addressed.

The naturalist likes to identify epistemological gaps (gaps of knowledge), and show that historically such gaps have closed. But the more interesting gaps--and those raised by the old-Earth creationist and the proponent of Intelligent Design--are ontological gaps (gaps of existence or being). The naturalist serves his own cause by conflating these two definitions or by ignoring this crucial distinction.

We could discuss (for example) the gap between the existence of a universe and the non-existence of a universe, or the gap between the Edicarean life forms and those of the Cambrian. These are fundamentally gaps of being, not merely gaps in our knowledge. And while the actual gaps involved are unchanging, the epistemological gaps (as we better understand the breadth and suddenness of the Cambrian explosion) are getting larger, not smaller. Perhaps the best example is that of the origin of life. The gap between non-living chemistry and the simplest life is now understood to be much larger than any evolutionary naturalist ever conceived.

So, it is rather uninteresting to note that we ought not be guilty of appealing to the supernatural prematurely, when there is still every indication that a natural (process) explanation will be found (for whatever phenomenon is being studied). But when we are studying origins* questions (rather than process questions), there is every reason to use abductive reasoning, and explanations that involve a supernatural being can reasonably be offered in such cases. This is especially true since only a theistic worldview logically grounds the assumptions that make science worthwhile (as discussed in another thread).

* Failure to differentiate between empirical (process) research and historical (origins) research also serves the scientific naturalist's cause. Whether this represents mere imprecision/naivete or disingenuity on their part I'm never quite sure.

Saturday, March 5, 2011

The Peppered Moth Evidence

From the archives again, the post with which I followed up "Green Toothpicks" about 4 years ago...

[In the last post], I shared about an artificial (and rather poor) illustration of natural selection in action ("Green Toothpicks"). The most famous (and much-cited) example of natural selection in the wild is the changes in coloration of the Peppered Moth, changes that occurred as a result of industrialization in Great Britain. These changes were noticed throughout the 19th and early 20th centuries, as Peppered Moth populations went from being mostly white (with a few melanistic individuals) to mostly dark (with a few light individuals). In the 1950's, Bernard Kettlewell, a British biologist and physician, began a series of experiments that led him to believe that this change could be explained as a result of natural selection. He concluded that the moths were eaten by birds (visually-oriented predators) as they rested on tree trunks during the day. Kettlewell reasoned that before industrialization, light-colored moths were more prevalent because they were better camouflaged on the light-colored (and lichen-covered) tree trunks. But with increasing pollution, tree trunks became darker (and lichens died), light-colored moths were less camouflaged than darker ones, and the phenotype of the population became predominantly that of the dark individuals. This elegant example from the wild remains to this day the classic textbook example of natural selection at work.

Subsequent research has cast a great deal of doubt on this entire scenario. It turns out that Peppered Moths don't normally rest on tree trunks but in the crown of the trees, that researchers (including Kettlewell) released moths by day (even though they are a nocturnal species), that many (not including Kettlewell) in fact pinned dead moths to trunks rather than use live ones in their capture-recapture experiments. In addition, neither the distribution of the various color morphs nor that of the lichens fit the patterns predicted by pollution rates, either during the industrialization or following emission controls (when white moths made a comeback in some regions). The problems unearthed have been so serious that what had been called "Darwin's missing evidence" has been deemed invalid even by evolutionary scientists. (For a summary of these problems, the reader is referred to chapter 7 of Jonathan Wells' Icons of Evolution.) Nonetheless, since evidence for the evolutionary paradigm is so scant, this invalidated tale is still a prominent feature in most modern textbooks (with no mention of its problems).

But again, suppose we ignore (for the sake of argument) the fact that subsequent research has shown that the Kettlewell scenario does not provide the evidence for which Darwinists hope. Let us be generous and grant that perhaps further research will discover a mechanism (consistent with natural selection) that explains the change in Peppered Moths. Then, as evidence for macroevolution, we have the same problem here as we had with the green toothpicks. We have--at the end of the experiment--merely a different frequency of the same phenotypes already present at the beginning. Phillip Johnson has stated the problem well (in Darwin on Trial)...
Why do other people, including experts whose intelligence and intellectual integrity I respect, think that evidence of local population fluctuations confirms the hypothesis that natural selection has the capacity to work engineering marvels, to construct wonders like the eye and the wing? Everyone who studies evolution knows that Kettlewell’s peppered moth experiment is the classic demonstration of the power of natural selection, and that Darwinists had to wait almost a century to see even this modest confirmation of their central doctrine. Everyone who studies the experiment knows that it has nothing to do with the origin of any species, or even any variety, because dark and white moths were present throughout the experiment. Only the ratios of one variety to the other changed. How could intelligent people have been so gullible as to imagine that the Kettlewell experiment in any way supported the ambitious claims of Darwinism?
At least two pitfalls (obstacles to objective truth) can be seen in the Peppered Moth story. First, moth researchers used invalid methods and jumped to wrong conclusions primarily because of an inordinant desire to provide evidence for a popular--but evidentially-impoverished--theory. Second, had their conclusions not been spurious, these same researchers (and their popularizers, including textbook editors still today) have been guilty of failing to see the scalar limitations of their results. Evidence of natural selection working at the level of a species quite simply is irrelevant as evidence for macroevolution.

As a scientist, I only hope that the Peppered Moth may serve as a reminder to avoid these pitfalls long after it has been finally discarded as a significant piece of evidence for Darwinian evolution.