WE see, then, how the existence of Organs separated from Function and of structures without immediate use, find their natural place among all the other phenomena of the world. They do not show that" Law" is ever superior to Will, or can ever assert, even for a moment, an independence of its own. On the contrary, they show as nothing else can show, the patient movements, and the incalculable years, through which material laws have been made to follow the steps of Purpose.
But then let us remember this: these discoveries in Physiology, though they are helpless to prove that Law has ever been present as a Master, are eminently suggestive of the idea that Law has never been absent as a Servant:-that as in governing the world, so in forming it, [217/218] material forces have been always used as the instruments of Will.
It is no mere theory, but a fact as certain as any other fact of Science, that Creation has had a History. It has not been a single act, done and finished once for all; but a long series of acts a work continuously pursued through an inconceivable lapse of time. It is another fact equally certain, that this work, as it has been pursued in Time, so also it is a work which has been pursued by Method. There is an "observed Order of facts" in the history of Creation both in the organic and in the inorganic world. I speak here, however, of the organic world alone, and chiefly of those higher Forms which are the seat of Animal Life. In these there is an observed Order in the most rigid scientific sense, that is,phenomena in uniform connexion, and mutual relations which can be made, and are made, the basis of systematic classification. These classifications are imperfect, not because they are founded on ideal connexions where none exist, but only because they fail in representing adequately the subtle and pervading Order which [218/219] binds together all living things. But the Order which prevails in the existing world is not the only Order which has been recognised by science. A like Order has prevailed through all the past history of Creation. Nay, more; it has, I think, been clearly ascertained, not only that relations similar to those which now exist have existed always among all the animals of each contemporary Creation, but that Order of a like kind has connected with each other all the different Creations which were successively introduced. In almost all the leading Types of Life which have existed in the different geological ages, there is an orderly gradation connecting the Forms which were becoming extinct with the Forms which were for the first time appearing in the world. It is still disputed by some geologists, whether we have certain evidence that this gradation has been the gradation of a rising scale-of progressive Creations from lower to higher Types. But this dispute is maintained only on the ground, that we cannot safely trust to negative evidence. It is an unquestionable fact, that so far as this kind of evidence can go, it does testify to the successive [219/220] introduction of higher and higher Forms of Life. Very recently, a discovery has been made, to which Mr Darwin only a few years ago referred, as "a discovery of which the chance is very small," viz., of fossil Organisms in beds far beneath the lowest Silurian strata. This discovery has been made in Canada — in beds far down, near the bottom even, of the rocks hitherto termed "Azoic." But what are the Forms of Life which have been found here? They belong to the very lowest of living types, — to the "Rhizopods." So far as this discovery goes, therefore, it is in strict accordance with all the facts previously known, — that as we go back in time, the lose, one after another, the higher and more complex organisms, — first, the Mammalia; then, the Vertebrata; and now lastly, even the Mollusca. It is in accordance, too, with another fact which has been observed before, viz., that particular Forms of Life have attained, at particular epochs, a maximum development both in respect to size and distribution, the favourites, as it were, of Creation for a time. These earliest Rhizopods seem to have been of enormous size and developed on an enormous scale, since there is good reason [220/221] to believe that beds of immense thickness are composed of their remains. All that is new in this discovery is the vast extension which it gives in Time to the same rules which had been already traced through ages which we cannot number.
Then, there is another observed Order. For each Class of animal some definite Type or pattern has been adhered to; and the modifications of that Type have been gradual and successive. In many cases the science of fossil remains enables us to trace the intermediate Forms through which existing animals can be connected with animals long since extinct. It must be remembered that the fact of this connexion is quite a separate thing from any theory as to its physical cause. Professor Owen pointed out some years before the publication of Mr Darwin's theory, the existence of fossil animals which showed an increasing approximation to the forms of the Horse and of the Ox: and he showed that this approximation was related in Time, as it seemed to be in Purpose, with the coming need of them for the service and use of Man. These are the facts on which the idea of "Creation [221/222] by Law" is founded. Let us look a little nearer what this idea is, and what it involves. It is an idea much vaunted by some men, much feared by others. Perhaps it may be found; on closer investigation, that they are fearing or worshipping, as the case may be, an idol of the imagination.
It being certain that Creation exhibits an Order of facts which can be so clearly defined and traced, it follows, that at least in this first sense of the word, Creation has been by Law. We are, there. fore, led on to the farther question, whether Law in any other sense can be traced or detected in the work of Creation? Is the observed Order which prevails in the organic world an Order of which we can even guess the physical cause? Is it an Order which contains within itself any indications of the Force or combination of Forces which have been concerned in producing it?
In considering this question, there is one thing to be observed at the outset. It is certain that nothing is known, or has been even guessed at, in respect to the history and Origin of Life, which corresponds with Law in its strictest and most [222/223] definite sense. We have no knowledge of any one or more Forces — such as the Force of Gravitation, or of magnetic attraction and repulsionto which any one of the phenomena of Life can be traced. Far less have we any knowledge of any such laws which can be connected with the successive creation or development of new Organisms. Professor Huxley, in a recent work,1 has indeed spoken of " that combination of natural forces which we term Life." But this language is purely rhetorical. I do not mean to say that Life may not be defined to be a kind of Force, or a combination of Forces. All I mean is, that we know nothing of any of these forces in the same sense in which we do know something of the Force of Gravity, or of Magnetism, or of Electricity, or of Chemical Affinity. These are all more or less known, not, indeed, in respect to their ultimate nature, but in respect to certain methods and measures of their operation. No such knowledge exists in respect to any of the Forces which have been concerned in the development of Life. No man has ever pretended to get such a view of any [223/224] of these as to enable him to apply to them the instruments of his analysis, or to trace in their working any definite relations to Space, or Time, or Number.
Since, then, laws, in this most definite sense of the word, have not been discovered in the existing phenomena, or in the past history of Organic Life, let us look a little closer at the ideas which these phenomena have suggested to the mind of those who have speculated on the Origin and Development of Species.
There is one idea which has been common to all theories of Development, and that is the idea that ordinary generation has somehow been producing, from time to time, extraordinary effects and that a new Species is, in fact, simply an unusual birth. It is worthy of observation, that the earlier forms in which the theory of Development appeared, did suggest something more nearly approaching to a Law of Creation than is contained in the later form which that theory has assumed in the hands of Mr Darwin. The essential idea of the theory of Development, in its earlier forms, was, that modifications of structure arose somehow [224/225] by way of natural consequence from the outward circumstances or physical conditions, which required them, and from the living effort of Organism sensible in some degree of that requirement. Now, inadequate and even grotesque though this idea may be as explaining the Origin of new Species, it cannot be denied, that it makes its appeal to a process which, at least to a limited extent, does operate in producing modifications of organic structure. For example, the same species of Mollusc has often a shell comparatively weak and thin, or a shell comparatively robust and strong, according as it lies in tranquil or in stormy water. The shell which is much exposed needs to be stronger than the shell which is less exposed. But it is obvious that the mere fact of the need cannot supply the thing needed, unless by the adjustment of some machinery for the purpose. How the vital forces of the Mollusc can thus be made to work to order, under a change of external conditions, we do not know. But we do know, as a matter of fact, that the shell is thickened and strengthened, according as it needs resisting power. This result does not appear to arise from any [225/226] difference in the amount of lime held in solution in the water, but upon some power in the secreting organs of the animal to appropriate more or less of it, according to its own need. The effects of this power are seen where there is no difference of condition except difference of exposure. It is said that they are observable, for example, in the shells which lie on the different sides of Plymouth Breakwater, — the sheltered side and the exposed side. The same power of adaptation is seen in many other forms. Trees which are most exposed to the blast are the most strongly anchored in the soil. Limbs which are the most used are the most developed. Organs which are in constant use, are strengthened, whilst organs in habitual disuse have a tendency to become weaker.
