a.s.suming the process of evolution to be a fact, we have inquired what is the value of that fact, what significance it has for man as a moral being, anxious to direct his life in accordance with the best lights he can obtain. In our attempts to draw any inference from the facts of evolution as to the moral government of the universe, we have always found ourselves ultimately confronted by the notice--The Real is Unknowable. Obviously, if "the ultimate of ultimates," the Real Power or Force, of which all things and beings are manifestations, is unknowable, we cannot know whether it cares or does not care for what is true or good. But if the Real is Unknowable, then the knowledge which we do possess is not knowledge of the real, and consequently all our science is unreal knowledge; the theory of evolution is a system of delusive inferences from unreal facts. That, however, is a thing which we could not believe. Doubtless our knowledge is small compared with our ignorance. Doubtless there is much which the human mind could not understand without becoming more than human. Doubtless, also, every addition to our knowledge involves a readjustment and correction of our previous inferences; and a considerable addition, such as the theory of evolution was, causes a considerable change in our conception of the universe and its laws. But all these admissions cannot compel us to admit that science is wholly unreal knowledge, or that evolution is an entirely unreal process. We sought, accordingly, to show that we have some, if only partial, knowledge of the real, that that knowledge is not wholly inferential, but that so far as it is inferred it is inferred from real facts, the reality of which is directly apprehended in the common experience of mankind.

As a matter of fact, those writers who proclaim the unknowability of the Real, when they are writing as philosophers, abandon it when they are engaged in science. When they are working out the theory of evolution, they take it for granted that the process of evolution is a reality, that the common experience of mankind is trustworthy to some extent, and that to that extent the Real is knowable and known. They a.s.sure us that, though the knowledge we have is not knowledge of the Real, it is just the same for us as if it were--if the Real could enter into our consciousness, we really should not know the difference. "Thus then we may resume, with entire confidence, those realistic conceptions which philosophy at first sight seems to dissipate."[8]

On examination, however, it turns out that the entire confidence which is thus restored to the reality of material things is not extended to the reality of those ideals of the good, the beautiful, and the holy which play their part in the lives of men and in the evolution of mankind--or not to all of those ideals.

Now, it is scarcely to be hoped that a theory which begins by ignoring certain facts in the common experience of mankind, or by denying their reality, can end in a satisfactory explanation of them. Either it will be consistent and proclaim them to be illusions, or it will be inconsistent and quietly include them from time to time as it goes on--in which case the explanation it gives of them will be no explanation. Thus, for instance, as we have already argued, the Optimistic interpretation of evolution, professing to exhibit the Ideal of morality as one of the ultimate consequences of the redistribution of matter and motion, ends by denying any difference between what is and what ought to be, and thus reduces the moral ideal to a mere illusion.

The Pessimist, on the other hand, insisting on the reality, and to some extent the supremacy of the moral ideal, confesses his inability to explain its validity as being due to evolution: the fact that it has been evolved does not account for its validity, because the tendency to evil has been also evolved, but is not, therefore, to be yielded to.

The object of this chapter is to examine the hypothesis that the process of evolution is nothing but a perpetual redistribution of matter and motion, and to show that the hypothesis cannot explain, and as a matter of fact does not explain, all the facts which it is framed to account for.

The theory of evolution is an attempt--one of many attempts that men have made--to explain the process by which the totality of things has come to be what it is. It differs from most other attempts in that it endeavours to give a scientific explanation of the process, and that consequently it does not profess to go back to the beginning or to discover the origin of the process.

The nature of scientific "explanation" is well understood by men of science (in England, at least), and has been made familiar to the non-scientific world by John Stuart Mill. An event is scientifically "explained" when it is shown to be a case of a general law; a law is "explained" when it is shown to come under some more general law. In other words, the business of science is to show that the thing under examination always happens (or tends to happen) under certain circ.u.mstances which science can formulate with more or less exactness.

