Part 13 (1/2)

Hutton was in advance of the geological speculation of his time, because, in the first place, he had ama.s.sed a vast store of knowledge of the facts of geology, gathered by personal observation in travels of considerable extent; and because, in the second place, he was thoroughly trained in the physical and chemical science of his day, and thus possessed, as much as any one in his time could possess it, the knowledge which is requisite for the just interpretation of geological phenomena, and the habit of thought which fits a man for scientific inquiry.

It is to this thorough scientific training that I ascribe Hutton's steady and persistent refusal to look to other causes than those now in operation for the explanation of geological phenomena.

The internal heat of the earth, the elevation and depression of its crust, its belchings forth of vapours, ashes, and lava, are its activities, in as strict a sense as are warmth and the movements and products of respiration the activities of an animal. The phenomena of the seasons, of the trade winds, of the Gulf-stream, are as much the results of the reaction between these inner activities and outward forces as are the budding of the leaves in spring and their falling in autumn the effects of the interaction between the organisation of a plant and the solar light and heat. And, as the study of the activities of the living being is called its physiology, so are these phenomena the subject-matter of an a.n.a.logous telluric physiology, to which we sometimes give the name of meteorology, sometimes that of physical geography, sometimes that of geology. Again, the earth has a place in s.p.a.ce and in time, and relations to other bodies in both these respects, which const.i.tute its distribution. This subject is usually left to the astronomer; but a knowledge of its broad outlines seems to me to be an essential const.i.tuent of the stock of geological ideas.

CCXXIV

All that can be ascertained concerning the structure succession of conditions, actions, and position m s.p.a.ce of the earth, is the matter of fact of its natural history. But? as in biology, there remains the matter of reasoning from these facts to their causes, which is just as much science as the other, and indeed more; and this const.i.tutes geological aetiology.

CCXXV

I suppose that it would be very easy to pick holes in the details of Kant's speculations, whether cosmo-logical, or specially telluric, in their application. But for all that, he seems to me to have been the first person to frame a complete system of geological speculation by founding the doctrine of evolution.

I have said that the three schools of geological speculation which I have termed Catastrophism, Uniformitarianism, and Evolutionism, are commonly supposed to be antagonistic to one another; and I presume it will have become obvious that in my belief, the last is destined to swallow up the other two. But it is proper to remark that each of the latter has kept alive the tradition of precious truths.

To my mind there appears to be no sort of necessary theoretical antagonism between Catastrophism and Uniformitarianism. On the contrary, it is very conceivable that catastrophes may be part and parcel of uniformity. Let me ill.u.s.trate my case by a.n.a.logy. The working of a clock is a model of uniform action; good time-keeping means uniformity of action. But the striking of the clock is essentially a catastrophe; the hammer might be made to blow up a barrel of gunpowder, or turn on a deluge of water; and, by proper arrangement, the clock, instead of marking the hours, might strike at all sorts of irregular periods, never twice alike, in the intervals, force, or number of its blows.

Nevertheless, all these irregular, and apparently lawless, catastrophes would be the result of an absolutely uniformitarian action; and we might have two schools of clock-theorists, one studying the hammer and the other the pendulum.

CCXXVI

Mathematics may be compared to a mill of exquisite workmans.h.i.+p, which grinds your stuff of any degree of fineness; but, nevertheless, what you get out depends upon what you put in; and as the grandest mill in tne world will not extract wheat-flour from peascods, so pages of formulae will not get a definite result out of loose data.

CCXXVII

The motive of the drama of human life is the necessity, laid upon every man who comes into the world, of discovering the mean between self-a.s.sertion and self-restraint suited to his character and his circ.u.mstances. And the eternally tragic aspect of the drama lies in this: that the problem set before us is one the elements of which can be but imperfectly known, and of which even an approximately right solution rarely presents itself, until that stern critic, aged experience, has been furnished with ample justification for venting his sarcastic humour upon the irreparable blunders we have already made.

CCXXVIII

That which endures is not one or another a.s.sociation of living forms, but the process of which the cosmos is the product, and of which these are among the transitory expressions. And in the living world, one of the most characteristic features of this cosmic process is the struggle for existence, the compet.i.tion of each with all, the result of which is the selection, that is to say, the survival of those forms which, on the whole, are best adapted to the conditions which at any period obtain; and which are therefore, in that respect, and only in that respect, the fittest. The acme reached by the cosmic process in the vegetation of the downs is seen in the turf, with its weed and gorse. Under the conditions, they have come out of the struggle victorious; and, by surviving, have proved that they are the fittest to survive.

CCXXIX

As a natural process, of the same character as the development of a tree from its seed; or of a fowl from its egg, evolution excludes creation and all other kinds of supernatural intervention. As the expression of a fixed order, every stage of which is the effect of causes operating according to definite rules, the conception of evolution no less excludes that of chance. It is very desirable to remember that evolution is not an explanation of the cosmic process, but merely a generalized statement of the method and results of that process. And, further, that, if there is proof that the cosmic process was set going by any agent, then that agent will be the creator of it and of all its products, although, supernatural intervention may remain strictly excluded from its further course.

CCx.x.x

All plants and animals exhibit the tendency to vary, the causes of which have yet to be ascertained; it is the tendency of the conditions of life, at any given time, while favouring the existence of the variations best adapted to them, to oppose that of the rest and thus to exercise selection; and all living things tend to multiply without limit, while the means of support are limited; the obvious cause of which is the production of offspring more numerous than their progenitors, but with actual expectation of life in the actuarial sense. Without tne first tendency there could be no evolution. Without the second, there would be no good reason why one variation should disappear and another take its place; that is to say, there would be no selection. Without the third, the struggle for existence, the agent of the selective process in the state of nature, would vanish.

CCx.x.xI

The faith which is born of knowledge finds its object in an eternal order, bringing forth ceaseless chance, through endless time, in endless s.p.a.ce; the manifestations of the cosmic energy alternating between phases of potentiality and phases of explication.

CCx.x.xII