All these results arise by way of natural consequence. How shall we describe them? Shall we say that they are the result of Law? We may safely do so, remembering only that by Law, in this sense, we mean nothing but the co-operation of different natural Forces, which, under certain conditions, work together for the [226/227] fulfilment of an obvious intention. Of the nature of those Forces we know nothing; nor is it easy to conceive how they have been so co-ordinated as to produce effects fitting with such exactness into the conditions requisite for the preservation of Organic Life. If there were any evidence that by the same means new Forms of Life could be developed from the old, I cannot see why there should be any reluctance to admit the fact. It would be different from anything that we see; but I do not know that it would be at all less wonderful, or that it would bring us much nearer than we now stand to the great mystery of Creation. The adaptation and arrangement of natural forces, which can compass these modifications of animal structure, in exact proportion to the need of them, is an adaptation and arrangement which is in the nature of Creation. It can only be due to the working of a power which is in the nature of Creative Power.
We are so accustomed to these and other similar phenomena, and to hide our own ignorance of their cause, by describing them as the result of "Law," that we forget what a [227/228] multitude of natural Forces must be concerned in their production, and what complicated adjustments of these amongst each other for the accomplishment of Purpose. It is purely, therefore, in my view, a question of evidence, whether this particular law of adaptation has or has not been the means of introducing new Forms of Life. There is no evidence that it has. So far as we know, this power of self-adaptation, wonderful as it is, has a comparatively limited application; when that limit is outrun by changes in outward conditions, which are too great or too rapid, whole Species die and disappear. Nevertheless, the introduction of new Species to take the place of those which have passed away, is a work which has been not only so often, but so continuously repeated, that it does suggest the idea of having been brought about through the instrumentality of some natural process. But we may say with confidence, that it must have been a process different from any that we yet know — a process not the same as that, obscure as this is, which produces the lesser modifications of Organic Forms.
It has not, I think, been sufficiently observed, [228/229] that the theory of Mr Darwin does not address itself to the same question, and does not even profess to trace the Origin of new Forms to any definite law. His theory gives an explanation, not of the processes by which new Forms first appear, but only of the processes by which, when they have appeared, they acquire a preference over others, and thus become established in the world. A new Species is, indeed, according to his theory, as well as with the older theories of Development, simply an unusual birth. The bond of connexion between allied specific and generic Forms, is in his view simply the bond of Inheritance. But Mr Darwin does not pretend to have discovered any law or rule according to which new Forms have been born from old Forms. He does not hold that outward conditions, however changed, are sufficient to account for them. Still less does he connect them with the effort or aspirations of any Organism after new faculties and powers. He frankly confesses that "our ignorance of the laws of variation is profound;" and says, that in speaking of them as due to chance, he means only to acknowledge plainly our ignorance of the [230] cause of each particular variation."2 Again he says — " I believe in no law of necessary development."
This distinction between Mr Darwin's theory and other theories of Development, has not, I think, been sufficiently observed. His theory seems to be far better than a mere theory — to be an established scientific truth — in so far as it accounts, in part at least, for the success and establishment and spread of new Forms when they have arisen. But it does not even suggest the law under which, or by which, or according to which, such new Forms are introduced. Natural Selection can do nothing except with the materials presented to its hands. I It cannot select except among the things open to selection. Natural Selection can originate nothing; it can only pick out and choose among the things which are originated by some other law. Strictly speaking, therefore, Mr Darwin's theory is not a theory on the Origin of Species at all, but only a theory on the causes which lead to the relative success or failure of such new Forms as may be born into the world. [230/231]
It is the more important to remember this distinction, because it seems to me that Mr Darwin himself frequently forgets it. Not only does he speak of Natural Selection "producing" this and that modification of structure, but he undertakes to affirm of one class of changes that they can be produced, and of another class of changes that they cannot be produced, by this process Now, what are the changes for the preservation of which Natural Selection does, in some sense, account? They are such changes, and these only, as are of some direct use to the Organism in the "struggle for existence." Any change which has not this direct value, is not provided for in the theory. All structures, therefore, are unaccounted for — not only as respects their origin, but even as respects their preservation — in which the variations have no other value than mere beauty or variety.
Accordingly, Mr Darwin is tempted, as I have already had occasion to observe, to deny that any such structures exist in Nature. Any theory of which this denial is really a necessary part is self-condemned. Yet a theory may be good [231/232] as accounting for the preservation of some structures, although it fails to account for the preservation of others. And so the fact that Natural Selection cannot have operated on structures of mere beauty and variety is no proof that the theory of Natural Selection is false, but only that it is incomplete. It does not account for the origin of any structure; and it accounts for the preservation of only a certain number. Surely, then, Mr Darwin assigns to his "law" of Natural Selection a range far wider than really belongs to it, when, on the strength of it, he denies that beauty for its own sake can be an end or object in Organic Forms. He says — "This doctrine, if true, would be absolutely fatal to my theory."3 Why should this be fatal to his theory, except on the supposition that Natural Selection gives a complete account both of the Origin of new Forms, (of which, in reality, it gives no account at all,) and of their preservation, of which it does give some account, but one which is only partial? I dwell on this, because it lies at the very root of the question, how far Mr Darwin's theory can be said to suggest anything in the nature of a Creative [232/233] Law of a kind to explain the Method which has been followed in the introduction of new Forms.
We may test this question by bringing to bear upon it some particular example of specific variation. I select for this purpose one example, which will illustrate the subject better than any abstract discussion. It is the case of the Humming Birds.
This group of birds seems to exhibit, in the most striking form, not a few of those mysteries of Creation which at once tempt us to speculate on the Origin of Species, and at the same time confound every endeavour to bring it into relation with any process which we know or can conceive. In the first place, they are sharply defined from all other forms in that Class of the animal kingdom to which they belong. It is most difficult to say what is their nearest affinity, and the nearest, when it is found, is very distant. Secondly, they are absolutely confined to one Continent of the Globe. In the third place, the various Species as amongst themselves are very closely united, ranging, indeed, over a great variety of forms, but for the most part connected with each other by very [223/234] nice gradations. In the fourth place, there are, so to speak, some gaps in the scale, which suggest that some Species have either been lost, or have not yet been discovered. In the fifth place, each of these Species, however nearly allied to some other, appears to be absolutely fixed and constant, there being not the slightest indication of any mixture-of any hybrid forms. In the sixth place, there is the most wonderful adaptation of special organs for the performance of special functions, and for the relation of these organs to particular structures in the vegetable kingdom. In the seventh place, there is a development, for which, in extent and variety, there is no parallel in the world, of structures designed for mere ornament, and entirely separate from any other known or conceivable use.
A few words on some of these characters will show their separate and joint bearing on the idea of Creation by Law.
In the first place, then, the absolute distinctiveness from all others of this Family of birds, coupled with its immense extent, gives the idea of some common bond, some physical cause, to which such [234/235] an identity in physical characters must be due. This identity prevails not only in such essential matters as the structure of the bill and tongue, in the form of the feet and of the wings, in the habits of flight, in the nature of the food, but runs also into some very curious details, as, for example, in the number of feathers in the tail and in the wings, which are constant numbers — adhered to even when some of the feathers, not being used even for ornament, are reduced almost to rudiments. But under degrees of development which are very variable, the number is invariable. This identity of structure is the more remarkable from the immense extent of the group which it characterises. There are now known to science no less than about 430 different species of Humming Bird; and it cannot be doubted that many more remain to be discovered among the immense forests and mountain ranges of Central America.
Now, what is the bond that unites so closely, in a common structure, all the forms of this great Family of birds? We think it a sufficient explanation sometimes of the likeness of things, that they are made for a common purpose. And so it is [235/236] an explanation in one sense, but not in another. It gives the reason why likeness should be aimed., at, but not the cause or the means through which it has been brought about. Sameness in the purpose for which things are intended, is a reason why those things should be made alike; but it is not explanation of the process to which the common aspect is due. It is an explanation of the "why", but it is no explanation of the "how." Purpose is attained in Nature through the instrumentality'; of means; and community of aspect in created things suggests the idea of some common process in the creative work. Thus, the likeness which is due to common parentage serves the most important purposes; but it is not the less the result of ay physical cause, out of which it arises by way of natural consequence. The likeness of the Humming Birds to each other suggests this kind of cause. It is true that the organs which it principally affects are specially adapted for a special habit of life. They are fitted to enable the bird to feed on the nectar, and the insects which frequent the nectar of flowers, or the leaves or bark of trees. But there are flowers and insects in [236/237] abundance in other quarters of the globe where there are no Humming Birds.
