Illustrations of the Huttonian Theory of the Earth

by John Playfair

Note xxiii. § 128.

Geology of Kirwan and De Luc.

419. The two champions of the Neptunian system, who have distinguished themselves most by their hostility to Dr Hutton, are De Luc and Kirwan. They have carried on their attack nearly on the same plan, and have employed against their antagonist the weapons both of theology and science. With a spirit as injurious to the dignity of religion, as to the freedom of philosophical inquiry, they have disregarded a maxim enforced by the authority of Bacon, and by all our experience of the past; "Tanto magis hæc vanitas inhibenda venit et coërcenda, quia, ex divinorum et humanorum male-sana admixtione, non solum educitur philosophia phantastica, sed etiam religio hæretica. Itaque salutare admodum est, si mente sobriâ, fidei tantum dentur quæ fidei sunt."[228]

[228] The whole passage is deserving of attention, and it seems as if the prophetic spirit of Bacon had addressed it to the cosmologists of the present day. "Pessima enim res errorem apotheosis, et pro peste intellectús habenda est, si vanis accedat veneratio. Huic autan vanitati nonnulli ex modernis summâ levitate ita indulserunt, ut, in primo capitolo Geneseos, et aliis Scripturis Sacris, philosophiam naturalem fundari conati sunt: Inter viva quærentes mortua.—"Nov. Organum, lib. i. aphor. 65

Proceeding, accordingly, in direct opposition to rules that, have never yet been violated with impunity, and mistaking the true object of a theory of the earth, they carry back their inquiries to a period prior to the present series of causes and effects, where, having neither experience nor analogy to direct them, they pretend to be guided by a superior light. They would have us to consider their geological speculations as a commentary on the text of Moses; they endeavour to explain the action of creative power, and, with indiscreet curiosity, would tear off the veil which the hand of the prophet has so wisely respected. But the veil cannot be torn off, and all that is behind it must be to man as that which never has existed.

420. M. De Luc has nevertheless treated very diffusely of the history of the solar system, previous to the establishment of the present laws of nature, and has dwelt on it with great complacency, and singular minuteness of detail. His tenth letter to La Metherie has the following title:

"On the History of the Earth, from the time when that planet was penetrated by light, till the appearance of the sun; a portion of time which includes the origin of heat, and of the figure of the earth; of its primeval strata, of the ancient sea, of our continents, as the bottom of that sea, of the great chains of mountains, and of vegetation."[229]

[229] Journal de Physique, tom. 37. (1790,) partie 2de, p. 332. As I may not have done justice to this extraordinary title, it may be right to present it in the original. "Sur l'Histoire de la Terre, depuis que cette planette fut penetrée de lumiere, jusqu'à l'apparition du soleil; espace de tems qui renferme les origines de la chaleur, et de la figure de notre globe; de ses couches primordiales, de l'ancienne mer, de nos continens, comme fond de cette mer, de leurs grandes chaînes de montagnes, et de la vegetation."

I must confess that I am unacquainted with every thing of this letter but the title; and could not easily be prevailed on to follow any man who professedly goes out of nature in search of knowledge; who pretends to give the history of our planetary system when there was no sun, and to enumerate the events which took place between the existence of that luminary, and the existence of light. 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.

421. It sets, however, in a strong light, the inconsistencies that may be observed in the intellectual character of the same individual, to consider that the author of this strange and inconsistent reverie, is, nevertheless, an excellent observer, and well skilled in experimental inquiries. It will hardly be believed that he who writes the history of the earth before the formation of the sun, is versed in the principles of inductive reasoning; and that he has added much to the stock of geological knowledge, having observed accurately, and described with great perspicuity and candour. His Lettres Physiques are full of valuable and just observations, though accompanied with reasonings that do not seem always entitled to the same praise; and in another work he has succeeded where many men of genius had failed, and has made considerable improvements in a branch of the mathematics, without borrowing almost any assistance from the principles of that science.[230]

[230] Essai sur les Modifications de l'Atmosphere.

422. Some of the same observations apply to Mr Kirwan. His Geological Essays have also for their object to explain the first origin of things; and to say that he has not succeeded, in an attempt where no man ever can succeed, implies no reproach on the execution of his work, whatever it may do on the design. We have indeed no criterion by which the execution of it can be estimated: what would in any other place be a blemish, may be here deserving of praise; and if the work is full of confusion and perplexity, these are qualities inherent in the subject which it is intended to describe. It were, no doubt, to be wished, that after emerging into the regions of day, Mr Kirwan had been as successful in copying the beauty and simplicity of nature, as in representing the disorder and inconsistency of the chaotic mass. But his cosmology is without unity in its principles, or consistency in its parts; the causes introduced, are, for the most part, such as will account for one set of appearances just as well as for another; or, if any of them is likely to prove inadequate to the effect ascribed to it, a new and arbitrary hypothesis is always ready to come to its assistance. The information given is seldom exact: a multitude of facts brought together, without the order and discussion essential to precise knowledge; and an infinity of quotations, amassed without criticism or comparison, afford proofs of extensive reading, but of the most hasty and superficial inquiry. Thus we have seen passages from Ulloa and Frisi, produced in support of opinions, which, when fairly stated, they had the most direct tendency to overthrow.

423. In one respect, the geological writings of Kirwan are far inferior to De Luc's: They are evidently the productions of a man who has not seen nature with his own eyes; who has studied mineralogy in cabinets, or in books only; but who has seldom beheld fossils in their native place. With the balance in his hand, and the external characters of Werner in his view, he has examined minerals with diligence, and has discovered many of those marks which serve to ascertain their places, in a system of artificial arrangement. But to reason and to arrange are very different occupations of the mind; and a man may deserve praise as a mineralogist, who is but ill qualified for the researches of geology.

424. The same hurry and impatience are visible in the manner in which his argument against Dr Hutton is usually conducted. He has seldom been careful to make himself master of the opinions of his adversary; and what he gives as such, and directs his reasonings against, have often no resemblance to them whatsoever. Without any intention to deceive others, but deceived himself, he usually begins with misrepresenting Dr Hutton's notions, and then proceeds to the refutation of them. In this imaginary contest, it will readily be supposed, that he is in general successful: when a man has the framing both of his own argument, and that of his antagonist, he must be a very unskilful logician if he does not come off with the advantage.

425. It is but justice, however, to the Neptunists, to acknowledge, that they are not all liable to the censure of beginning their researches from a period antecedent to the existence of the laws of nature. This absurdity does not, so far as I know, infect the system of Werner. That mineralogist has not proposed to explain the first origin of things, though he has supposed, at some former period, a condition of the globe very unlike the present, viz. the entire submersion of the solid under the fluid part.