But _how_ or _why_ the thing should happen thus, science does not undertake to explain: "what is called explaining one law of nature by another, is but subst.i.tuting one mystery for another; and does nothing to render the general course of nature other than mysterious: we can no more a.s.sign a _why_ for the more extensive laws than for the partial ones."[9] It is only "minds not habituated to accurate thinking" which imagine that the laws are the _causes_ of the events which happen in accordance with them, "that the law of general gravitation, for example, causes the fall of bodies to the earth."[10] It may be a law of science, a perfectly true statement, that the phenomenon B always follows the phenomenon A; but that statement, true as it is, is not the cause of B.

_That_ A is always followed by B is demonstrated by science. _Why_ it should be followed by B is as mysterious as magic--as mysterious as that the waving of the magician's wand should be immediately followed by the rising of a palace from the ground. How the one thing _can_ follow the other, is no part of science's business to explain.

Science, therefore, is essentially descriptive: with ever-increasing accuracy it describes things and the order in which they happen.

Evolution, then, as a scientific theory, is also purely descriptive: it describes the way in which things have come to be what we see them to be, the process by which the totality of things has come to be what it is. But when the purely scientific and descriptive part of the work is done, when science has formulated the order of the events which have led up to the existing state of the universe, when the process of evolution has been described, there still remain the questions which science refused even to try to answer, and there also remain other questions more vital to science. There arises the question, In what sense is evolution a real process? do the laws of science exist only in the minds of men of science? is the process of evolution merely the description which is given of it (as according to some thinkers a thing is only the sensations which we have of it), or is it something more?

Obviously the question whether evolution is a real process, whether there is any reality in science, is one which cannot be answered, either in the affirmative or in the negative, without some idea of what "reality" means, of what the "real" is. "What is the meaning of the word _real_? This is the question which underlies every metaphysical inquiry; and the neglect of it is the remaining cause of the chronic antagonisms of metaphysicians."[11] Before we are logically ent.i.tled to say that evolution is a real process, we must answer the question, "What is the essence, the ultimate reality of things? who or what is the Being that is manifested in 'all thinking things, all objects of all thought'?"[12]

Now, to these questions, as to the Being and Becoming of the universe, science has nothing to say. Science does not even afford the materials for an answer to them, any more than to those other questions as to _how_ or _why_ things should happen in the way which science describes.

Science describes things, but does not undertake to prove that things exist. Science is organised common sense, and common sense takes it for granted that things exist. Having made this a.s.sumption, science proceeds to investigate with scientific exactness the order in which events succeed one another and co-exist with one another, within the range of direct observation; and infers that, even when they are beyond the range of direct observation, they continue to occur in the same order of sequence and co-existence. But here again science refuses to have anything to do with any metaphysical questions as to _how_ or _why_ things should thus occur. All sorts of conjectures may be made, and have been made, to explain why B should follow A, or co-exist with it. But science is not pledged to any of them. The only thing she undertakes to show is the fact of the sequence or co-existence; and this she can do without a.s.suming the truth of any of these conjectures. Indeed, the progress which science has made is largely due to the fact that she has steadily declined to have anything to do with such conjectures--having found out by experience that they simply distract her from her proper business of observing with the utmost exactness what actually does take place. It may be that A in some mysterious and wholly inexplicable way "produces" B, that is to say in technical phraseology, is "the efficient cause" or "mechanical cause" of B. It may be that the sequence of B upon A is a volition of the Being which is manifested in all thinking things, in all objects of all thought. Science cannot prove, and will not even discuss, either suggestion: she confines herself to the a.s.sertion that, as a matter of careful and exact observation, B does follow A. Whether we call A an efficient cause or not, matters not to science: call it so or refuse to call it so, the fact once established by science, that B follows A, remains. The theory of efficient or mechanical causes is doubtless of importance, but not to science. If it is proved to be false, not a single fact of science is shaken.

The mechanical theory may be true or may be false, but in either case it is a metaphysical theory. If science is descriptive--descriptive of the uniform succession and co-existence of facts--then science no more proves the mechanical theory to be true than it proves the volitional theory to be true. Both are theories as to _why_ facts should succeed one another in the order described by science; and science does not undertake to prove the truth of such theories, nor does she wait for them to be proved or disproved.