And here we come on the curious facts of geographical distribution,-a class of facts which, as much as any other, suggest some specific methods as having been followed in the work of Creation. Humming Birds are absolutely confined to the great Continent of America with its adjacent islands. Within those limits there is every range of climate, and there are particular species of Humming Bird adapted to every region where a flowering vegetation can subsist. It is therefore neither climate nor food which confines the Humming Birds to the New World. What is it, then? The idea of "centres of Creation" is at once suggested to the mind. It seems as if the Humming Birds were introduced at one spot, and as if they had spread over the whole Continent which was accessible to them from that spot. They are absent elsewhere, simply because from that spot the other Continents of the world were inaccessible to them. But if these ideas are suggested to the mind by the general aspect of this family as a whole, they are [237/238] strengthened by some of the facts which we discover when we examine and compare with each other the genera and species of which it is composed. There is a beautiful gradation between the different genera and the different species: — much so, that it has been found impossible t divide the Humming Birds into more than two sub-families, from the absence of sufficiently wellmarked divisions. And yet, on the other hand, they cannot be arranged in anything like a continuous series, because some links appear to be missing in the chain.
But these general facts terminate in nothing more definite than a vague surmise. When we enter farther into details, we feel at once how little they agree with any physical law which is known or even conceivable by us. If the likeness which prevails in the whole group reminds us of the likeness which is due to community of blood, it is equally true that the differences between the species are totally distinct both in kind and degree from the variation which we ever see arising among the offspring of the same parents. Let us look at what these differences are. The generic [238/239] and specific distinctions between the Humming Birds are mainly of two kinds, — 1st, Differences in the form of essential organs, such as the bill and the wings; 2d, Differences in those parts of the plumage which are purely ornamental. Now, of these two kinds of variation, the only one on which the law of Natural Selection has any bearing at all, is the first. And on that kind of variation, the only bearing which Natural Selection has is this — that if any Humming Bird were born with a new form of bill, or a new form of wing, which enabled it to feed better and to range farther, then, that improved bill and wing would naturally tend to be perpetuated by ordinary generation. This is unquestionably true; but it really does not touch the facts of the case. The bills and wings of the, different genera do not differ from each other in respect of any comparative advantage of this kind, but simply in respect to variety corresponding with the variety of certain vegetable Forms. One form of bill is as good as another, but some forms are adapted to some special class of flower. Some bills, for example, are formed of enormous length, specially adapted to obtain access to the nectar [239/240] chambers of long tubular flowers, such as the Brugmansia. Some, on the other hand, as if to show that the same end may be attained by different means, obtain access to the same flowers by a shorter process, and pierce the bases of the corolla instead of seeking access by the mouth. Some have bills bent downwards like a sickle, adapted to searching the bark of Palm-trees for the insects hid under the scaly covering; others have bills curved in the opposite direction, fitted, apparently, to the curious construction of some of the great family of Orchids so immensely developed in the forests of Central America. Some have bills equally well adapted for searching a vast variety of flowers and blossoms, and these, accordingly, migrate with the flowering season, and issuing from the great stronghold of the family in tropical America, spread like our own summer birds of passage, northwards to Canada, and southwards to Cape Horn, in the corresponding seasons of the year. In contrast with these species of extended range, there are many species whose habitat is confined, perhaps to a single mountain, and there are a few which never have been seen [240/241] beyond the edges of some extinct volcano, whose crater is now filled with a special flora. Many of the great mountains of the Andes have each of them species peculiar to themselves. On Chinlborazo and Cotopaxi, and other summits, special forms of Humming Birds are found in special zones of vegetation even close up to the limits of perpetual snow. Again, many of the Islands have species peculiar to themselves. The little island of Juan Fernandez, 300 miles from the mainland, has three species peculiar to itself, of which two are so distinct from all others known, that they cannot for a moment be confounded with any of them.
It is impossible not to see, in such complicated facts as these, that the creation of new Species has followed some plan in which mere variety has been in itself an object and an aim. The divergence of form is not a divergence which can have arisen by way of natural consequence, merely from comparative advantage and disadvantage in the struggle for existence. Bills highly specialised in form are certainly not those which would give the greatest advantage to birds which [241/242] have equal access to the abundant Flora of an immense Continent. Some form of bill adapted to the probing or piercing of all flowers with almost equal ease, would seem to be the form most favourable to the multiplication and spread of Humming Birds. Continued approximation to some common type would seem to be quite as natural, and a much more advantageous kind of change as regards advantage in the struggle for existence, than endless divergence and special adaptation to limited spheres of enjoyment. At all events, we may safely say that mere advantage, in Mr Darwin's sense, is not the rule which has chiefly guided Creative Power in the Origin of these new Species. It seems rather to have been a rule having for its object the mere multiplying of Life, and the fitting of new Forms for new spheres of enjoyment, according as these might arise out of corresponding changes in other departments of the organic world.
If, now, we turn to the other kind of specific distinction between Humming
Birds, viz., that which consists in differences in the mere colouring and disposition
of the plumage, we shall find the same phenomena still more remarkable. In [242/243] the first place, it is to be observed of the whole group that there is no connexion
which can be traced or conceived between the splendour of the Humming Birds
and any function essential to their life. If there were any such connexion,
that splendour could not be confined, as it almost exclusively is, to one sex.
The female birds are of course not placed at any disadvantage in the struggle
for existence by their more sombre colouring. Mere utility in this sense, therefore,
can have had no share in determining one of the most remarkable of all the characteristics
of this family of birds. Those who by special study have laid their mind alongside
of the Mind of Nature in any of her Provinces, have generally imparted to them
a true sense, so far as it goes, in the interpretation of her mysteries. Let
us then hear what Mr Gould says on this point: — "The members of most of the genera have certain parts of their plumage fantastically decorated; and in many instances most resplendent in colour. My own opinion is, that this gorgeous colouring of the Humming Birds has been given for the mere purpose of ornament, and for no other purpose of [243/244] special adaptation in their mode of life; in other words, that ornament and beauty, merely as such, was the end proposed."5 Different parts of the plumage
have been selected in different genera as the principal subject of ornament.
In some, it is the feathers of the crown worked into different forms of crest;
in some, it is the feathers of the throat, forming gorgets and beards of many
shapes and hues; in some, it is a special development of neck plumes, elongated
into frills and tippets of extraordinary form and beauty. In a great number
of genera the feathers of the tail are the special subjects of decoration, and
this on every variety of plan and principle of ornament. In some, the two central
feathers are most elongated, the others decreasing in length on either side,
so as to give the whole the wedge form. In others, the converse plan is pursued,
the two lateral feathers being most developed, so that the whole is forked after
the manner of the common Swallow. In others, again, they are radiated, or pointed
and sharpened like thorns. In some genera there is an extraordinary development
of one or two [244/245] feathers into plumes of enormous length, with flat or spatulose terminations.
Mere ornament and variety of form, and these for their own sake, is the only
principle or rule with reference to which Creative Power seems to have worked
in these wonderful and beautiful birds. And if we cannot account for the differences
in the general style and plan of ornament followed in the whole group, by referring
them to any sort of use in the struggle for existence, still less is it possible
to account, on this principle, for the kind of difference which separates from
each other the different species in each of the genera. These differences are
often little more than a mere difference of colour. The radiance of the ruby
or topaz in one species, is replaced perhaps by the radiance of the emerald
or the sapphire in another. In all other respects the different species are
sometimes almost exact counterparts of each other. As an example, let me refer
to the two species figured by Mr Gould as the Blue-tailed and the Green-tailed
Sylphs; and also
One very curious example of variety for the sake of ornament may be mentioned in connexion with this wonderful family of Birds. It is a lawin the sense of an observed order of facts-regulating the ornament of Humming Birds, that where white is introduced into the colouring of the tail feathers, it is not applied to the central feathers, [246/247] but is confined to the marginal feathers on either side. There is, however, one species (UrosticteBengamini) recently discovered which affords the only example yet known of a departure from this rule. It is a species in which white is one of the principal ornaments of the Bird, and is used in places where it can be placed in conspicuous contrast with the darkest tints. Tufts and lines of purest white shine among the greens and violets of the neck and head; whilst, in exquisite harmony with this, the four central feathers of the tail are alone dipped, as it were; in a solid glaze of the same white, and the marginal feathers on either side are kept wholly dark. Then, as if to mark with emphasis the meaning of this departure from the ordinary rule, it is a departure confined to the ornamented sex; and the Female Form of the same species follows the ordinary law — white being introduced in the marginal feathers, and in these alone.
