Review Of The Seventh Chapter Of Signature In The Cell by Stephen Meyer
ISBN: 9780061894206; ISBN10: 0061894206; Imprint: HarperOne
The distinction between historical and experimental science is one that extends back over the centuries and at its core seems easy to grasp. Whereas historical science has as its focus events that have defined the history both of our planet and larger cosmos, experimental science has its eye on the current operation of nature.
The 19th century philosopher William Whewell coined the term ‘palaetiological sciences’ to describe those fields of science, such as geology and paleontology, that have a historical perspective (1). Whewell’s broad application of the term shone through in his two great works, his History of the Inductive Sciences and his Philosophy of the Inductive Sciences (1). Immanuel Kant used a similar distinction contrasting those sciences that describe “relationships and changes over time” with those that deal with the “empirical study and classification of objects…at present” (2).
As part of their analytical process, scientists routinely assess the validity of competing hypotheses to determine which best explain the data they have at their disposal. The late Cambridge philosopher Peter Lipton formally defined such a process of validation in his book Inference To The Best Explanation (3). Put simply, Lipton considered the best explanation for the occurrence of a natural event as one that obviously best identifies a likely cause. Lipton’s formalization rode on the back of 19th century geologist Thomas Chamberlin’s ‘method of multiple working hypotheses’ (4) and provided an improvement over Charles Peirce’s abductive reasoning- the process through which an established rule is used to explain a tangible observation (5).
Abductive reasoning would have us say that given a rule such as “If it rains the grass is wet”, the occurrence of wet grass must invariably lead to the conclusion that rain had fallen at some moment in the past (5). Nevertheless Peirce was quick to identify an inherent fallacy in such a thread of logic- a fallacy known amongst philosophers as the ‘affirmed consequent’. According to one review:
“Affirming the consequent, sometimes called converse error, is a formal fallacy committed by reasoning in the form: If P, then Q. Q. Therefore, P. Arguments of this form are invalid in that [they] do not always give good reason to establish their conclusions, even if their premises are true.” (5)
In the above illustration, the fallacy is all too evident since rain is quite obviously not the only causal agent that waters our lawns (summertime sprinklers and hose pipes stand out as self-evident alternatives!). The question that naturally follows is, given numerous causally adequate explanations, how might one go about deciding which supplies the greatest explanatory power?
One way is to resort to vera causa (“causes now in operation”) as Darwin did when he used animal migration behaviors to explain common descent. According to Darwin “the simplicity of the view that each species was first produced within a single region captivates the mind. He who rejects it, rejects the vera causa of ordinary generation with subsequent migration, and calls in the agency of a miracle” (6). Darwin of course assumed that the ‘now operational’ variations observed in animal breeding could likewise explain macro-evolutionary changes throughout the history of life.
An alternative approach to the causal adequacy question is to seek out additional lines of evidence that either prop up or debunk competing explanations. Stephen Meyer expounds on this salient point in the seventh chapter of his most recent book Signature In The Cell,
“the process of determining the best explanation often involves generating a list of possible hypotheses, comparing their known (or theoretically plausible) causal powers against the relevant evidence, looking for additional facts if necessary, and then, like a detective, progressively eliminating potential but inadequate explanations until, finally, one causally adequate explanation for the ensemble of relevant evidence remains” (p.166)
Historical scientists are of course not the only group to employ such a procedural chain. Meyer’s impressive list of distinguished professions- including clinical diagnosticians and forensic detectives- that are ’cause-focused’ in their modes of operation, gives us much to ponder over. And his follow-on question is brilliantly relevant- might not intelligent design supply the most causally adequate explanation for the origin of biological information? The answer may surprise some. It turns out that by the same ‘vera causa’ line of reasoning used by Darwin 150 years ago, intelligent causation in biology remains a distinct possibility. After all, a cornerstone claim in the ID offensive is that we routinely observe intelligent agents as ’causes now in operation’ that generate the same type of specified information as we find in DNA.
Meyer goes on to boldly entertain the idea that intelligent design presents us with the only causally adequate explanation for the origin of biological information and spends much of the remainder of his book tying together substantial evidence in support of his position. As for Darwin, one can only imagine how he might have felt coming back to find intelligent design legitimized through his very own criterion. My hunch is that he would have applauded the current state of debate.
1. For a summary of Whewell’s work, see biologist Robert J O’Hara’s discussion at http://rjohara.net/darwin/palaetiology
2. Phillip R. Sloan (2006), Kant On The History Of Nature: The ambiguous heritage of the critical philosophy for natural history, Stud. Hist. Phil. Biol. & Biomed. Sci. 37 (2006), pp.627â€“648
3. Peter Lipton: Philosopher of science renowned for his account of inference and explanation, Obituary appeared in The Guardian, Thursday 13th December, 2007, See http://www.guardian.co.uk/news/2007/dec/13/guardianobituaries.obituaries1
4. For a detailed account of Thomas Chamberlin’s work, see http://geology.about.com/od/history_of_geology/a/aa_geothinking.htm
5. See Absolute Astronomy, http://www.absoluteastronomy.com/topics/Abductive_reasoning
6. Charles Darwin (1859), The Origin of Species By Means of Natural Selection Or The Preservation of Favored Races In the Struggle For Survival, Modern Library Paperbacks Edition (1998), New York, p.488