Many men of science, however, are also philosophers, and hold, as they are fully ent.i.tled to hold, that the mechanical theory is the true interpretation of nature. Now, "mechanics is the science of motion; we can a.s.sign as its object: to describe completely and in the simplest manner the movements which occur in nature."[13] On the mechanical theory, therefore, "the object of all science is to reduce the phenomena of nature to forms of motion, and to describe these completely and in the simplest manner ... the only complete description is that afforded by a mathematical formula, in which the constants are supplied by observation. This permits us to calculate those features or phases of phenomena which are hidden from our observation in s.p.a.ce or in time."[14] This, we need hardly add, is in agreement with Mr. Herbert Spencer's view of the theory of evolution as a description of the process of the redistribution of matter and motion.

It seems, then, that according to this particular metaphysical theory, which maintains the mechanical explanation of nature to be the true one, the object of all science is to describe (with mathematical accuracy, where possible) the movements of things in s.p.a.ce. But science is universal; evolution extends to the whole cosmic process. Therefore, the only things with which science has to do, or which are factors in the cosmic process, are things moving in s.p.a.ce.

As a metaphysical argument this theory seems to us unsatisfactory. It converts, simply and illegitimately, the proposition sanctioned by common sense, that material things are real, into the proposition opposed to common sense, that all real things are material. It a.s.sumes, apparently unconsciously and certainly without proof, that the only things capable of scientific description are movements in s.p.a.ce, the only laws in the universe mechanical laws.

Historically, material things were the first to be studied and described with scientific exactness. It is only natural, therefore, that the methods and a.s.sumptions which have been employed with conspicuous success by the physical sciences should be extended, tentatively at least, elsewhere. It is equally natural that protests should be raised, and the extension proclaimed by philosophers to be illegitimate--"impoverishing faith without enriching knowledge."[15]

"To regard the course of the world as the development of some blind force which works on according to universal laws, devoid of insight and freedom, devoid of interest in good and evil, are we to consider this unjustifiable generalisation of a concept, valid in its own sphere, as the higher truth?"[16]

It is not, however, likely that science will drop a generalisation, however "unjustifiable" in metaphysics, if it works in practice. The question is whether it does work; and that is plainly a question of fact, not a question of metaphysics. We want to know therefore, first, whether things moving in s.p.a.ce are the only things with which we are acquainted in common experience; and, next, whether all the changes which take place within the range of scientific observation are or can be explained by the laws of mechanics.

It is clear that, if the mechanical theory of science and of evolution is to be successfully maintained, both these questions must be answered in the affirmative. It is equally clear that, if we confine ourselves to the actual facts, both questions must be answered in the negative.

Thoughts, ideas, conceptions, sensations, feelings, emotions are things of which we have experience at every moment of our waking lives; and none of them are things which occupy s.p.a.ce or move in s.p.a.ce. A thought is not a thing which can be measured by a foot-rule, as things in s.p.a.ce can be; the greatness of an idea is not one which measures so many yards by so many; a conception has no cubic contents; a toothache cannot be put in a pair of scales, nor can any process of chemical a.n.a.lysis be applied to hope or fear. We find ourselves, therefore, in this dilemma: if the mechanical theory is true, and science can deal only with things moving in s.p.a.ce, then psychology and sociology are not sciences, and their subject-matter never can be made amenable to scientific treatment.

On the other hand, if psychology is a science, then science deals with things which do not move in s.p.a.ce.

We submit that psychology _is_ a science, that our sensations, emotions, ideas, etc., can be observed, and can be described scientifically, that is to say, that their uniform sequences and co-existences can be stated with accuracy and formulated as laws. We submit further that our definition of science should be based on facts, and not framed to suit a metaphysical theory. A satisfactory definition of science must include all the sciences. The definition put forward in the interests of the mechanical theory excludes arbitrarily the mental and moral sciences, and implies that their subject-matter is beyond the power of science to deal with. The exclusion and the implication are consequent upon the suggested limitation of science to things moving in s.p.a.ce, and are of the essence of the mechanical theory. Both the exclusion and the implication are unnecessary if we adhere to the older conception of science, as it occurs in Mill, which claims for science all phenomena of which the sequences and co-existences can be observed, described, and formulated as laws.

