On the Philosophy of Discovery, Chapters Historical and Critical

I do not shrink from saying, therefore, that the Idea of Space which is a constituent of the human mind existing in the universe is, as far as it goes, identical with the Idea of Space which is a constituent of the universe. And this I give as the answer to the question, How it is that the necessary truths of Geometry universally coincide with the relations of the phenomena of the universe? And this doctrine, it is to be remembered, carries us to the further doctrine, that the Idea of Space in the human mind is, so far as it goes, coincident with the Idea of Space in the Divine Mind.

13. (Idea of Time.)—What I have said of the Idea of Space, may be repeated, for the most part, with regard to the Idea of Time; except that the Idea of Time, as such, does not give rise to a large collection of necessary truths, such as the propositions of Geometry. Some philosophers regard Number as a modification or derivative of the Idea of Time. If we accept this view, we have, in the Science of Arithmetic, a body of necessary truths which flow from the Idea of Time. But this doctrine, whichever way held, does not bear much on the question with which we are now concerned. That which we do hold is, that the Idea of Time in the human mind is, so far as it goes, coincident with the Idea of Time in the Divine Mind: and that this is the reason why the events of the universe, as contemplated by us, conform to necessary laws of succession: while at the same time we must suppose that all the perplexities in the Idea of Time which embarrass the human mind—the perplexities, for instance, which arise from contemplating a past and a future eternity, are, in the Divine Mind, extinguished in the Light of the Idea itself.

Space and Time have, and have generally been regarded as having, peculiar prerogatives in our speculations concerning the constitution of the universe. We see and perceive all things as subject to the laws of Space and Time; or rather (for the term Law does not here satisfy us), as being and happening in space and in time: and probably most persons will have no repugnance to the doctrine that the Divine Mind, as well as the human, so regards them, and has so constituted them and us that they must be so regarded. Space and Time are human Ideas which include all objects and events, and are the foundation of all human Science. And we can conceive that Space and Time are also Divine Ideas which the Divine Mind causes to include all objects and events, and makes to be the foundation of all existence. So far as these Ideas go, our doctrine is not difficult or new.

14. (Ideas of Force and Matter.)—But what are we to say of the Ideas which come next in the survey of the sciences, Force and Matter? These are human Ideas—the foundations of several sciences—of the mechanical sciences in particular. But are they the foundations of necessary truths? Have we necessary truths respecting Force and Matter? We have endeavoured to prove that we have:—that certain fundamental propositions in the Science of Mechanics, although, historically speaking, they were discovered by observation and experience, are yet, philosophically speaking, necessary propositions. And being such, the facts of the universe must needs conform to these propositions; and the reason why they do so, we hold, in this as in the former case, to be, that these Ideas, Force and Matter, are Ideas in the Divine Mind:—Ideas according to which the universe is, by the Divine Cause, constituted and established.

15. That Force and Matter are Ideas existing in the Divine Mind, and coincident with the Idea of Force and Matter in the human mind, as far as these go, is a doctrine which is important in our view of the universe in relation to its Cause and Foundation.

These are very comprehensive and fundamental Ideas, and there are certain universal relations among external things which rest upon these Ideas. The two, Force and Matter, are, in a certain way, the necessary antithesis and opposite condition each of the other. Force (that is Mechanical Force, Pressure or Impulse) cannot act without matter to act upon. Matter (that is Body) cannot exist without Force by which it is kept in its place, by which its parts are held together, and by which it excludes every other body from the place which it occupies. We cannot conceive Force without Matter, or Matter without Force; the two are, as Action and Reaction, necessarily co-ordinate and coexistent. In every part of the universe they must be so. In every part of the universe, if there be material objects, there must be Force; if there be Force, there must be material objects.

Our apprehension of this universal necessity arises from our having the Ideas of Force and Matter which are human Ideas. The actuality of this universal antithesis arises from the Ideas of Force and Matter being Ideas in the Divine Mind;—Ideas realized as a part of the fundamental constitution of the universe.

