II.
The criticism of Positivism has taught us that there is no knowledge possible without à priori elements—that is to say, without laws inherent in thought, which impose themselves upon phenomena, so as to constitute veritable knowledge. This is the system of Kant, and thus that system avoids not only empiricism, but scepticism as well, though commonly confounded with it. For without necessary laws phenomena only form an arbitrary succession, entirely dependent upon the organization of the individual; we have no longer anything but individual sensations. In the Kantian philosophy, however, the individual is subjected to laws that are superior to himself; these are the laws of human thought, and even, perhaps, of all thought whatever. These laws impose themselves on each one of us in a necessary and universal manner, and by so doing communicate to phenomena an objective reality in this sense at least, that they are for individuals veritable objects; and thus it is that mathematical truths are objects to the intellect, even supposing they should be nowhere realized in any existence independent of thought.
But are these laws of thought anything else than laws of thought? Do they really attain to objective reality—to things in themselves. Kant has denied that they do, and our author, in following in his steps, agrees, or seems to agree, with the “Kritik” of Kant.
Let us then resolve the fundamental laws of the human intellect into five principal concepts: these are, space and time, forms of sensibility, substance and cause, laws of external experience, and, lastly, the Absolute, the final and supreme condition of all knowledge. Now, according to Kant and our author, these notions, at least the four first, are at the same time necessary as subjective conditions of thought, and contradictory so soon as we seek to realize them outside of thought.
For example, that space and time are found by implication in every internal or external representation, that they are not the result of abstraction and generalization, this has been firmly established by Kant; for the elements from which some have sought to derive them already imply them. But, at the same time, they are only internal conditions, of which the objects are unrealizable outside of ourselves, and the reason of this is given by M. Liard, as follows:—Space and time have three essential characteristics, they are homogeneous, continuous, and unlimited. Now, if we seek to make of space and time things in themselves we may doubtless conceive them as homogeneous and continuous, but not as unlimited, for no actual magnitude is unlimited; all magnitude is expressed in numbers, and numbers are necessarily finite, an infinite number involving a contradiction.
We will not enter into a question here mooted by the author, leading to what Leibnitz calls the labyrinth of the continued (Labyrinthus continui), or of invisibles; we will content ourselves with pointing out that the reason here given is not by any means in conformity with the ideas of Kant—indeed, that it contradicts them. In fact, our author here applies to the two forms of sensibility the objection that Kant raised only about real things and the sensible world. The world, indeed, being composed of parts, can only be conceived as infinite by adding these parts to each other, and by thus supposing the actual reality of an infinite number. But it is not so with space, which, not being composed of parts, is consequently not representable by numbers. “There is only one single space, there is only one single time,” says Kant. The notion of space is therefore not formed by the infinite addition of small portions of space and time. These are unities, not numbers. Hence illimitableness is given with the very intuition. “Space,” says Kant, “is represented as a given infinite magnitude,” als eine gegebene unendliche Quantität. Now, so soon as the infinite is given, instead of being made by a mental addition, it seems to us that the above difficulty vanishes.
Let us pass to the notion of substance and to that of cause. These two notions are necessary to render possible the connection of phenomena in the human mind. Our perceptions are, in fact, diverse; if they were only diverse, and had no unity, there would be no passage from one phenomenon to another; consciousness would arise and disappear with each phenomenon, to arise and die anew with the next, and so on. But then there would be no thought, for in order that thought should exist there must be at least two different things presented to the unity of consciousness. In other terms, we should be incapable of perceiving a changing thing without something that was changeless. Hence this is a necessary condition of knowledge. Now, let us see whether this condition can be rendered objective. According to our author it cannot, for if we subtract from surrounding things all the phenomena that fall under the domain of the senses, what remains? Nothing. Common-sense, indeed, believes in substance, but does not mean thereby an abstract and metaphysical entity, it means the whole of what strikes the senses; when the phenomenon is opposed to substance nothing is meant but that a new phenomenon has just added itself to preceding ones. Wood burns; here wood is the substance, combustion the phenomenon. This is how common-sense understands the matter; but if we separate from the idea of wood all that characterizes it as wood, nothing remains but a pure abstraction, of which common-sense takes no account, and has never so much as thought. Our author further combats the idea of substance by appealing to the metaphysical difficulties that it suggests. Is there only one substance, or are there several? Either hypothesis is equally difficult to sustain. In other words, substance is nothing more than that law in virtue of which the mind connects phenomena in one and the same act of thought.
Here, again, we are obliged to say that the preceding arguments against the objectivity of the notion of substance are, in our opinion, far from conclusive. In the first place, it seems to us a false philosophical method to exclude an object from the human mind because it suggests difficulties that we are incapable of solving. Every object must be presented to us as existing before we can judge of the possibility of that object. Perhaps we do not possess the means of solving all the questions which the existence of an object may suggest, but this is no reason why it should not exist. The existence of things cannot be subordinated to the limits of our understanding; it is this very principle which seems to us soundest of all in the “Kritik” of Kant. Even should we be for ever incapable of knowing whether there is one substance or whether there are many, even should we be for ever doomed to doubt as to this point, it would not follow that the existence of one or of many substances were thereby done away with. Moreover, the criticism of our author goes much further than the imperilling the objectivity of substance; it really bears against the very notion itself. If, in fact, every phenomenon being withdrawn, nothing remains any longer in my mind, it is not merely objective substance that vanishes, it is the notion itself. What, indeed, is a notion which, analyzed, comes to naught? And what is this necessary law which is a nonentity? Our author tells us that if we remove all the accidents there remains “nothing perceptible to the senses.” This is mere tautology, for it is too evident that nothing sensible ought to remain in the notion, all sensible accidents having been withdrawn; but what does remain is that without which phenomena could not be connected. And this is no empty concept, for how should an empty concept have any uniting power? And, lastly, when the author, correcting himself, as we think, says that the notion of substance reduces itself to what he calls a “fundamental phenomenon,” he does nothing but change the word, and in reality reverts to what we call substance. For in what sense does anything fundamental—that is to say, that to which other phenomena ultimately reduce themselves, and which cannot be reduced to any other—still preserve the name of phenomenon? All this, therefore, is but admitting under one name what has been denied under another.
The criticism of the notion of cause is quite similar to that of the notion of substance. It is a notion necessary to the mind, for just as without substance there can be no mental connection between simultaneous phenomena, in the same way without cause there can be no connection between successive phenomena. Causality is the necessary law that connects each phenomenon with its anterior conditions. Without this law there could be no science, no induction, no experience. It cannot, consequently, be derived from experience, since it is the very condition of it. But do we seek to render cause objective as well as substance? If so, we must understand it in a different sense. Cause is no longer merely a phenomenon anterior to another, the antecedent of a consequent. It is something quite different, it is force, the active power, that initiates the movement, and of which we find the type in our own consciousness. Hence, to render cause objective is nothing less than to spiritualize the universe, to suppose everywhere causes similar to ours—it is a kind of universal Fetichism. And, further, we fall into the same difficulties as we did with regard to substance. Is there only one cause or many causes? Lastly, causation thus understood is of no use whatever to science, for science has no need at all of metaphysical forces, that which is necessary to science, and employed by it under the name of force, being a measurable quantity which it disengages from phenomena and from experience.
On this new ground the difficulty that confronts critical idealism is the same as that affecting the notion of substance. It lies in defending the position against empiricism, from which are borrowed all the arguments against the reality of the cause, while attempting, nevertheless, to preserve the notion of it. How succeed in retaining as an à priori law what empiricism declares to be only an acquired habit? How explain a law of mind imposing a determined order on external phenomena? How can the entirely subjective need of relation determine phenomena to produce themselves in the order desired by our intelligence? The thunder rolls: my mind, in virtue of an innate law, insists on this phenomenon being connected with a certain totality of antecedent phenomena—namely, heat, the formation of clouds charged with electricity of different kinds, the meeting of these clouds, and the combination of the two electricities, &c. How and why have these phenomena produced themselves in order to satisfy my mind? Our author somewhere reproaches the partisans of innate ideas with supposing ideas on one side and phenomena on the other. How can he exonerate Kant’s system from this objection? No philosopher ever insisted more than he on the opposition between matter and form, the former being, as he says, “given à posteriori,” the latter ready prepared à priori in the mind. No philosopher, not even Leibnitz, has more radically separated sensibility which is passive from the understanding whose principle is spontaneity. How do these two opposite principles happen to agree? Even were it pointed out that our senses themselves are innate, since our sensations are but the manifestation of the specific activity of each one of them—light, of the optic nerve, sound, of the acoustic—it still remains certain that our sensations are only subjective as regards their content and not as regards their origin; they arise in virtue of causes to us unknown. How should understanding, by aid of a purely mental law, and in order to its own satisfaction, evoke sensible phenomena from nothingness, and if it had such a power, it could only be in virtue of an active force, that is, of a veritable causality? You say that you require relation, without which there could be no knowledge. And why must there be knowledge because you feel the need of it? And why should there not be in the understanding a need of unity and relation that sensibility does not satisfy? To say that the mind at the same time that it thinks the law produces phenomena conformable to that law, is to make the mind itself the cause in the objective and metaphysical sense of the word—is no other than that universal spiritualism that the author began by refuting. We are therefore very far from admitting his criticism of the principles of causality. Let us go on to the notion of the absolute.
M. Liard begins very properly by pointing out the confusion too often made between the notion of the infinite and that of the absolute. He says that the infinite can only be strictly understood in the mathematical sense, but that hence, as Leibnitz has said, the true infinite is the absolute. He admits the existence in the mind of the notion of the absolute in so far as it is inseparable from that of the relative. The Scotch philosopher, Hamilton, had endeavoured to suppress this notion, and had reproached Kant for not having completely exorcised the phantom of the absolute,[2] and for having retained it in the character of idea while contesting its objective existence. It is remarkable that on this point, so decisive for metaphysics, Hamilton should have been opposed and refuted by the more modern English philosophers, who often pass for having pushed the critical and negative spirit further than he, when, indeed, on this point it is just the contrary. Herbert Spencer especially is one whom it is interesting to consult here. He maintains against Hamilton the notion of the absolute as positive, not negative, “as the correlative notion of the relative, as the substratum of all thoughts”—I quote verbally—“as the most important element of our knowledge.”[3] He also maintains in opposition to Hamilton that the affirmation of the absolute is “a knowledge and not a belief.” Only according to him this object that underlies all our thoughts is absolutely indeterminable by us. We know that it is, not what it is. It is the incomprehensible, the unknowable.
M. Liard seems to us substantially to admit all these conclusions. “Existence by others,” he says, “is not to be understood without self-existence.” “Without the spur of the notion of the absolute, how comprehend the obstinate persistence of the human mind in transcending the limits of the relative? Is not this a proof that the relative is not sufficient to itself?” It is one thing to affirm the absolute, another to determine its nature. Even granting that we be powerless to speak as to the essence of the absolute, and that it can never be for us other than the indeterminable and unknowable, “is it nothing to be assured of the existence of an unknowable? At all events religious beliefs might in default of scientific certainty find in an irremovable basis this conviction.”
We see therefore that our author agrees with Mr. Herbert Spencer in granting the existence of the absolute; he does not seem to reduce it, as Kant does, to a mere idea. He confines himself to saying that it cannot be determined. He shows that none of the notions that have been previously examined can fill up the concept of the absolute. Neither space, nor time, nor substance, nor cause, nor the totality of phenomena, can be raised to the notion of absolute. It is therefore indeterminable. Now, as the absolute is the proper object of metaphysics, it follows that metaphysics lack an object, having nothing to say thereon. Hence it is self-condemned, and consequently metaphysics is not a science.
Such is the conclusion of the second part. The first appeared to raise us above phenomena by establishing the necessity of thought and of its fundamental law. But the second confines us within the domains of thought, and forbids us to go beyond. There is, indeed, a science of thought, but this science is criticism, not metaphysics. Have we, then, only escaped from positivism to fall into the abyss of scepticism?
Before explaining in what manner the author has endeavoured to escape from this abyss, there is room for an important remark on the previous discussion as to the notion of the absolute. Scepticism on this point may assume three forms. Either, first, we do not even possess the notion of it, our notion is entirely negative,—the absolute is the non-relative, is indeed the relative with a negation: such is the view of Sir W. Hamilton. Or else, secondly, we have the notion of the absolute, of being in itself and by itself, of the superlatively real being, ens realissimum, as Kant expresses it, but it is only a notion, we cannot affirm the existence: this is Kant’s doctrine. Or, thirdly, we have indeed a positive notion of the absolute, and we necessarily affirm its existence, only we are unable to determine its nature: this is the conclusion arrived at by Herbert Spencer. Now, of these three doctrines the two first alone, in our opinion, belong to what may be called criticism. The third is manifestly a return to dogmatism. The more or less of determination in the notion of the absolute is only the second problem of metaphysic; the first is the existence of that absolute. And, moreover, the doctrine of the divine incomprehensibility has always been maintained by the greatest metaphysicians as well as the greatest theologians. All mystics incline to it. There may therefore be room for debate as to the more or less approximative character of our concepts of the absolute. That any of these are adequate, or absolutely adequate, is what no philosopher has ever thought himself obliged to maintain. No doubt, to define the absolute as the unknowable, is to express the doctrine under a very rigorous form, but one could hardly refuse to allow the absolute to be the incomprehensible.
Consequently, then, if the author, as appears to be the case from the passages we have quoted, thinks with Mr. Herbert Spencer that the notion of the absolute corresponds to an existence, and if he contents himself with maintaining its indeterminability, we may, if we like, consider this to be a singularly attenuated metaphysic, but we are not entitled to deny that it amounts to a departure from criticism and a return to metaphysic. If, on the other hand, criticism does at least suppose one fundamental datum,—thought, namely, and with the thought the thinking,—we are still forced to grant to Descartes, and consequently to metaphysic, the existence of the thinking subject; and hence that science which our author declares not to be one would be found already in possession of the claim by the single fact of what he has called the criticism of two fundamental postulates: I think, I am—I think the absolute, the absolute is. And is this then nothing?
We are therefore of opinion that M. Liard ought to have concluded the second part of his work as he did the first—that is to say, that he ought to have shown the insufficiency of criticism as he did that of positivism. To our mind, criticism supposes metaphysic, as positivism supposes criticism. Metaphysic contains the reason of criticism, as criticism does that of positivism. Instead, then, of saying that metaphysic is not a science, we should rather call it the culminating point of science. But in place of following this natural order, which is, indeed, only his own method, our author has preferred to prove criticism right in the second part of his book, and metaphysic right in the third, by a sort of saltus, not contained in what goes before. He has chosen to appear nearer to Kant than he really is; has chosen to carry on his own evolution in Kant’s manner, and to rebuild on different bases what he had demolished; but we shall see that this evolution is in reality quite different from that of Kant, and that his justification of criticism is only apparent, or at least if he defends it, this is really only in order subsequently to undermine it.