What we have said with regard to science applies also of necessity to Evolution. If Evolution is simply the continual redistribution of matter and motion, if matter and motion are the only things subject to evolution, then consciousness and conscience are not subject to evolution. On the other hand, if they too have had and are having their evolution, then the redistribution of matter and motion does not sum up the process of evolution, and is not a correct statement of the process.

If it were an induction drawn from a consideration of all the facts of evolution, it would cover them all. But it does not: it excludes a large cla.s.s of important facts, because their exclusion is demanded in the interests of a particular metaphysical theory--the mechanical theory. It implies that the operation of evolution is confined to a limited set of facts. If the implication is false, then evolution is a bigger thing than the mere redistribution of matter and motion.

The way in which it is usually attempted to force the mechanical theory to square with the facts, or rather to cut the facts to fit the theory, is to point to the connection between the mind and the brain, and to proclaim the consequent dependence of mind on matter. Now, that there is a connection between mind and brain is certain. What the connection is exactly is as yet uncertain. But the fact that two things co-exist, are connected with one another and vary together, does not prove that the one thing is the other. On the contrary, it postulates that the two things, though related, are different. The mechanical theory either commits the fallacy of mistaking connected things for identical things, or it fails to prove the very thing necessary for its justification, viz. that thoughts, emotions, etc., are things occupying s.p.a.ce and moving in s.p.a.ce. The chemical and physiological changes which take place in the brain are movements in s.p.a.ce. But it does not follow that the corresponding pains or ideas float about in the air or move from one point in s.p.a.ce to another.

Further, as a metaphysical theory, this identification of matter with mind is a double-edged weapon: it cuts both ways: if mind is matter, matter is mind; if mind is thinking matter, then matter is latent thought; and thought is consequently exhibited not as being the last product of evolution, but as a factor in it from the beginning. But this ident.i.ty of mind and matter is a purely metaphysical speculation: it is a conjecture to explain _how_ it is that two phenomena can co-exist in the way in which they are observed to do. Such conjectures science does not require: she does not undertake to explain why things are, but to describe--if possible with mathematical exactness--the order of their sequence or co-existence. This function science can discharge equally well whether the changes of consciousness are or are not supposed to be movements in s.p.a.ce. Metaphysicians may argue the point; in the meantime science is describing and formulating the laws of mind and endeavouring to correlate the changes of consciousness with the physical changes of the brain and the nervous system. The mechanical theory neither helps nor hinders science in her work.

But science does throw some difficulties in the way of the mechanical theory; or, rather, the facts of science refuse to fit into the theory.

If the stream of consciousness is nothing but a series of physiological and chemical changes, the laws of the one ought to be identical with the laws of the other, and both with the laws of mechanics, on the mechanical theory. But they are not. Those concise descriptions of mental phenomena which const.i.tute the laws of psychology ought to coincide with those other concise descriptions of fact which const.i.tute the laws of chemistry, if the facts described by the two sciences are the same. But the two sets of laws have, to say the least, more differences than resemblances.

This brings us to our second point. Our first point was that if the concise description of evolution, which sums it up as the process by which matter is continually redistributed in s.p.a.ce, is to be proved to be true, it must be shown that movements in s.p.a.ce are the only events which we know to take place. Our second point is that, unless it can be shown that mechanical laws are the only laws at work in the universe, this description of evolution does not find room for the whole working of the process of evolution.

Whether the only laws in the universe are mechanical laws is primarily a question of fact; and on the facts, as known to us at present, the answer to the question is a decided negative. The laws of psychology and of ethics are neither identical with nor have they been deduced from any physical laws. As a hypothesis designed to explain the way in which the world works, the redistribution of matter and motion neither includes nor accounts for those laws which are of most importance to man.

