Gould, Justice Scalia's Misunderstanding

we can state about science as a way of knowing. Our failure to grasp the principle underlies much public misperception about science. In particular, Justice Scalia's recent dissent in the Louisiana "creation science" case rests upon this error when it discusses the character of evolutionary arguments. We all rejoiced when the Supreme Court ended a long episode in American history and voided the last law that would have forced teachers to "balance" instruction in evolution with fundamentalist biblical literalism masquerading under the oxymoron creation science. I now add a tiny hurrah in postscript by pointing out that the dissenting argument rests, in large part, upon a misunderstanding of science.

Hutton replied to Kirwan's original attack by expanding his 1788 treatise into a cumbersome work, The Theory of the Earth (1795). With its forty-page quotations in French and its repetitive, involuted justifications, Hutton's new work condemned his theory to unreadability. Fortunately, his friend John Playfair, a mathematician and outstanding prose stylist, composed the most elegant pony ever written and published his Illustrations of the Huttonian Theory of the Earth in 1802. Playfair presents a two-part refutation for Kirwan's charge of atheism.
Hutton neither argued that the earth was eternal nor even claimed that we could say nothing about its origin. In his greatest contribution, Hutton tried to develop a cyclical theory for the history of the earth's surface, a notion to match the Newtonian vision of continuous planetary revolution about the sun. The materials of the earth's surface, he argued, passed through a cycle of perfect repetition in the large. Consider the three major stages. First, mountains erode and their products are accumulated as thick sequences of layered sediments in the ocean. Second, sediments consolidate and their weight melts the lower layers, forming magmas. Third, the pressure of these magmas forces the sediments up to form new mountains (with solidified magmas at their core), while the old, eroded continents become new ocean basins. The cycle then starts again as mountains (at the site of old oceans) shed their sediments into ocean basins (at the site of old continents). Land and sea change positions in an endless dance, but the earth itself remains fundamentally the same. Playfair writes:
It is the peculiar excellence of this theory ... that it makes the decay of one part subservient to the restoration of another, and gives stability to the whole, not by perpetuating individuals, but by reproducing them in succession.

We can easily grasp the revolutionary nature of this theory for concepts of time. Most previous geologies had envisioned an earth of short duration, moving in a single irreversible direction, as its original mountains eroded into the sea. By supplying a "concept of repair" in his view of magmas as uplifting forces, Hutton burst the strictures of time. No more did continents erode once into oblivion; they could form anew from the products of their own decay and the earth could cycle on and on.

This cyclical theory has engendered the false view that Hutton considered the earth eternal. True, the mechanics of the cycle provide no insight into beginnings or ends, for laws of the cycle can only produce a continuous repetition and therefore contain no notion of birth, death, or even of aging. But this conclusion only specifies that laws of the present order of nature cannot specify beginnings or ends. Beginnings and ends may exist--in fact, Hutton considered a concept of starts and stops absolutely essential for any rational understanding--but we cannot learn anything about this vital subject from natures present laws. Hutton, who was a devoted theist despite Kirwan's charge, argued that God had made a beginning, and would ordain an end, by summoning forces outside the current order of nature. For the stable period between, he had ordained laws that impart no directionality and therefore permit no insight into these beginnings and ends.

Note how carefully Hutton chose the words of his celebrated motto. "No vestige of a beginning" because the earth has been through so many cycles since then that all traces of its original state have vanished. But an original state it certainly had. "No prospect of an end" because the current laws of nature provide no insight into a termination that must surely occur. Playfair describes Hutton's view of God:
He may put an end, as he no doubt gave a beginning, to the present system, at some determinate period; but we may safely conclude, that this great catastrophe will not be brought about by any of the laws now existing, and that it is not indicated by any thing which we perceive.

2. Hutton did not view our inability to specify beginnings and ends as a baleful limitation of science but as a powerful affirmation of proper scientific methodology. Let theory deal with ultimate origins, and let science be the art of the empirically soluble.

The British tradition of speculative geology--from Burnet, Whiston, and Wood-ward in the late seventeenth century to Kirwan himself at the tail end of the eighteenth--had focused upon reconstructions of the earth's origin, primarily to justify the Mosaic narrative as scientifically plausible. Hutton argued that such attempts could not qualify as proper science, for they could only produce speculations about a distant past devoid of evidence to test any assertion (no vestige of a beginning). The subject of origins may be vital and fascinating, far more compelling than the humdrum of quotidian forces that drive the present cycle of uplift, erosion, deposition, and consolidation. But science is not speculation about unattainable ultimates; it is a way of knowing based upon laws now in operation and results subject to observation and inference. We acknowledge limits in order to proceed with power and confidence.

Hutton therefore attacked the old tradition of speculation about the earth's origin as an exercise in futile improvability. Better to focus upon what we can know and test, leaving aside what the methods of science cannot touch, however fascinating the subject. Playfair stresses this theme more forcefully (and more often) than any other in his exposition of Hutton's theory. He regards Hutton's treatise as, above all, an elegant statement of proper scientific methodology--and he locates Hutton's wisdom primarily in his friend's decision to eschew the subject of ultimate origins and to focus on the earth's present operation. Playfair begins by criticizing the old manner of theorizing:
The sole object of such theories has hitherto been, to explain the manner in which the present laws of the mineral kingdom were first established, or began to exist, without treating of the manner in which they now proceed.

He then evaluates this puerile strategy in one of his best prose flourishes:
The absurdity of such an undertaking admits of no apology, and the smile which it might excite, if addressed merely to the fancy, gives place to indignation when it assumes the air of philosophic investigation.

Hutton, on the other hand, established the basis of a proper geological science by avoiding subjects "altogether beyond the limits of philosophical investigation." Hutton's explorations "never extended to the first origin of substances, but were confined entirely to their changes." Playfair elaborated:
He has indeed no where treated of the first origin of any of the earths, or of any substance whatsoever, but only of the transformations which bodies have undergone since the present laws of nature were established. He considered this last as all that a science,