ARTICLE II.-A CRITICAL EXAMINATION OF PROFESSOR HUXLEY'S "PHYSICAL BASIS OF LIFE."

A LITTLE less than eighteen months ago a remarkable address was delivered in Edinburgh, by Professor Thomas H. Huxley, of London, which has been published and extensively circulated, and has attracted much attention. Its author is Professor of Comparative Anatomy and Physiology in the Royal College of Surgeons, and has for some years held a prominent position among English physicists. The striking facts and startling assertions of the writer, and especially the bold and almost defiant manner in which they are presented, are well calculated to excite the attention of thinking men. Professor Huxley did not hesitate in this address to avow himself a follower of David Hume, and to quote with approval this sentiment of that philosopher:

"If we take in hand any volume of Divinity or school metaphysics, let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames; for it can contain nothing but sophistry and illusion."

He boldly declared that all inquiries about spiritual things lie "outside of the limits of philosophical enquiry," and cannot be matters of knowledge or faith; and told his hearers that if they accepted his conclusions "they had placed their feet on the first rung of a ladder which, in many people's estimation," and he did not except himself, "leads to the antipodes of heaven." He, to be sure, denies that he is a materialist, and yet affirms that "matter may be regarded as a form of thought, thought may be regarded as a property of matter," and again, "matter and spirit are but names for the imaginary substrata of groups of natural phenomena," leaving his readers in doubt whether to class him among materialists or nihilists.

It is not surprising that such views have been received with satisfaction by those who believe that there is a contest waging between physical science and faith, in which the former is to

gain the victory; and that the offensive manner in which they have been presented has caused them to be regarded by others with suspicion so strong as to prevent their acquainting themselves with either the facts, the arguments, or the conclusions of the essay. We do not sympathize with either of these classes. We do not believe in any necessary antagonism between physical science and religious or Christian faith. We are at times amused, and, it may be, vexed with the arrogance of physicists, as if all knowledge was to die with them, especially when we find one theorist of this sort opposing another; one stoutly affirming what the other denies. Indeed, when we have heard what have been regarded as some of the best established principles of physical science overthrown and again re-established, we have sometimes thought that it was not worth while to interfere in their disputes. But theories and conclusions which are put forth with so much assurance, and in the way of challenge to all the world, and which are accepted by so many as indisputable, ought not to be passed by without notice. We propose, then, to examine the theories and arguments of this essay. If it shall be found on examination that the facts do not sustain the theories, it will not be the first time in history that on "the battle fields of science" the performance has not equalled the promise.

The first thing which strikes us in reading the essay is the loose estimate which the writer puts on language as a means of expressing ideas. He tells us, indeed, "that scientific language should possess a definite and constant signification," yet when it suits one purpose, he says that "matter and life are inseparably connected," and with another object in view he speaks of "lifeless matter." He denies that in nature there is anything which corresponds to the metaphysical idea of "cause and effect," and notwithstanding this he uses these terms in his essay and makes much of the "powers of matter," and reasons about the "direct results of the nature of matter," as if there could be a power which produces no effect, and a result which is traceable to no cause. In the conclusion of his essay he uses this language, "If we find that the ascertainment of the order of nature is facilitated by using one terminology or one set of symbols, rather than another,

it is our clear duty to use the former, and no harm can accrue so long as we bear in mind that we are dealing with terms and symbols. In itself it is of little moment whether we express the phenomena of matter in terms of spirit or the phenomena of spirit in terms of matter." A remarkable declaration, certainly, to come from an eminent professor of physical science, the superior adaptation of which to train the mind to habits of precision is the continual boast of its friends. We shall have occasion, as we proceed, to notice the singular use of words by our author, and shall, perhaps, find that he has been led into some striking fallacies by it. We allude to it now that our readers may have it in mind as the examination of the argument.

we advance in

Professor Huxley announces his subject as "Protoplasm," but as he supposes this term is not generally intelligible he translates it, for the benefit of the unscientific, into the phrase

Physical Basis of Life." We regard it as unfortunate that a term which has acquired a definite signification, should have been exchanged for such a phrase as "Physical Basis of Life," or that the writer had not at least explained what he means by this somewhat ambiguous expression. For instance, he nowhere tells us what he means by "life." He, indeed, states the common conception of life to be "something which works through matter, but is independent of it," leading us to suppose that he himself conceives of "life" as something different from this; but whether, in his view, life is something which does not work through matter, meaning something which has no connection with matter, or as something which is dependent on matter, we are not clearly informed. In the next line of his printed essay we find it stated that "life and matter are inseparably connected," which seems to be intelligible, and we understand him to hold that the stones have life, and even the "cooked mutton," about which he is so learned and witty, declaring that it is "competent to resume its old functions as matter of life," although now "dead."

He afterwards, however, speaks of "lifeless matter," that is matter which is not "inseparably connected with life," under which class he includes cooked mutton, but as he does not explain how the cooked mutton can be "lifeless" and yet have

power to do what he says it is competent to do, we are left in doubt as to his making any real distinction between the living and the lifeless. He seems here to think it of no importance what terminology he uses. So, too, "basis" is a word having a definite meaning as a foundation on which a superstructure. of life for instance, is or may be built, and we should suppose that to be its meaning here, but that we find Professor Huxley almost immediately using it as synonymous with "matter," as if he intended by it the material substance out of which life is made, and we finally conclude this latter to be his real meaning. If, however, Professor Huxley does not explain the expression, "Physical Basis of Life," he goes on to inform us what conclusion is suggested by it, viz: "that there is one kind of matter which is common to all living beings, and that their endless diversities are bound together by a physical unity." This statement is simple and definite, and we think we have arrived at the truth which this teacher is about to present to us, and we inquire is this the new philosophy which is to revolutionize the opinions of men? Is this the conclusion "shocking to common sense," by accepting which we are to be led away from heaven? Is this the foundation for the somewhat glowing rhetoric with which Professor Huxley brings into one class the brightly colored lichen of the rock and the painter who strives to reproduce it on the canvass; the microscopic fungus and the gigantic Californian pine; the flower which adorns a girl's hair and the blood which courses through her veins ?

It is no new idea that there is one kind of matter common to all living beings and inanimate things as well. Chemistry long ago told us that all material substances may be resolved into a few simple elements. The experience of the world has shown from the first, that at death all living things are changed into their inanimate constituents. The oldest book we have teaches among its earliest utterances that man, the head of creation, was formed of the dust of the ground. We have no difficulty with this "conclusion" which the Professor announces. We accept it heartily. There is a sense in which all animals are "bound together in a physical unity," and in that sense we assent to the proposition; not meaning thereby that all

living things are parts of one vast material substance, or that they have all sprung from the same grain of matter; not asserting that there is no diversity; but such a unity as is indicated by the word of God, and by the experience of men coupled with the investigations of science.

Professor Huxley does not allow us to rest long on this proposition. He proceeds to develop his theory more in detail.

Before proceeding, however, to discuss his arguments, we will quote from his essay some passages which will serve to acquaint our readers with the facts on which these arguments

rest:

"You are doubtless aware that the common nettle owes its stinging property to the innumerable stiff and needle-like, though exquisitely delicate, hairs which cover its surface. Each stinging-needle tapers from a broad base to a slender summit, which, though rounded at the end, is of such microscopic fineness that it readily penetrates, and breaks off in the skin. The whole hair consists of a very delicate outer case of wood, closely applied to the inner surface of which is a layer of semi fluid matter, full of innumerable granules of extreme minuteness. This semi-fluid lining is protoplasm, which thus constitutes a kind of bag, full of a limpid liquid, and roughly corresponding in form with the interior of the hair which it fills. When viewed with a sufficiently high magnifying power, the protoplasmic layer of the nettle hair is seen to be in a condition of unceasing activity. Local contractions of the whole thickness of its substance pass slowly and gradually from point to point, and give rise to the appearance of progressive waves, just as the bending of successive stalks of corn by a breeze produces the apparent billows of a corn-field. But, in addition to these movements, and independently of them, the granules are driven, in relatively rapid streams, through channels in the protoplasm which seem to have a considerable amount of persistence. Most commonly, the currents in adjacent parts of the protoplasm take similar directions; and thus, there is a general stream up one side of the hair and down the other. But this does not prevent the existence of partial currents which take different routes; and, sometimes, trains of granules may be seen coursing swiftly in opposite directions, within a twenty-thousandth of an inch of one another; while, occasionally, opposite streams come into direct collision, and after a longer or shorter struggle one predominates. The cause of these currents seems to lie in contractions of the protoplasm which bounds the channels in which they flow, but which are so minute that the best microscopes show only their effects, and not themselves."

"If a drop of blood be drawn by pricking one's finger, and viewed with prop er precautions and under a sufficiently high microscopic power, there will be seen among the innumerable multitude of little, circular, discoidal bodies or corpuscles, which float in it and give it its color, a comparatively small number of colorless corpuscles, of somewhat larger size and very irregular shape. If the drop of blood be kept at the temperature of the body, these colorless corpuscles will be seen to exhibit a marvelous activity, changing their forms with great ra15

VOL. XXIX.