That Force and Matter are thus among the Ideas in the Divine Mind, and that, with them, the Ideas of Force and Matter in the human mind, regarded in their most general form, agree so far as they go, is another step in the doctrine which I am trying to unfold. That the Ideas of Force and Matter in the Divine Mind are such as to banish by their own light, innumerable contradictions and perplexities which darken these Ideas in the human mind, is to be supposed: and thus the Divine Mind is infinitely luminous and comprehensive compared with the human mind.

16. (Creation of Matter.)—It may perhaps be urged, as an objection to this doctrine, that it asserts Matter to be a necessary constituent of the universe, and thus involves the assertion of the eternity of Matter. But in reality the doctrine asserts Matter to be eternal, only in the way in which time and space are eternal. Whether we hold that there was a creation before which time and space did not exist,—with the poet who says

Ere Time and Space were Time and Space were not,—

is not essential to our present inquiry. Certainly we cannot conceive such a state, and therefore cannot reason about it. We have no occasion here to speak of Creation, nor have spoken of it. What I have said is, that Space and Time, Force and Matter are universal elements, principles, constituents, of the universe as it is—and necessary Ideas of the human mind existing in that universe. If there ever was a Creation before which Matter did not exist, it was a Creation before which Force did not exist. And in the universe as it is, the two are necessarily co-existent in the human thought because they are co-existent in the Divine Thought which makes the world.

We apply then to Force and Matter the doctrine—the Platonic doctrine, if any one please so to call it,—that the world is constituted according to the Ideas of the Divine Mind, and that the human mind apprehends the inward and most fundamental relations of the universe by sharing in some measure of those same Ideas.

17. (Platonic Ideas.)—But do we go on with Plato to extend this doctrine of Ideas to all the objects and all the aspects of objects which constitute the material universe? Do we say with Plato that there is not only an Idea of a Triangle by conformity to which a figure is a triangle, but an Idea of Gold, by conformity to which a thing is gold, and Idea of a Table, by conformity to which a thing is a table?

We say none of these things. We say nothing which at all approaches to them. We do not say that there is an Idea of a Triangle, the archetype of all triangles; we only say that man has an Idea of Space, which is an Idea of a fundamental reality; and that therefore from this Idea flow real and universal truths—about triangles and other figures. Still less do we say that we have an archetypal Idea of Gold, or of a Metal in general, or of any of the kinds of objects which exist in the world. Here we part company with Plato altogether.

But have we any Ideas at all with regard to objects which we thus speak of as separable into Kinds? We can have knowledge,—even exact and general knowledge, that is, science—with regard to such things—with regard to plants and metals—gold and iron. Do we possess in our minds, with regard to those objects, any Ideas, any universal principles, such as we possess with regard to geometrical figures or mechanical actions? And if so, are those human Ideas verified in the universe, as the Ideas hitherto considered are? and do they thus afford us further examples of Ideas in the human mind which are also Ideas in the Divine Mind, manifested in the constitution of the universe?

18. (Idea of Kinds.)—We answer Yes to these questions, on this ground:—the objects that exist in the world, plants and metals, gold and iron, for example, in order that they may be objects with regard to which we can have any knowledge, must be objects of distinct and definite thought. Plant must differ from metal, gold from iron, in order that we may know anything at all about any of these objects. The differences by which such objects differ need not necessarily be expressed by definitions, as the difference of a triangle and a square are expressed; but there must manifestly be fixed and definite differences, in order that we may have any knowledge about them. These Kinds of things must be so far distinct and definite, as to be objects of distinct and definite thought. The Kinds of natural objects must differ, and we must think of things as of different Kinds, in order that we may know anything about natural objects. Living in a world in which we exercise our Intellect upon the natural objects which surround us, we must regard them as distinct from each other in Kind. We must have an Idea of Kinds of natural objects.

19. The Idea of a Kind involves this principle: That where the Kind differs the Properties may differ, but so far as the Kind is the same the Properties contemplated in framing the notion of each Kind are the same. Gold cannot have the distinctive properties of Iron without being Iron.