This appeal to the facts which are actually known is, however, often conceived to be in reality an appeal to our ignorance: mental laws have not as yet been shown to be deducible from physical laws, but they may be. So, too, the fact that no attempt to extend the gravitation formula from astronomy to any other department of science has yet succeeded, is no proof that it never will be so extended. Neither, we may remark, does it const.i.tute any presumption that it will. Are there, then, any other grounds for presuming that mental law may yet be shown to be merely a case of some physical law? To some minds there seem to be grounds for presuming that it not only may, but must. However great our ignorance of the details of the process of evolution, there are certain broad facts which are beyond dispute. It is indisputable that there was a period in the history of the earth when there was no life upon it; that the elements which const.i.tute living matter are themselves lifeless; that consciousness is correlated somehow with those organic compounds, the elements of which are inorganic. These facts together const.i.tute an irresistible presumption that ultimately mind and matter must obey the same laws.

But this is not the desired conclusion. The conclusion desired is that mind must obey matter's laws. The fact that mind and matter obey the same ultimate laws is a different thing, and rather indicates that even the redistribution of matter and motion requires ultimately some other explanation than merely mechanical laws afford. To the religious mind it is quite intelligible that mind and matter should obey the same laws--G.o.d's laws.

It may be said, however, that we have not done full justice to the presumption raised by the broad facts of evolution. When there was no life upon the earth, the only laws in operation must have been physical laws, and consequently the laws of life and consciousness must have been produced by the laws of matter.

Now, this argument in effect amounts to a denial of any difference between the mechanical composition and the chemical combination of bodies. Bodies when mechanically compounded continue to follow the same laws as they obey when uncompounded, and their conjoint action can be deduced and foretold from the laws to which they are subject in their separate state: "Whatever would have happened in consequence of each cause taken by itself happens when they are together, and we have only to cast up the results."[17] With chemical combination the case is quite different: the chemical compound exhibits properties and behaves in ways which are quite different from the properties and behaviour of its elements, and could not be foretold from any observation of them. Water, which is a combination of oxygen and hydrogen, exhibits no trace of the properties of either. "If this be true of chemical combinations, it is still more true of those far more complex combinations of elements which const.i.tute organised bodies, and in which those extraordinary new uniformities arise, which are called the laws of life. All organised bodies are composed of parts similar to those composing inorganic nature, and which have even themselves existed in an inorganic state; but the phenomena of life, which result from the juxtaposition of those parts in a certain manner, bear no a.n.a.logy to any of the effects which would be produced by the action of the component substance considered as mere physical agents.... The tongue, for instance, is, like all other parts of the animal frame, composed of gelatine, fibrin, and other products of the chemistry of digestion, but from no knowledge of the properties of those substances could we ever predict that it could taste, unless gelatine or fibrin could themselves taste; for no elementary fact can be in the conclusion which was not in the premises."[18]

What is thus true of physiology and of those chemical combinations on which it is based, is true also of sociology and the psychological facts on which it is based. "When physiological elements are combined, the combination reveals properties which were not appreciable in the separate elements. The increasingly complex combination or a.s.sociation of organic elements may produce an entirely special set of phenomena....

Their combination exhibits something more than the mere sum of their separate properties. Thus, no knowledge of man as an individual would enable us to forecast all the inst.i.tutions which result from the a.s.sociation of men and which can only manifest themselves in social life."[19]

It is clear, then, that the mechanical theory of evolution can only maintain itself by obliterating the distinction between mechanical juxtaposition and chemical combination. The obstacles which stand in the way of this obliteration, at the outset, are two. First, the behaviour of a chemical compound bears no resemblance to the behaviour of its const.i.tuents when separate. Next, the laws of the compound cannot be deduced or exhibited as consequences of the laws of the separate elements. To these two objections it may be replied, first, that though the compound bears no resemblance to its separate const.i.tuents, the character of every aggregate must be determined by that of its component parts; and, next, that with more knowledge we shall come to see the way in which the laws of the separate components generate the law of the whole. Perhaps, by way of ill.u.s.tration, we may employ an a.n.a.logy. A number of bricks can be placed on one another to form a cube; a number of cannon b.a.l.l.s will form a pyramidical pile. The aggregate of bricks resembles in shape the separate bricks; the aggregate of b.a.l.l.s does not resemble a ball in shape. Yet the pyramidical shape of the pile of cannon b.a.l.l.s is as certainly determined by the shape of the separate b.a.l.l.s, as the cubical shape of the heap of bricks is determined by that of the separate bricks. Now, we do not know the geometrical structure of chemical atoms; but, on this a.n.a.logy, it is reasonable to suppose that, if we did, we should see at once that the structure of a chemical compound is dependent on, though different from, that of its elements.

