Fairy circles and stone circles

brauer_fig3.jpg</a>brauer_fig6Last week I introduced Dawkins’ term “designoid” with a striking example. These objects have been found in a variety of places, but the most controversial of them come from the site of putative <a href=”http://www.indianexpress.com/ie20020117/top6.htmltarget=”new”“>neolithic habitations in the present Gulf of Cambay, India. The “artifacts” have been used to bolster the <a href=”http://www.grahamhancock.com/underworld/cambay3.php?p=1 target=”new”“>controversial theory</a> that a highly developed civilization existed at the site nearly 10,000 years ago.

Paul Heinrich of the Louisiana Geological Survey addresses these claims: <blockquote>Without the benefit of any detailed peer-review or publications in scientific journals, much has been made about the significance of these alleged artifacts from the bottom of the Gulf of Cambay. The significant problem with both press releases and web pages that describe these items is that they provide little, if any, hard data that authenticates the identification of these items as valid artifacts or bones. Despite the giddy claims of either a “Lost” or an ancient Indian civilizations as described in Vedic literature, some caution needs to taken by the various parties in the making the claims being made about these items.</blockquote>

Heinrich presents examples of natural carbonate concretions from Endako, British Columbia as a convincing counterargument to such claims. These items are not manufactured, but instead are the results of precipitation around either the burrows of marine invertebrates or calcified root casts.

As with most designoids, the only thing allowing a design inference for these concretions is the ignorance of the natural processes that formed them.

brauer_fig7One of my favorite designoid examples was the subject of an article in Science and an extensive thread on ISCID. These “stone circles” are patterns caused by heaving in the permafrost where they are found, and the details of their formation are well enough understood that the process can be modeled numerically. On ISCID Paul Nelson addressed the issue of stone circles and the ability of Dembski’s “Explanatory Filter” (EF) to determine whether or not they were designed. Now, the obvious question arises: how does the EF categorize stone circles? “andyg” asked that question in the first response to Nelson’s post: “if you put the stone circles thorugh Bill’s filter, what answer do you get?”

Nelson’s answer was rather evasive, I’m afraid. He responded: “Some commentators offer patterns like naturally-occurring stone circles as challenges to the explanatory filter, as if Dembski (or other design theorists) had never considered such patterns as possible counterexamples. That’s naive.”

So Dembski (and others) have considered stone circles as “possible counterexamples.” And what has been the conclusion of this consideration? Only that “It’s hard to use stone circles (i.e., sorted pattern grounds) now as a test of the filter, for obvious reasons.”

Now why should this be? Why is it that a design-detection filter cannot detect whether or not a simple geometrical pattern in the earth is the product of design? It turns out that the “Explanatory Filter” fails beacuse we know of naturalistic mechanisms that cause stone circles. In other words, the EF can only be applied to phenomena for which we have not (yet, perhaps) found a naturalistic mechanism. The EF applies only to instances where gaps remain in our knowledge. As those gaps disappear, design inferences might presumably disappear as well.

This notion directly contradicts Dembski’s assertion that the EF results in no false positives, that any positive determination of design will be correct. Nelson himeslf recognizes this:

Might one mistakenly attribute a pattern to design, when a perfectly adequate natural cause exists? Of course. Such errors have happened in the past, and will happen again. But Dembski has never claimed otherwise. We never reach a state of scientific knowledge where false positives are impossible. Nevertheless, humans do infer design, and the great majority of these inferences are remarkably stable over time -- as stable and reliable, in fact, as the very best knowledge in science. That says to me that the worry about false positives should not rise any higher in one's consciousness than the ordinary caution one takes in making any inference.

More problematic is the steadfast refusal of believers in the EF to apply it to real world examples, or to supply any algorithm for others to apply it. Is a circle of stones “specified?” We don’t know, and we aren’t told how to find out. Is the probability of a pattern arising by chance dependent on the history of the pattern, even if we don’t know that history? It’s not clear. In short, there is no set of objective criteria for applying the filter. This makes it a useless tool for scientific investigation.

brauer_fig8A related instance of apparent design can be seen in the “fairy circles” of Namibia. These are bare patches of soil for which there are currently no naturalistic explanations. Researchers into the phenomenon have ideas about possible causes, but concede that none of them are adequate and that “…for the moment, we’re left with the fairies” as an explanation.

Is this a concession of design? And did the researchers come to the “fairy” conclusion by applying the EF? Not exactly. As with many situations where the cause of a pattern is not yet known, design provides a convenient (if facetious) placeholder for our ignorance.

In contrast to the case of the stone circles, the cause of the fairy rings is not yet known. So we might expect that the EF is useful for determining if they were designed. I look forward to seeing how the EF might be applied to these patterns, but I’m not holding my breath. I suspect that the answer will come back that “we don’t know enough about these rings to apply the filter.”

It looks more and more as if the “Explanatory Filter” provides nothing except a gauge of its advocates’ belief that an object is designed.