Wednesday, December 19, 2012
Roger White on Origin of Life Explanations 2
Roger White distinguishes three types of phenomena, illustrated by “pebble patterns.”
The Chancy Explanation: Pebbles scattered randomly on a sidewalk require no other explanation than chance.
Unintentional Biasing: Pebbles arranged in order of diminishing size as they a near the shoreline.
Intentional Biasing: Pebbles arranged in the shape of a fish (without legs).
I altered the last one in a way that I hope will be amusing. According to White, all but a few of those who write with expertise on the problem of the origin of life believe this phenomenon must fall into the second category. Some natural forces must bias the Kosmos toward the emergence of life, just as the tides bias the pebbles toward a coherent pattern.
The third explanation is ruled out as unscientific. The first is ruled out because it is wildly implausible that the conditions upon which the emergence of self-replicators depends should have come about, in the time allotted, merely by chance. Unintentional biasing must therefore be true by default.
White argues that the reason that the origin of life is not at all like the unintentional biasing of pebbles by size on the beach.
The numerous steps required for life to exist are quite unlike this. It is not a matter of the same event-type or property being instantiated many times without exception. The conditions required for the emergence of life have little at all in common.
Adding a bit to what White says, the emergence of life on earth seems to have been a single event (however long it took), not a repeated pattern.
Why then are most scientists so reluctant to allow too much chance into their accounts of life’s emergence? I will offer a speculative diagnosis. The conviction that life couldn’t have arisen by chance is typically a gut reaction to the data, not a conclusion arrived at on the basis of a theory about when it is plausible to ascribe something to the work of chance.
What makes this event seem so implausible to so many is that it seems to suggest unmistakable evidence of design.
Again adding to White, I would contrast the origin of life problem with the problem that Darwin addressed. Why do so many different organisms exist, all of them more or less well adapted to their respective ecological niches? That is a pattern that is persistent historically and geographically. Natural selection then can be seen as the unintentional biasing mechanism analogous to the motion of water acting on the pebbles.
Interestingly, unintentional biasing would be a much more likely explanation for the origin of self-replicators if Aristotle had been right about spontaneous generation. If the emergence of living organisms from non-living matter under predictable conditions were a persistent feature of nature, as Aristotle, for understandable reasons, believed that it was, then unintentional biasing toward the emergence of life would be very likely indeed. Of course, this is not the case.
White makes a strong case that unintentional biasing in nature is not a well-grounded explanation for the origin of life. That leaves chance and intentional (or intelligent) design. I would suggest, however, that his dismissal of the gut reactions of so many scientists is premature. To use one of his analogies, if a tornado picked up a pile of spare parts and assembled it into a working 747 airliner, no one would interpret this was the work of mere chance. If even the simplest molecular self-replicators as well-designed as the airplane (which may be the case) and unintentional biasing is not a plausible interpretation of the former, then…
I am not making an argument for intelligent design here. I am not particularly interested in it only because I don’t know what to do with it when thinking philosophically and scientifically about the phenomenon of life. I do think that White’s argument could be turned almost as easily (perhaps just as easily) into an argument for intelligent design as for the origin of life by chance. That fact may tell us something about the phenomenon. If so, it would be unscientific to ignore it.