So too in sociology, the aggregate, society, is not a human being, but the character of any given society is determined by the character of its individual members.

This last ill.u.s.tration, however, brings us to a fresh difficulty in the way of the mechanical theory. As is observed in the remarks quoted previously from Monsieur Bernard, the peculiar characteristic of those more intimate combinations which form the subject-matter of chemistry, physiology, and sociology is that in them the combining elements reveal properties which were not perceptible in them previous to their combination. It may be true that the character of these more intimate combinations is determined by the properties of their const.i.tuents, but it is by the properties which they reveal when in combination, not by those which are manifest in them when uncombined. Therein lies the difference between mechanical compounds and chemical combinations; and it is that difference which the mechanical theory does not account for.

The more intimate, chemical, physiological, and sociological combinations take place in virtue of properties which require the combination to reveal them. In sociology it is not the juxtaposition of individual men, but their co-operation, which makes a society. In chemistry, the formation of chemical compounds implies the affinity of the elements.

It seems, then, that the mechanical theory contains half the truth, but not the whole truth. The half-truth which it insists on is that in both mechanical and chemical combinations there is juxtaposition of the const.i.tuent elements. The half of the truth which it overlooks is that when the elements are juxtaposed in one way they develop or manifest new qualities, when juxtaposed in the other way they do not. The mechanical theory a.s.serts that the only factors in evolution are matter and the force which moves matter about: it takes into account the external factors, but leaves out the internal force or spontaneity in virtue of which things in a suitable environment develop new qualities. Doubtless the juxtaposition of the elements is a condition without which they would not manifest their new properties: the redistribution of matter and motion is a condition of evolution, but it does not const.i.tute evolution. Rather, it is the continual revelation of these new qualities which const.i.tutes evolution, chemical affinity and all its consequences in chemistry, spontaneous variation and all its consequences in the evolution of organic life.

From this point of view it becomes clear why the laws of a chemical compound neither are nor can be exhibited as consequences of or deductions from the laws of its separate const.i.tuents. The properties which the law of the compound describes are not the properties which the separate elements exhibit. The living matter of biology, the active atoms of chemistry, are not products of the lifeless, inert matter of mechanics; but are different and higher revelations of the same power which is manifested in different degrees in all. It is this progressive manifestation, and not the mere drifting about of bits of matter, which const.i.tutes evolution. The redistribution of matter and motion may be a concomitant of evolution, but it is not evolution. "The continuous adjustment of internal relations to external relations," which Mr.

Herbert Spencer[20] offers as a definition of life, may be a condition of the maintenance of an organism; but life is and means to each one of us, and to the humblest thing that breathes, much more than that. Mr.

Spencer's definition of life leaves, for instance, consciousness out, as of no account in life, and would be equally applicable to many automatic, self-adjusting machines. The definition const.i.tutes an admission that life and consciousness cannot be exhibited as a consequence of the redistribution of matter and motion. They appear at a certain (or uncertain) point in the process of redistribution, and they have as concomitants certain further redistributions; but they are neither the consequence of nor are they identical with that redistribution; nor can their laws be reduced to mere cases of the laws of matter and motion.

The doctrine that evolution consists in nothing but movements in s.p.a.ce, amounts to the a.s.sertion that we know nothing about things and men except that they move. In point of fact, we know a good deal more. We know that men think, and that the movement of thought is not a movement in s.p.a.ce. We know that the vibrations of the ether are movements in s.p.a.ce and that they are also something more: they are known to us also as sights, sounds, etc. No explanation or concise statement of the process of evolution can be satisfactory, or even scientific, which begins by denying the relevance and even the reality of the most important part of our knowledge. If the "first principles" of evolution are to be scientific, they must be inductions drawn from observation and based on some similarity in the phenomena observed, in which case, and in which case alone, they will apply to both cla.s.ses of phenomena, mental and material. If any "principle" is true of one cla.s.s alone, it is shown thereby not to be a "first principle": it is not universally applicable.