Now, what explanation does the law of Natural Selection give-I will not say of the origin, but even of the continuance and preservation-of such specific varieties as these? None whatever. A crest of topaz is no better in the struggle for existence [247/248] than a crest of sapphire. A frill ending in spangles of the emerald is no better in the battle of life than a frill ending in the spangles of the ruby. A tail is not affected for the purposes of flight, whether its marginal or its central feathers are decorated with white. It is impossible to bring such varieties into relation with any physical law known to us. It has relation, however, to a Purpose, which stands in close analogy with our own knowledge of Purpose in the works of Man. Mere beauty and mere variety, for their own sake, are objects which we ourselves seek when we can make the Forces of Nature subordinate to the attainment of them. There seems to be no conceivable reason why we should doubt or question, that these are ends hand aims also in the Forms given to living Organisms, when the facts correspond with this view, and with no other. In this sense, we can trace a creative Law,-that is, we can see that these Forms of Life do fulfil a purpose and intention, which we can appreciate and understand.
But then it may be asked, has this purpose and intention been attained without the use of means? [248/249] Have no physical laws been used, whereby these new forms of beauty have been evolved, the one from the other, in a series so wonderful for its variety in unity, and its unity in variety? I am not now seeking to answer this question in the negative. All I say is, that the physical laws which are made subservient to this purpose are entirely unknown to us. That particular combination of a great many natural laws, which Mr Darwin groups under the name of Natural Selection, does not in the least answer the conditions which we seek in a law to account for either the origin or the spread of such creatures as the various kinds of Humming Birds. On the other hand, if I am asked whether I believe that every separate Species has been a separate creation-not born, but separately made-I must answer, that I do not believe it. I think the facts do suggest to the mind the idea of the working of some creative Law, almost as certainly as they convince us that we know nothing of its nature, or of the conditions under which it does its glorious work. Our experience of the existing Order of Nature is, that the young of each species repeat the form and the [249/250] colours of their parent, and that even where variations occur, they are inconstant, and tend to disappear. We have no knowledge, for example, that from the eggs of the Blue-tailed Sylph a pair of Green-tailed Sylphs can ever be produced. We have no reason to believe that a species of Lophornis with a tippet of emerald spangles, can ever hatch out a pair of young adorned with spangles of some other gem. And yet we cannot assert that such phenomena are impossible, nor can it be denied that, as a matter of speculation, this process is natural and easy of conception, as compared with the idea of each Species being separately called into existence, out of the inorganic elements of which its body is composed.
Such new births — if they do take place — would perfectly fulfil, I think, the only idea we can ever form of new creations. For example, it would appear that every variety which is to take its place as a new Species must be born male and female; because it is one of the facts of specific variation in the Humming Birds, that although the male and female plumage is generally entirely different, yet the female of each Species is as distinct from [250/251] the female of every other, as the male is from the male of every other. If, therefore, each new variety were not born in couples, and if the divergence of Form were not thus secured in the organisation of both the sexes, it would fail to be established, or would exhibit for a time the phenomena of mixture, and terminate in reversion to the original type. Now here again we have the emphatic declaration of Mr Gould, that among the thousands of specimens which have passed through his hands, from all the genera of this great family, he has never seen one case of mixture or hybridism between any two Species, however nearly allied. But this passage is so important, that I quote it entire.
"It might be thought by some persons that four hundred species of birds so diminutive in size, and of one family, could scarcely be distinguished from each other; but any one who studies the subject, will soon perceive that such is not the case. Even the females, which assimilate more closely to each other than the males, can be separated with perfect certainty; nay, even a tail-feather will be sufficient for a person well versed in the subject to say to what genus and [251/252] species the bird from which it has been taken belongs. I mention this fact to show that what we designate a Species has really distinctive and constant characters; and in the whole of my experience, with many thousands of Humming Birds passing through my hands, I have never observed an instance of any variation which would lead me to suppose that it was the result of a union of two species. I write this without bias, one way or the other, as to the question of the Origin of Species. I am desirous of representing Nature in her wonderful ways as she presents herself to my attention at the close of my work, after a period of twelve years of incessant labour, and not less than twenty years of interesting study."6.
If, therefore, new Species are born from the old, it is not by accidental mixture; it is not by the mere nursing of changes advantageous in the battle of life; it must be from the birth of some one couple, male and female, whose organisation is subjected to new conditions corresponding with each other, and having such force of self-continuance as to secure it against reversion. It matters [252/253] not how small the difference may be from the parent Form; if that difference be constant, and if it be associated with some difference equally constant in the female Form, it becomes at once a new Species. There are some cases mentioned by Mr Gould which may possibly be examples of the first founding of a new Species. In the beautiful genus Cynczlztlazis, he tells us that there are some local varieties near Bogota, in which the ornament is partially changing from blue to green; and it is a curious fact that this variation appears to be taking effect under the direction of some definite rule or" law,"-inasmuch as it is only the eight central feathers of the tail which are tipped with the new colour. Mr Gould expressly says of one such variety from Ecuador, that it possesses characters so distinctive as to entitle it, in his opinion, to the rank of a separate Species. The very discussion of such a question shows the possibility of new births being the means of introducing new Species. But my object here is simply to point out that Mr Darwin's theory offers no explanation of such births, either as respects their origin or their preservation, neither [253/254] does it even approach to tracing these births to any physical law whatever. It fails also to recognise, even if it does not exclude, the relation which the birth of new Species has to the mental purpose of producing mere beauty and mere variety. Nevertheless it may be true that ordinary generation has been the instrument employed; but if so, it must be employed under extraordinary conditions, and directed to extraordinary results.
It will be seen, then, that the principle of Natural Selection has no bearing whatever on the Origin of Species, but only on the preservation and distribution of Species when they have arisen. I have already pointed out that Mr Darwin does not always keep this distinction clearly in view, because he speaks of Natural Selection "producing" organs, or "adapting" them. It cannot be too often repeated that Natural Selection can produce nothing whatever, except the conservation or preservation of some variation otherwise originated. The true Origin of Species does not consist in the adjustments which help varieties to live and to prevail, but in those previous adjustments which cause those varieties to be born at [254/255] all. Now what are these? Can they be traced or even guessed at? Mr Darwin has a whole chapter on the Laws of Variation;7. and it is here if anywhere that we look for any suggestion as to the physical causes which account for the Origin as distinguished from the mere Preservation of Species. He candidly admits that his doctrine of Natural Selection takes cognisance of variations only after they have arisen, and that it regards those variations as purely accidental in their origin, or in other words, as due to chance. This, of course, he adds, is a supposition wholly incorrect, and only serves "to indicate plainly our ignorance of the cause of each particular variation." Accordingly, the Laws of Variation which he proceeds to indicate are merely, for the most part, certain observed facts in respect to Variation, and do not at all come under the category of Laws, in that higher sense in which the word Law indicates a discovered method under which Natural Forces are made to work. There is, however, in this chapter one Law which approaches to a Law in the higher sense. Mr Darwin, whilst candidly confessing our [255/256] profound ignorance of the cause or origin of varieties, yet groups together a great class of facts as connected by a tie which he calls the" Correlation of Growth." Now what is this law-this observed Order of facts? It is that variation in one part of an organism is, as a rule, accompanied with corresponding variations in other parts, and especially in those parts which are"homologous," that is to say, which occupy the same relative place in the general Plan.
This, however, is but a very imperfect definition of the vast Order of mysterious facts which are covered by the words" Correlation of Growth." The fundamental idea which these words express is an Idea of wider and deeper significance in Nature, than Mr Darwin seems to have perceived. There is a co-relation between all natural organic growths: that is to say, that any variation of form in a single part has a constant relation to other variations of form in some other part or parts of the same organism. But " relation" is a vague word. — There are many kinds of "relation" — there are indeed an infinite variety of kinds. What is the kind of relation that we detect in Correlated [256/257] Growths? It is not until we ask ourselves this question that we discover what a deep question it is-how endless are the avenues of thought and of inquiry which it opens up.
First, one relation which we detect in all variations of organic growth, is simply the relation of symmetry. This kind and degree of Correlation of Growth prevails even in the world which we call Inorganic. The corresponding sides and angles of a crystal, for example, may be said to be correlated together. The nature of this relation is geometrical and numerical. It is a relation having reference to invariable rules of number. As regards its physical cause, all we can say is, that it is the result of forces whose property it is to aggregate the particles of matter in definite forms, which forms are symmetrical, — that is to say, they are forms having an axis with equal developments on either side. Correlation of Growth, therefore, in this sense points to the work of forces, one of whose essential properties is Polarity — that is, equal and similar action in opposite directions. Now this kind of Correlation of Growth may be traced upwards from simple Minerals through all [257/258] the infinite complications of the organic world. It is unquestionably the basis of many of the Correlations of Growth prevailing in Plants and Animals. It is seen in the symmetrical arrangement of all vegetable, and of all animal Forms. A central axis is traceable in them all; and the Bilateral, or Radiated arrangement of their subordinate parts is one of the most fundamental and universal of all the Correlations of Growth.
This is one, but it is one only, of the Correlations of Growth which are constantly observed. It would lead us to expect that any change of form on one side of an animal would be accompanied by an exactly corresponding change on the other side; so that limbs on one side of the central axis, if changed at all, would change in exact and symmetrical accordance with the limbs on the opposite and corresponding side. This, accordingly, is one of the Correlations of Growth most constantly observed.
Now it will be seen that Correlation of Growth in this first and simplest sense, runs alongside, as it were, of Correlation in another and higher sense. The relation between two equal and opposite [258/259] growths, which is a relation in the first place of simple symmetry as between themselves, is always accompanied by another relation, in the second place, of correspondence or fitness as between these growths and external conditions. An organism which is developed unsymmetrically — unequally — would be not only ugly in its form, but it would be maimed and imperfect in its functions. Here, then, we see one kind, and one idea of Correlation rising above another. Two growths might be correlated as regards each other, and might yet be wanting in any corresponding correlation of fitness and of function towards outward things. But the first of these two kinds of correlation would be useless without the last. And this last is obviously the higher and more complex Correlation of the two. It is higher, not only in the sense of being more complex, but as involving an idea which lifts us at once from a lower to a higher region of thought. Growths correlated as between each other according to mere symmetry of arrangement suggest nothing, except the work of Forces with inherent Polarity of action. But growths correlated with [259/260] things outside the organism in which those growths occur, — and which can exert no physical effect upon it, — suggest at once the operation of Forces working under Adjustment with a view to Purpose.
When we see a Mineral salt crystallising under the power of a Voltaic Current, we see Correlation of Growth in its simplest form, and in visible connexion with its immediate cause. The particles of salt are marshalled in a constant Order-an Order the principle of which is some central axis with branches and branchlets grouped around it in equal and exquisite arrangement. Wonderful as this arrangement is, it suggests no other question to the mind than that which may be asked in respect to the ultimate nature and source of Polarity in Magnetic Force. But when we see two growths in an organism which not only are correlated to each other with reference to a centre, but are correlated also to external things with reference to Function — we see something which raises questions altogether different in kind. We have passed at once from the region of the What, and the How, into the region of the Why. The one kind of Correlation has [260/261] reference to Physical Causes, the other kind of correlation has reference to those Mental Purposes which Physical Causes are made to serve. These two kinds of Correlation are perfectly distinct. They are as distinct as the correlation of equal pressures which a given volume of steam exerts upon the opposite sides of a Boiler is distinct from the correlation between that pressure and its conversion into the driving force of cranks and wheels, with all their adaptations for running on the rails, or for paddling in the sea. They are as distinct as the correlations of force developed in a Voltaic Battery are distinct from the adjustments which convert those forces into the means of communicating Thought.
Mr Darwin has not pointed out this distinction clearly. Indeed he does not seem to have had it in his view. He groups under one name, the Correlation of Growth, two classes of Phenomena, which are indeed always combined in fact, but which are entirely separate in idea. Correlation of Growth in one sense is that law of vital force which secures that any change in the shape of one limb in an animal shall be [262/262] accompanied by a corresponding change in all the other limbs. Correlation of Growth in the other sense, is that adjustment of those forces to the contingencies of external circumstance, which secures that all the changes which do take place shall be changes adapted to the discharge of new functions — to the fulfilment of new conditions of life-to command ever new sources of enjoyment.
Keeping, then, clearly in our view the distinction between these two different kinds of Correlation of Growth, let us look at the phenomena actually presented in the aspect and history of Organic Forms, as respects both these kinds of Correlation.
As regards the first kind of Correlation, I have referred to the law of Bilateral Symmetry as the simplest and most obvious illustration. It is a law which at once connects itself with the idea of Polarity of Force. But though this be one kind of Correlation, almost universal, and may very probably be the foundation of every other, there are many Correlations of Growth between which and mere Polarity there is no visible connexion. The truth is that all the parts of an [262/263] organism are bound together as one whole by a pervading system of correlations as intricate as they are obscure. When the organism is in health, and all its parts are working in harmony, the wonder of these correlations is not perceived. But they are brought out in a marked degree by the phenomena of disease, and also by the phenomena of monstrosity or malformation. The "sympathy" which the most distant and apparently unconnected parts of an organism show with each other when one of them is affected by disease is the index of correlations whose nature is utterly beyond the reach of our anatomy. It is the same with malformations. Mr Darwin mentions one case of curious and unintelligible — correlation — viz., that a blue iris is associated in Cats with deafness; and, again, that the tortoise-shell colour of the fur is associated with the female sex in the same animal. In like manner the bright colours, and the more conspicuous ornaments of plumage in Birds, are correlated with the male sex. So likewise are vocal organs with the wonderful gift of song. In many insects the differences of form which are correlated with the [263/264] differences of sex, are far greater than the differences which separate species and even genera. There are insects of which the male is a fly, whilst the female is a worm. There are many other cases of correlation between different growths in respect to which the nature and source of the connexion is equally unknown. For example, the complex stomachs of the Ruminant Order are uniformly associated with a particular form of hoof. Sometimes correlations the most constant and invariable are at the same time the most subtle and the most secret, because they are hid under other growths which are not so correlated and which produce total diversities of outward aspect. One very curious class of correlations is the correlation between the internal structure of the teeth in animals, and the structure of other very distant portions of their frame. There lately was, for example, in the Zoological Gardens a little animal, the Hyrax, not unlike a Rabbit in general appearance, and very like it in habit. It is the "Cony" of Scripture. Now this little animal will be found on examination to have limbs which do not terminate in a foot like a Rabbit, but in a [264/265] divided hoof of peculiar form. This hoof is in miniature like the hoof of a Rhinoceros. If next we examine the teeth of the Hyrax we shall find that the materials of these teeth are also combined in the same manner and after the same pattern as the teeth of the Rhinoceros. So it is with other parts of the same two animals. Along with the teeth and the hoofs there are certain other shapes of bones which seem to be under the same bond of likeness. Now these are Correlations of Growth between different parts of the same animal, and between the corresponding parts in two different species.
The conception, then, which we are led to form by this kind of Correlation between organic growths, is more complex than we had at first supposed. Mere Polarity of Force, leading to equal and opposite arrangement of subordinate parts, is not enough to satisfy the facts. This, indeed, may continue to be the type to which our thoughts refer, and by which we are helped to some more adequate idea of the facts. But the general impression left on the mind is this — that some One Force directs the form and structure [265/266] of every organism, so that any change in one part of it is but the index of changes which run visibly or invisibly throughout the whole. The growths between which we detect a correlation, are not really separate things connected only by the few correspondences which we may be able to detect, but are part and parcel of one operation, the result of one Force, exerting its energies through channels which we cannot see, and according to laws of which we can form but a distant and faint conception. The truth is, that Correlation in this sense is involved in the very word "Growth." Each part of every structure which is the result of growth must be correlated to every other part. This is essential to the very idea of growth, and to the very idea of an organism due to growth. When, therefore, Mr Darwin says that one of the laws on which variation of form depends is Correlation of Growth, he simply says that variations of Growth depend on growth — for all growths must be correlated.
But Correlation in this sense helps but a little way indeed in conceiving the origin of a new [266/267] Species. There might be the most minute and perfect harmony between the changes effected in an animal newly born, without those changes tending even in the most remote degree towards the establishment of a new Form of Life. In order to that establishment there must be another correlation, and a correlation of a higher kind. There must be a correlation between those changes and all the outward conditions amidst which the new Form is to be placed and live. If this correlation fails, the new Form will die. Yet, so far as we can see, this kind of correlation is without any physical cause. It is not necessarily involved, as the other kind of correlation is, in the very idea of Growth. On the contrary, it is not only entirely separable in thought, but, as we see in monstrosities, it is sometimes separated in fact. We have no conception of any Force emanating from external things which shall mould the structure of an organism in harmony with themselves. Mr Darwin freely confesses this, and says that many considerations "incline him to lay very little weight on the direct action of the conditions of life" in producing variety of Form. We [267/268] can conceive, dimly indeed, but still we can conceive how in the Humming Birds a special form of Wing shall be correlated with a special form of Bill. But we have no conception whatever how a special form of Bill should be correlated with a special form of Flower from which the Bill is to extract its food. Mr Darwin has shown how an improved Bill, when once produced, will be preserved by finding external conditions to which it is adapted. But he has not shown, and he frankly confesses he has no idea, how the adapted variation of Bill comes to be born at all.
Yet it is this higher and more complex Correlation which is the most constant and the most obvious of all the facts of Nature. In these facts we see that the forces of Organic Growth are worked under rules of close adjustment to external conditions; and that particular shapes which might seem inseparably associated, if we looked at one Genus or one Family alone, are at once disjoined where different adaptations to Function are required. Let us take another example from the great Class of Birds. If we were to look only to the family of the Anatidæ, (Ducks and Geese,) [268/269] we might suppose that there is a constant Correlation of Growth between webbed feet and spoonshaped Bills. But the real and efficient Correlation of Growth in this case is not between the spoonbill and the web-foot, but between both of these and certain external conditions of life. The web-foot is correlated to an aquatic habitat; and the spoon bill is correlated to spoon-food. And accordingly this association of form in foot and bill is at once dissolved where different external functions require a separation. In the Gulls, the Fulmars, and the Petrels the web-foot is retained, because action upon the element of water is still required; but the correlated form of Bill vanishes, and shapes altogether different are given,-shapes adapted, that is correlated, to different kinds of food, and to different methods of capture.
Again, there is another great family of Birds where some of the same forms are correlated with other forms entirely different, because of the different external Correlations which are required by Function. In the Divers the web-foot is mounted upon a flattened leg-bone, with the sharp edge set "fore and aft." Now what is this [269/270] Correlation of Growth? It is, first, the Internal Correlation of those parts to each other, but secondly and principally, it is the External Correlation of both to their function of propelling under water. The form of the foot is correlated to the function of opposing the largest possible area of resistance to that medium, exactly where, for the purpose of swimming, the maximum of resistance is required; the knife-shaped leg-bone is correlated to the function of opposing the least possible resistance, precisely where, for the same purpose, the minimum of resistance is required. In Australia we have, in the Oynithovynchus paradoxus, the webbed feet correlated with the Duck-shaped Bill in an animal which does not belong to the Class of Birds at all.
There is another case of what may be called Correlated Correlations, which brings out very clearly the distinction which is so important in the philosophy of this great subject. Feathers are a kind of covering peculiar to the Class of Birds. Under every variety of modification they have one fundamental plan — a central shaft or quill to which lateral filaments are attached. Now there is a [270/271] vast range of correlations between the different kinds of feather and the different Families or Species, and between different parts of the body in the same Species. But there are two Correlations of Growth in respect to feathers which are constant. In all cases, (excepting, of course, the Wingless Birds,) the feathers which grow from the fore-arm and finger-bones, constituting the Wings, are comparatively long, strong, tapering, elastic, and with thin lateral filaments, which filaments are closely hooked together by means of minute teeth fitting into each other, so that the whole shall form one continuous surface or web. This is a Correlation of Growth between one particular kind of feather, and one particular member of the body, which, in all Birds capable of flight, is constant, and amounts to a universal Law. Now let us contrast this with another Correlation of Growth which is equally constant. On the side of the head of all Birds, there is a patch of feathers of peculiar structure, with fine and slender shafts, and with the lateral filaments not hooked together as in the other case, but, on the contrary, always separated from each other-the whole series [271/272] forming a fine and open network spread over the surface which they cover and protect. These feathers cover the orifice of the ear, and are called the auriculars. They are correlated with the curious passages, the finely hung clapper-bones, and all the elaborate mechanism of that organ. Such are the Internal Correlations. But they are intelligible only when considered in the light shed by other correlations which are external. The wing feathers with close, continuous webs are correlated to the laws by which the passage of air may be prevented — the auricular feathers, with open unconnected webs, are correlated to the laws by which the passage of sound may be rendered easy. The one set of feathers are adapted to the active function of evoking and resisting atmospheric pressure by striking strong, yet light and elastic blows upon the air — the other set of feathers are adapted to the passive function of allowing the free access of the waves of sound into the passages of the ear. These are but a few examples out of millions. Throughout the whole range of Nature the system of Internal Correlation is entirely subordinate to the system of External [272/273] Correlation. Forms or growths which are inseparably joined with each other in one group of animals, are wholly divorced from each other in another group; whereas Forms which have adapted correlations to external conditions, are repeated over and over again across the widest gaps in the scale of Natural Affinity.
If, then, it be true that New Species are created out of small variations in the form of Old Species, and this by way of Natural Generation, there must be some bond of connexion which determines those variations in a definite direction, and keeps up the External Correlations pari passu with the Internal Correlations. Natural Selection can have no part in this. Natural Selection seizes on these External Correlations when they have come to be. But Natural Selection cannot enter the secret chambers of the womb, and there shape the new Form in harmony with modified conditions of external life. How, then, are these external correlations provided for beforehand? There can be but one reply. It is by Utility, not acting as a Physical Cause upon organs already in existence, but acting through Motive as a Mental Purposes [273/274] in contriving organs before they have begun to be. And where obvious utility does result, the only connecting Bond which can be conceived as capable of maintaining the Internal Correlations in harmony with the External Correlations, is the Bond of Creative Will giving to Organic Forces a foreseen direction. It is, in short, precisely the same bond which in all mechanism produces harmony of Structure with intended Function.
Hence it is that scientific men in seeking expression for the ultimate ideas arrived at in the course of Physical research, find themselves compelled to borrow the language of Mechanical Invention. There is no other language which conveys an impression of the facts, or of the tie by which the facts are connected with each other. In the first chapter of this work I have had occasion to point out how true this is of Mr Darwin's description of the Orchids, and of the curious functions of their structure. The correlations there are all external. But the same result appears in every other department of Science. In a remarkable paper on the" Constitution of the Universe," Professor Tyndall has occasion to speak of the non-luminous rays [274/275] of heat emitted by all incandescent bodies,rays which, though intensely hot, are altogether insensible to the eye. Now the Retina of the eye is a piece of mechanism whose Correlations are essentially External. It is the expansion of a special nerve whose function it is to be sensitive to certain particular vibrations, and to no other vibrations whatever. Light itself, therefore, is discovered to be merely a relative term — a word, in short, denoting nothing but an external Correlation between the Retina and vibrations of a certain kind and quality. Now what is the language which Professor Tyndall is constrained to use in explanation of facts so difficult of conception? It is the language of Mechanism, of mental Purpose and Design. "It is not," he says," the size of a wave which determines its power of producing light; it is, broadly speaking, the fitness of the wave to the Retina. The ethereal pulses must follow each other with a certain rapidity of succession before they can produce light, and if their rapidity exceed a certain limit, they also fail to produce light. The Retina is attuned, if I may use the term, to a certain range of [275/276] vibrations, beyond which, in both directions it ceases to be of use." These are indeed wonderful Correlations which reveal to us fittings and adjustments of which we had no previous conception: but they give us no glimmering even of knowledge as to the physical causes which have"attuned" a material organ so as to catch certain ethereal pulsations in the external world, and to make these the means of conveying to Man's Intelligence the enjoyment and the power of sight.
It will be seen, then, that when Mr Darwin speaks of the Law of Correlation of Growth as a Law which determines variation in organic growths, he is really presenting to us under one phrase two separate ideas which are radically distinct. One is the idea of different growths in the same organism, corresponding with each other in respect to arrangement, — or in respect to texture, or in respect to form, — or to some other point of comparison. The other idea is that these growths (each and all) correspond with the conditions of external Nature in such a way as to fit them for the discharge of Function with some new adaptation, and consequently with some new advantage. [276/277] In one aspect the Law of Correlation of Growth is (or at least may probably be) a Law in the strictest sense of the word; that is to say, the result of a Force acting according to its own definite modes and measures of operation. But the Law of Correlation of Growth in the other aspect, is a law only in the sense (I) of an observed order of facts; and (2) of that Order depending on Adjustment with a view to Purpose.
Many naturalists have spoken of the facts of organic likeness as sufficiently accounted for by referring them to Adherence to Type. Mr Darwin complains that this phrase, as an explanation of organic likeness, is no explanation at all, but amounts only to a re-statement of the facts in another form of language. This is true; but it is equally true of his own phrase of Correlation of Growth. "Adherence to Type" is not in the nature of a Physical Cause, but in the nature of a Mental Purpose. It is no explanation, therefore, to those faculties of the mind which seek for Methods of operation. In like manner" Correlation of Growth" in the only sense in which it is possible to connect it with the Origin of Species, [277/278] is not a physical cause, but a Mental Purpose. The physical means by which that purpose is secured remain as dark as ever, and such of them as are conceivable by us, are seen, like all other physical forces, working to order, subject to direction, and having that direction determined by foresight, forethought, and contrivance.
Correlation of Growth, in the sense of external adaptations, may be said to be the most universal of all the Laws of Nature. But it accounts for the Origin of Organic Forms only in the same sense in which it accounts for the origin of all other phenomena, which in their result exhibit adaptations, or fittings into use and service. Let us take as an example, the origin, nature, and capacities of Coal. That substance is correlated in a truly wonderful manner with the needs, the powers, and the capacities of Man. It contains within itself, in a form condensed and portable, a store of physical Force of incredible amount. The particles of one pound weight of it are held together by a Force which, when liberated and applied in the form of heat, is capable of lifting one million times its own weight to the height of [278/279] one foot.8 No other substance known to Man, is to be compared with this as a furnisher of Force. This is its function in the world. It is a function related to Man's mechanical and inventive powers, and coal has been rendered capable of discharging this function by processes of preparation which began millions of ages before Man was born. But these External Correlations are a result arising by way of natural consequence out of certain physical causes working to order, that is to say, out of Internal Correlations of Growth between Solar Heat and Vegetable Structure, and again between these and the causes which occasion interchange between sea and land. No explanation so definite as this can be given of the method in which Vital Forces are made to evolve a new Form of Life. But even if such explanation could be given, it would render no account at all of the fittings of that Form into the outward requirements of its life. These are Correlations which in their very nature belong to Mind, are the work of Mind, and are intelligible only in the light of Mind. [279/280] I do not represent this conclusion as one necessarily adverse to Mr Darwin's Theory on the Origin of Species. It is a conclusion which he would probably be willing to accept. I only desire to point out the very limited sense in which that Theory can be said to trace Creation to a"Law" at all, and how entirely inadequate that Theory is to account by any physical cause for the Origin of Species.
The only senses, therefore, in which we get any glimpse of Creation by Law are these-rst, that the close physical connexion between different Specific Forms is probably due to the operation of some Force or Forces common to them all; 2d, That these Forces have been employed and worked with others equally unknown, for the attainment of such ends as the multiplication of Life, in Forms fitted for new spheres of enjoyment, and for the display of new kinds of beauty.
Is there anything in this conclusion to conflict with such knowledge as we have from other sources' of the nature and working of Creative Power? I do not know on what authority it is that we so [280/281] often speak as if Creation were not Creation, unless it works from nothing as its material, and by nothing as its means. We know that out of the" dust of the ground," that is, out of the ordinary elements of Nature, are our own bodies formed, and the bodies of all living things. Nor is there anything which should shock us in the idea that the creation of new Forms, any more than their propagation, has been brought about by the use and instrumentality of means. In a theological point of view it matters nothing what those means have been. I agree with Mons. Guizot when he says that "Those only would be serious adversaries of the doctrine of Creation who could affirm that the universe — the earth and Man upon it — have been from all eternity, and in all respects, just what they are now."9 But this cannot be affirmed except in the teeth of facts which Science has clearly ascertained. There has been a continual coming-to-be of new Forms of Life.10 This is [282/282] Creation, no matter what have been the laws or forces employed by Creative Power.
The truth is, that the theory which fixes upon Inheritance as the cause of organic likeness, startles us only when it is applied to Forms in which unlikeness is more prominent than resemblance. The idea, for example, that the different kinds of Pigeon, or of Humming Birds, have all descended through` successive variation from some one ancestral pair, whether it be true or not, would not startle. any one. Yet, if this be true, we must be prepared for the same surmise extending farther. The advocates of Development urge that Time is a powerful factor. They say that if small changes, but constant enough, and definite enough to constitute new Species, can and do arise out of born varieties, it is impossible to fix the limits of divergence which may be reached in the course of ages. It does not follow, on the other hand, that there is no such limit because we cannot fix it. It does not necessarily follow that because we admit the idea of the Rock-dove, and the Turtle-dove, and the Ring-dove being all descended from one ancestral Pigeon, we are bound to accept the idea [282/283] of the Whale, and the Antelope, and the Monkey being all descended from some one primeval Mammal. Mr Darwin says, truly enough, that Inheritance" is that cause which alone, as far as we positively know, produces organisms quite like, or nearly like, each other." But this is no reason why we should conclude that Inheritance is the only cause which can produce Organisms quite unlike, or only very partially like, each other. We are surely not entitled to assume that all degrees and kinds of likeness can only arise from this single cause. Yet until this extreme proposition be proved, or rendered probable, we have a sound scientific basis for doubting the application of the theory precisely in proportion to the unlikeness of the animals to which it is applied.
And this is the ground of reasoning, besides the ground of feeling, on which we revolt from the doctrine as applied to Man. We do so because we are conscious of an amount and of a kind of difference between ourselves and the lower animals, which is, in sober truth, immeasurable, in spite of the close affinities of bodily structure. Yet the closeness of these affinities is a fact; and [283/284] it may with truth be said that in contrast with the gulf of separation in all resulting characters, these affinities are among the profoundest mysteries of Nature. Professor Huxley, in his work on "Man's Place in Nature," has endeavoured to prove that, so far as mere physical structure is concerned, "the differences which separate him from the Gorilla and the Chimpanzee are not so great as those which separate the Gorilla from the lower Apes." On the frontispiece of this work he exhibits in series the skeletons of the Anthropoid Apes and of Man. It is a grim and a grotesque procession. The Form which leads it, however like the others in general structural plan, is wonderfully different in those lines and shapes of Matter which have such mysterious power of expressing the characters of Mind. And significant as those differences are in the skeleton, they are as nothing to the differences which emerge in the living creatures. Huxley himself admits that these differences amount to "an enormous gulf," — to a "divergence immeasurable — practically infinite." What more striking proof could we have than this, that Organic Forms [284/285] are but as clay in the hands of the Potter, and that the"Law" of structure is entirely subordinate to the"Law" of Purpose and Intention under which the various parts of that structure are combined for use?
But Science will continue to ask, even if she never gets an answer, What is the community of physical cause which produces this community of resulting structure ? The fact which it is most difficult to disengage from the theory of Development, or, in other words, from the theory of Creation by Birth, is the existence of rudimentary or aborted organs; the existence of teeth, for example, in the jaws of the Whale — teeth which never cut the gum — and which are entirely useless to the animal. We have an inherent conviction that this must have some use in the future, — that is, in some organism to be born from this one, — or else it must have had some use in the past, — that is, in some organism from which this one has descended. In either case the power of Inheritance is suggested to the mind. We think instinctively of the existence of some Derivative Form in which these teeth have been, or are to [285/286] be, turned to use. It is only fair towards the Theory of Creation by Birth, to admit that it does explain the existence of useless organs in a sense in which no other Theory explains them. It would almost be a necessary consequence of Creation by Birth, that there must be stages in which the ultimate use of new Forms could not be yet apparent. And if mere beauty or variety were in themselves objects which Creative Power sets before itself, then, also, we might expect to meet with modifications of structure having no other apparent use. Both these explanations, however, exclude Mr Darwin's idea of Natural Selection; because this is a process which can never operate, except through the agency of actual use and disuse, upon organs already existing and capable of discharging function. The only theory of Creation by Birth which really does afford some explanation of the facts, is a theory which assumes modifications of structure to be entirely independent of the effect of actual use or disuse. Mr Darwin himself candidly admits that in flowers at least the forces of Correlated Growth do "modify important structures [286/287] independently of Utility, and therefore of Natural Selection." This admission must be extended to all organic growths. There must have been a time with all of them when they began to be; and, therefore, a time before Natural Selection had room to play. These considerations, however, only serve to put a higher interpretation on the Theory of Creation by Birth. They do not condemn it.
One suggestion, indeed, has been made on this subject which I think it is impossible to accept. When men were yet unwilling to admit the existence of life and death upon the globe so long before the creation of Man, it used to be said that fossils were only"sports of nature." So in our own day, I have heard it said that rudimentary organs are merely intended to satisfy that condition of our finite minds, in virtue of which we are unable to conceive Creation, except in connexion with some History and Method of growth. And so, as a condescension to this weakness, aborted members are given to suggest a History which was never true, and a Method which was never followed! Now, of one thing we may be sure, that there are no fictions of this kind in Nature, and [287/288] no bad jokes. Whatever natural things really point to, they point to faithfully; and the conclusions really indicated are never false. Abortive organs mean something, and they mean it truly.
Still, there is no proof that Inheritance is the only cause from which such structures can arise. In the inorganic world we know that not mere similarity, but absolute identity of form, as in crystals, is the result of laws which have nothing to do with Inheritance, but of forces whose nature it is to aggregate the particles of matter in identic shapes. It is impossible to say how far a similar unity of effect may have been impressed on the forces through which vital Organisms are first started on their way. There are some essential resemblances between all Forms of Life which it is impossible even in imagination to connect with community of blood by descent. For example, the Bilateral arrangement is common to all Organisms, down at least to the Radiata, and in this great class we have the same principle of Polarity developed in a circle. Again, the general mechanism of the digestive organs by which food is in part assimilated and part rejected, is also common through a [288/289] range of equal extent. Indeed, it may be said with truth, that never in all the changes of Time has there been any alteration throughout the whole scale of Organic Life, in the fundamental principles of chemical and mechanical adjustment, on which the great animal functions of Respiration, Circulation, and Reproduction, have been provided for.11 These are fundamental similarities of plan, depending probably on the very nature of Forces which necessitate these adjustments in order to the production of the phenomena of Life-Forces of which we know nothing, but which we have not the slightest reason to suppose are due to Inheritance. Other similarities of plan may depend on the same laws, equally unconnected with Inheritance by descent.
Inheritance, indeed, has been suggested as the cause of organic likeness, mainly because there is a difficulty in conceiving any other. But there is at least an equal difficulty in conceiving the applicability of this cause to Man. We have already seen12 that Mons. Guizot lays it down as [289/290] a physical impossibility that Man — the human pair — can have been introduced into the world except in complete stature-in the full possession of all his faculties and powers. He holds it as certain that on no other condition could Man, on his first appearance, have been able to survive and to found the human family. Even those who distrust this argument as entitled to the rank of a self-evident physical truth, must admit that it is at least quite as good as the opposite assertion, that any origin except the origin of natural birth is inconceivable. Where our ignorance is so profound, no reasoning of this kind is of much value. There is undoubtedly much to be said in support of Mons. Guizot's position. Certainly, Man as a mere animal is the most helpless of all animals. His whole frame has relation to his mind, and apart from that relation, it is feebler than the frame of any of the brutes. All its members are Correlated amongst each other with the functions of his Brain, so, that action may follow upon Knowledge — so that embodiment may be possible to Thought. Yet in its plan and [290/291] structure his frame is homologically, that is ideally, the same as the frame of the brutes-organ answering to organ, and bone to bone.
"Adherence to Type" are words expressive of an Idea, of a Purpose, which we see fulfilled in Organic Forms. But this purpose must have sought its own accomplishment by the use of means, and the question of Science always is, what were these? Love of beauty is equally a Purpose which we see fulfilled in Nature, but in the case of the Humming Birds this has been accomplished by giving to their plumes the structure of "Thin Plates," — a structure which decomposes light and flings back its prismatic colours to the eye. Fitness and special adaptation is another of the purposes of Creation, but this also is attained through the careful arrangement, and pliability to use, of physical laws. In like manner, "Adherence to Type" is the expression of a fact, or the statement of a Purpose, which, like all the other purposes fulfilled in Nature, invites to an investigation of the instrumentality employed, We see the Purpose, but we do not see the Method. We see [291/292] the purpose, for example, in the wonderful adaptability of the Vertebrate Type to the infinite varieties of Life to which it serves as an organ and a home. Science should be allowed without suspicion or remonstrance to pursue her proper object, which is to detect, if she can, what the method of this work has been. There is no point, short of the last and highest at which Science can be satisfied. Her curiosity is insatiable. It is a curiosity representing man's desire of knowledge. But that desire extends into regions where the means of investigation cease, and in which the processes of Verification are of no avail. Above and behind every Detected Method in Nature there lies the same ultimate question as before — What is it by which this is done?
It is the great mystery of our Being that we have powers impelling us to ask such questions, when we have no powers enabling us to solve them. Ideas and faint suggestions of reply are ever passing across the outer limits of the Mind, as meteors pass across the margin of the atmosphere, but which we endeavour in vain to grasp or understand. The faculties both of [292/293] reason and of imagination fall back with a sense of impotence upon some favourite phrase-some form of words built up out of the materials of analogy and conjecture. We beat against the bars in vain. The only real rest is in the confession of ignorance, and , the confession, too, that all ultimate Truth is beyond the reach of Science. It is probable that even the nearest methods of Creation, though far short of ultimate truths, lie behind a veil too thick for us to penetrate. It is here surely, if it is anywhere in the sphere of physical investigation, that the Man of Science may lay down the weapons of his analysis, and say," I do not exercise myself in great matters, or in things which are too high for me."13
There is at least one conclusion which is certain, namely, this — that no theory in respect to the means and method employed in the work of Creation — provided such theory takes in all the facts — can have the slightest effect in removing that work from the relation in which it stands to the attributes of Will. Creation by Law — [293/294] Evolution by Law — Development by Law, or, as including all those kindred ideas, the Reign of Law, is nothing but the reign of Creative Force directed by Creative Knowledge, worked under the control of Creative Power, and in fulfilment of Creative Purpose.
Last modified 10 December 2008