In the case of human knowledge, each Kind is marked by a word—a name; and the doctrine that the notion of the Kind must be so applied that this same Kind of object shall have the same properties, has been otherwise expressed by saying that Names must be so applied that general propositions may be possible. We must so apply the name of Gold that we may be able to say, gold has a specific gravity of a certain amount and is ductile in a certain degree.

20. But this condition of the names of Kinds,—that they must be such that general propositions about these Kinds of objects shall be possible;—is it a necessary result of the Idea of Kind? And if so, can the Idea of Kind, thus implying the use of language, and a condition depending on the use of language, be an Idea in the Divine as well as in the human mind? Can it be, in this respect, like the Ideas which we have already considered, Space and Time, Force and Matter?

We cannot suppose that the Ideas which exist in the Divine Mind imply, in the Supreme Intelligence, the need of language, like human language. But there is no incongruity in supposing that they imply that which we take as the condition of such language as we speak of, namely, distinct thought. There is nothing incongruous in supposing that the Supreme Intelligence regards the objects which exist in the universe as distinct in Kind: and that the Idea of Kind in the human mind agrees with the Idea of Kind in the Divine Mind, as far as it goes. And as we have seen, the Idea of Properties is correlative and coexistent with the Idea of Kind, so that the one changing, the other changes also. There is nothing incongruous in supposing that the Divine Mind manifests in the universe of which it is the Cause and Foundation, these two, its co-ordinate Ideas: and that the human mind sees that these two Ideas are co-ordinate and coexistent, in virtue of its participating in these Ideas of the Divine Mind. The universe is full of things which man perceives do and must differ correspondingly in kind and in properties; and this is so, because the Ideas of various Kinds and various Properties are part of the scheme of the universe in the Divine Mind.

21. That the Ideas of Kinds and Properties as coordinate and interdependent, though common, to a certain extent, to the human and the Divine Mind, are immeasurably more luminous, penetrating and comprehensive in the Divine than in the human mind, is abundantly evident. In fact, though man assents to such axioms as these,—that the Properties of Things depend upon their Kinds, and that the Kinds of Things are determined by their Properties,—yet the nature of connexion of Kinds and Properties is a matter in which man's mind is all but wholly dark, and on which the Divine Mind must be perfectly clear. For in how few cases—if indeed in any one—can we know what is the essence of any Kind;—what is the real nature of the connexion between the character of the Kind and its Properties! Yet on this point we must suppose that the Divine Intellect, which is the foundation of the world, is perfectly clear. Every Kind of thing, every genus and species of object, appears to Him in its essential character, and its properties follow as necessary consequences. He sees the essences of things through all time and through all space; while we, slowly and painfully, by observation and experiment, which we cannot idealize or can idealize only in the most fragmentary manner, make out a few of the properties of each Kind of thing. Our Science here is but a drop in the ocean of that truth, which is known to the Divine Mind but kept back from us; but still, that we can know and do know anything, arises from our taking hold of that principle, human as well as Divine, that there are differences of Kinds of things, and corresponding differences of their properties.

22. (Idea of Substance.)—I shall not attempt to enumerate all the Ideas which, being thus a part of the foundation of Science in the human mind and of Existence in the universe, are shown to be at the same time Ideas in the Divine and in the human mind. But there is one other of which the necessary and universal application is so uncontested, that it may well serve further to exemplify our doctrine. In all reasonings concerning the composition and resolution of the elements of bodies, it is assumed that the quantity of matter cannot be increased or diminished by anything which we can do to them. We have an Idea of Substance, as something which may have its qualities altered by our operations upon it, but cannot have its quantity changed. And this Idea of Substance is universally verified in the facts of observation and experiment. Indeed it cannot fail to be so; for it regulates and determines the way in which we interpret the facts of observation and experiment. It authorized the philosopher who was asked the weight of a column of smoke to reply, "Subtract the weight of the ashes from that of the fuel, and you have the weight of the smoke:" for in virtue of that idea we assume that, in combustion, or in any other operation, all the substance which is subjected to the operation must exist in the result in some form or other. Now why may we reasonably make this assumption, and thus, as it were, prescribe laws to the universe? Our reply is, Because Substance is one of the Ideas according to which the universe is constituted. The material things which make up the universe are substance according to this Idea. They are substance according to this Idea in the Divine Mind, and they are substance according to this Idea in the human mind, because the human mind has this Idea, to a certain extent, in common with the Divine Mind. In this, as in the other cases, the Idea must be immeasurably more clear and comprehensive in the Divine Mind than in the human. The human Idea of substance is full of difficulty and perplexity: as for instance; how a substance can assume successively a solid, fluid and airy form; how two substances can be combined so as entirely to penetrate one another and have new qualities: and the like. All these perplexities and difficulties we must suppose to vanish in the Divine Idea of Substance. But still there remains in the human, as in the Divine Idea, the source and root of the universal truth, that though substances may be combined or separated or changed in form in the processes of nature or of art, no portion of substance can come into being or cease to be.

23. (Idea of Final Cause.)—There is yet one other Idea which I shall mention, though it is one about which difficulties have been raised, since the consideration of such difficulties may be instructive: the Idea of a purpose, or as it is often termed, a Final Cause, in organized bodies. It has been held, and rightly318, that the assumption of a Final Cause of each part of animals and plants is as inevitable as the assumption of an efficient cause of every event. The maxim, that in organized bodies nothing is in vain, is as necessarily true as the maxim that nothing happens by chance. I have elsewhere319 shown fully that this Idea is not deduced from any special facts, but is assumed as a law governing all facts in organic nature, directing the researches and interpreting the observations of physiologists. I have also remarked that it is not at variance with that other law, that plants and that animals are constructed upon general plans, of which plans, it may be, we do not see the necessity, though we see how wide is their generality. This Idea of a purpose,—of a Final Cause,—then, thus supplied by our minds, is found to be applicable throughout the organic world. It is in virtue of this Idea that we conceive animals and plants as subject to disease; for disease takes place when the parts do not fully answer their purpose; when they do not do what they ought to do. How is it then that we thus find an Idea which is supplied by our own minds, but which is exemplified in every part of the organic world? Here perhaps the answer will be readily allowed. It is because this Idea is an Idea of the Divine Mind. There is a Final Cause in the constitution of these parts of the universe, and therefore we can interpret them by means of the Idea of Final Cause. We can see a purpose, because there is a purpose. Is it too presumptuous to suppose that we can thus enter into the Ends and Purposes of the Divine Mind? We willingly grant and declare that it would be presumptuous to suppose that we can enter into them to any but a very small degree. They doubtless go immeasurably beyond our mode of understanding or conceiving them. But to a certain extent we can go. We can go so far as to see that they are Ends and Purposes. It is not a vain presumption in us to suppose that we know that the eye was made for seeing and the ear for hearing. In this the most pious of men see nothing impious: the most cautious philosophers see nothing rash. And that we can see thus far into the designs of the Divine Mind, arises, we hold, from this:—that we have an Idea of Design and of Purpose which, so far as it is merely that, is true; and so far, is Design and Purpose in the same sense in the one case and in the other.

I am very far from having exhausted the list of Fundamental Ideas which the human mind possesses and which have been made the foundations of Sciences. Of all such Ideas, I might go on to remark, that they are of universal validity and application in the region of external Facts. In all the cases I might go on to inquire, How is it that man's Ideas, developed in his internal world, are found to coincide universally with the laws of the external world? By what necessity, on what ground does this happen? And in all cases I should have had to reply, that this happens, and must happen, because these Ideas of the human mind are also Ideas of the Divine Mind according to which the universe is constituted. Man has these thoughts, and sees them verified in the universe, because God had these thoughts and exemplifies them in the universe.

24. (Human immeasurably inferior to Divine).—But of all these Ideas, I should also have to remark, that the way in which man possesses them is immeasurably obscure and limited in comparison with the way in which God must be supposed to possess them. These human Ideas, though clear and real as far as they go, in every case run into obscurity and perplexity, from which the Ideas of the Divine Mind must be supposed to be free. In every case, man, by following the train of thought involved in each Idea, runs into confusion and seeming contradictions. It may be that by thinking more and more, and by more and more studying the universe, he may remove some of this confusion and solve some of these contradictions. But when he has done in this way all that he can, an immeasurable region of confusion and contradiction will still remain; nor can he ever hope to advance very far, in dispelling the darkness which hangs over the greater part of the universe. His knowledge, his science, his Ideas, extend only so far as he can keep his footing in the shallow waters which lie on the shore of the vast ocean of unfathomable truth.

25. But further, we have not, even so, exhausted our estimate of the immeasurable distance between the human mind and the Divine Mind:—very far from it: we have only spoken of the smallest portion of the region of truth,—that about which we have Sciences and Scientific Ideas. In that region alone do we claim for man the possession of Ideas the clearness of which has in it something divine. But how narrow is the province of Science compared with the whole domain of human thought! We may enumerate the sciences of which we have been speaking, and which involve such Ideas as I have mentioned. How many are they? Geometry, Arithmetic, Chemistry, Classification, Physiology. To these we might have added a few others; as the sciences which deal with Light, Heat, Polarities; Geology and the other Palætiological Sciences; and there our enumeration at present must stop. For we can hardly as yet claim to have Sciences, in the rigorous sense in which we use the term, about the Vital Powers of man, his Mental Powers, his historical attributes, as Language, Society, Arts, Law, and the like. On these subjects few philosophers will pretend to exhibit to us Ideas of universal validity, prevailing through all the range of observation. Yet all these things proceed according to Ideas in the Divine Mind by which the universe, and by which man, is constituted. In such provinces of knowledge, at least, we have no difficulty in seeing or allowing how blind man is with regard to their fundamental and constituent principles; how weak his reason; how limited his view. If on some of the plainest portions of possible knowledge, man have Ideas which may be regarded as coincident to a certain extent with those by which the universe is really constituted; still on by far the largest portion of the things which most concern him, he has no knowledge but that which he derives from experience, and which he cannot put in so general a form as to have any pretensions to rest it upon a foundation of connate Ideas.

26. (Science advances towards the Divine Ideas.)—But there is yet one remark tending somewhat in the opposite direction, which I must make, as a part of the view which I wish to present. Science, in the rigorous sense of the term, involves, we have said, Ideas which to a certain extent agree with the Ideas of the Divine Mind. But science in that sense is progressive; new sciences are formed and old sciences extended. Hence it follows that the Ideas which man has, and which agree with the Ideas of the Divine Mind, may receive additions to their number from time to time. This may seem a bold assertion; yet this is what, with due restriction, we conceive to be true. Such Ideas as we have spoken of receive additions, in respect of their manifestation and development. The Ideas, the germ of them at least, were in the human mind before; but by the progress of scientific thought they are unfolded into clearness and distinctness. That this takes place with regard to scientific Ideas, the history of science abundantly shows. The Ideas of Space and Time indeed, were clear and distinct from the first, and accordingly the Sciences of Geometry and Arithmetic have existed from the earliest times of man's intellectual history. But the Ideas upon which the Science of Mechanics depends, having been obscure in the ancient world, are become clear in modern times. The Ideas of Composition and Resolution have only in recent centuries become so clear as to be the basis of a definite science. The Idea of Substance indeed was always assumed, though vaguely applied by the ancients; and the Idea of a Design or End in vital structures is at least as old as Socrates. But the Idea of Polarities was never put forth in a distinct form till quite recently; and the Idea of Successive Causation, as applied in Geology and in the other Palætiological Sciences, was never scientifically applied till modern times: and without attempting to prove the point by enumeration, it will hardly be doubted that many Scientific Ideas are clear and distinct among modern men of science which were not so in the ancient days.