This raises the question whether there can be any first principles in this sense, whether mind and matter are, to some extent, subject to the same laws; or whether the resemblances which are sometimes drawn are not merely metaphors more or less expanded. Thus we speak of "weighty"

objections; but will anyone maintain that ideas are subject to, or exemplify, the law of gravitation? We speak of ideas as "coherent" or "incoherent"; does anyone suppose that they stick together in the same way and from the same causes as material objects cohere?

Mr. Herbert Spencer has written a chapter[21] under the t.i.tle "Society is an Organism," in which he points out many resemblances between society and an organism. But Mr. Spencer himself "distinctly a.s.serts"[22] that the resemblances imply nothing more than that in both society and organisms there is "a mutual dependence of parts." That is to say, sociology does not herein "exemplify" some of the laws of biology, but sociology and biology both exemplify certain laws which hold good wherever there is a mutual dependence of parts.

Again, Mr. Spencer says[23] that "evolution is definable as a change from an incoherent h.o.m.ogeneity to a coherent heterogeneity, accompanying the dissipation of motion and integration of matter"; and, having shown how and why the h.o.m.ogeneous and the incoherent in the domain of physics tend to become coherent and heterogeneous, he proceeds to show that there is a similar process in the evolution of knowledge, and to say "these mental changes exemplify a law of physical transformations that are wrought by physical forces."[24] Now it doubtless is a fact that with intellectual development there goes a more accurate discrimination of differences at first unnoticed, a readier perception of resemblances at first undetected, a consequent segregation and cla.s.sification of ideas, and a recognition of heterogeneity where h.o.m.ogeneity was at the first glance supposed to prevail. Doubtless, too, as a result of this process, there is greater coherency in our ideas. But is all this anything more than expanded metaphor? If it is something more, how can these mental changes "exemplify" a law of physics when ideas neither stick physically to each other nor gravitate to one another like the particles of the original, h.o.m.ogeneous, nebular ma.s.s? If mental and material phenomena can to some extent obey the same laws, and these laws are scientific inductions, there must be some resemblance between the phenomena.

That resemblance cannot be physical or spatial, because mental phenomena do not occupy s.p.a.ce, or possess weight, or exist in three dimensions. As far as one can see, it consists in two points: both cla.s.ses of phenomena (1) are objects of thought and (2) are displays of force or power. This implies that movements in s.p.a.ce are displays of the same force as is manifested in the non-spatial movements of thought. The force which is displayed in consciousness as Will appears in s.p.a.ce as motion. Both cla.s.ses of phenomena, however, are not only displays of force, but also objects of thought. The reality of a phenomenon of either cla.s.s consists in its being the manifestation of Will to or in consciousness.

The reality of the two cla.s.ses is co-extensive with their similarity, and is the sole foundation for any true inferences or justifiable generalisations about them.

If the law of "the instability of the h.o.m.ogeneous" is a first principle, and is a scientific induction based upon a real similarity between the mental and material phenomena of which it is offered as an explanation, it becomes interesting to inquire how far the similarity extends. In the case of mental evolution the essential feature of the process is that the mind gradually comes to perceive resemblances and to discriminate differences which, though they were present all the time, were not at first appreciable. In other words, the apparently h.o.m.ogeneous was, from the beginning, really heterogeneous. Now this fact, which is true in the sphere of mental evolution, finds its exact parallel in the evolution of the material universe, if the account given above of mechanical compounds and chemical combinations be true. What appears first in the process of evolution, and is exemplified by mechanics, is matter apparently inert. But when the particles of this apparently inert matter enter into chemical combinations with one another they reveal a fresh set of properties, quite different from those exhibited by them previous to their combination; and, when they enter into physiological relations, they display yet further additional properties. This progressive manifestation it is, and not the accompanying "dissipation of motion and integration of matter," which const.i.tutes evolution in the material world, and finds its exact parallel in mental evolution. In both cases we have Will manifested as object of thought; and in both cases we judge most truly of that which is manifested when we judge it by its most complete manifestation. In both cases the apparent h.o.m.ogeneity is not the ultimate fact underlying everything, but is only the first-fruits of that which is yet to come.

FOOTNOTES: