Negative Ontology
——A Critical Appraisal of Kant’s Ontological Thought
Abstract: This essay aims to interpret Kant’s ontological thought in Critique of Pure Reason and Introduction to a Future Metaphysics. Kant’s ontology differs radically from the tradition; it is what may be called a “negative ontology,” that is, an ontology whose aim is not to expand knowledge, but to set limits to it. The thing-in-itself is precisely Kant’s ontic ground; Kant emphasizes that the thing-in-itself is unknowable, yet must be thinkable and acknowledged. The positing of the thing-in-itself, on the one hand, restricts the arrogance of dogmatism; on the other hand, it also restrains the lawlessness of skeptics. In the realm of thought, Kant strives to seek a new order between “despotism” and “anarchy,” namely a free, democratic order governed by law. Negative ontology does not hinder the freedom of science, and at the same time prevents science from encroaching upon the domains of morality and faith. Yet these efforts, as the basic background and precondition of Kant’s philosophical system, have not received sufficient attention from Kant’s successors in the history of philosophy.
Keywords: negative ontology thing-in-itself critical philosophy
The Thing-in-Itself Is Unknowable
The Thing-in-Itself as Negative Ontic Ground
Grounding Means Setting Limits
Unlike the question “How is knowledge possible?”, as the overall question of Introduction to a Future Metaphysics, Kant asks: “Is metaphysics possible anywhere?[271][①]” This is because, for Kant, the fact that human beings do in fact possess certain knowledge is beyond doubt; the question is only to inquire into the source of that knowledge. Whether human beings truly possess a genuine metaphysics, however, is highly questionable.
Kant believed that traditional metaphysicians had all fallen into dogmatism: without first critically examining and scrutinizing their own capacities, they overstepped the bounds of understanding and built one magnificent yet illusory palace after another on the sand.
And by Kant’s time this rootless, uncritical metaphysical tradition had already fallen into difficulty—not so much that traditional metaphysics disintegrated under Kant’s criticism, as that Kant was committed to rescuing metaphysics from its predicament. This predicament, in a sense, accompanied the flourishing of science: metaphysics, once called “the queen of all sciences,” became, in an age of scientific prosperity, instead an old woman driven out and abandoned. Kant vividly paraphrases the predicament of metaphysics with Hecuba’s words in Ovid’s Metamorphoses: “Not long ago I was first of all things, ruling the world by virtue of my many offspring; now I am exiled, possessing nothing.” (AIX) Kant likens the metaphysics of the traditional dogmatists to “despotic rule”; because its legislation is primitive and barbaric, metaphysical governance will degenerate into anarchy amid civil war and come under attack from skeptics—those “nomads” who seek to tear everything down. Kant’s wish, then, is to rescue human reason from this lawless condition of chaos, to “legislate” for reason, and to replace dogmatism, which rules by force and authority, with this “court” of the critique of pure reason, thereby re-establishing a foundation and order for knowledge.
A court under democracy is distinct both from anarchy and from a despot.
Kant believed that although despotism ought to be overthrown, anarchism is even more undesirable. Kant never doubted the necessity of metaphysical inquiry; he thought that human beings could not truly free themselves from metaphysics, which is a natural endowment of human beings:
“To pretend to be indifferent with respect to such investigations is futile, for their object cannot be indifferent to human nature. Those affectedly indifferent people, however much they may try to make themselves unrecognizable by changing academic language into a popular tone, will, wherever they think something at all, inevitably arrive at those metaphysical propositions which they profess to despise so much.”[AX]
“If one day the human mind were to completely abandon metaphysical investigations, that would be as undesirable as if, in order not always to breathe impure air, we were simply to stop breathing altogether. Therefore there will always be metaphysics in the world. More than that, every person, especially every thinking person, will have metaphysics. In the absence of any public standard, each will shape metaphysics in his own way. Now, what has hitherto been called metaphysics does not satisfy any reflective person, but a complete abandonment of it is also impossible. Therefore one must eventually attempt a critique of pure reason itself; or, if a critique already exists, one must study and thoroughly examine it, because there is no other way to satisfy this pressing need, which is greater than mere curiosity.”[367]
Kant hoped to establish a new order, not by building a new despotism, but by constructing a lawful society founded on the ideals of freedom and democracy.
Unlike a despot, the court on the one hand judges according to universal laws rather than arbitrary decrees; on the other hand, by restricting lawbreakers it maintains order. In other words, the functions of the court and the police are both “negative”: they do not produce or create anything for society as a whole. Yet this negative force is necessary; without them, society would descend into chaos, and people would in fact not gain freedom but lose it.
Kant thought that the usefulness of his critical philosophy was to “never risk going beyond the bounds of experience by means of speculative reason” [BXXIV], and thus after all it is negative. Yet “because it thereby at the same time removes obstacles that could otherwise entirely eliminate or even restrict the practical use of reason, it does in fact have positive and very important utility.”[BXXV] “To deny that this service of critique has positive utility is like saying that the police produce no positive utility.”[BXXV] In simple terms, Kant’s Critique of Pure Reason aims to set limits for reason, and setting limits for reason is precisely to ensure the freer use of reason, especially to leave room for practical reason.
This essay seeks precisely to offer a brief appraisal of this “negative” aspect of Kant’s critical philosophy.
How Is Knowledge Possible
“How is knowledge possible?” is the principal problem confronting Kant’s metaphysics. As to the fact that human beings do indeed possess knowledge of mathematics and natural science, Kant never doubted it. Kant understood that, so far as natural science itself has already developed such rich achievements, there is no need to establish a metaphysical foundation in advance. However, if we do not at all examine and reflect on the source of knowledge, then people are bound to extend the use of understanding blindly, thereby arrogantly applying, to the domains of morality and faith, methods that have succeeded in the realm of natural science; and this is dangerous. Therefore, Kant’s commitment to inquiring into “how knowledge is possible” is not an attempt to provide any positive contribution to the expansion of knowledge, but always a hope of exerting influence through negative means.
Before inquiring into the source of knowledge, Kant had already achieved a very deep grasp of the natural science of his time; many scientific essays written in the pre-critical period attest to Kant’s solid scientific training.
Kant incisively identified the key to the success of modern science—“the experimental method”—namely, the transformation of the role of human reason before nature: from a mere observer or listener into an examiner and legislator. This is precisely the essence of what is called the “experimental method.” Experiment is not merely observation; rather, it is “to seek in nature what reason itself has put into nature…”[BXIV]
“…A light dawned in the hearts of all investigators of nature. They came to understand that reason has insight only into what it itself produces according to its own rules; that it must go before with principles of its own judgment according to unchanging laws, forcing nature to answer its questions, and must not let itself be led about, as it were, by nature alone with a nose-ring; for otherwise contingent observations, made without any previously devised plan, would not be connected in a necessary law that reason seeks and requires. Reason must, with one hand, hold its principles, according to which alone coherent appearances can count as laws, and with the other hand lead experiments, which it has devised in accordance with those principles, toward nature, indeed in order to be taught by nature, but not in the character of a pupil who recites everything the teacher wishes to hear, rather in that of an appointed judge who compels witnesses to answer the questions he puts to them.”[BXIII]
That is to say, the resemblance between modern science’s “Copernican revolution” and Kant’s “Copernican revolution” in epistemology is not merely metaphorical; in fact, the key to the success of the modern scientific revolution lies precisely in what Kant calls “human reason legislates for nature.” Only, scientists and philosophers of the past had not deeply understood this point and its philosophical significance. Kant was committed to reconstructing metaphysics, but did not wish to provide a new methodology for natural science; rather, he tried to borrow this highly successful scientific method to establish a metaphysics as science.
Kant said: “Until now it has been assumed that all our knowledge must conform to objects; but all attempts to discover something about objects a priori through concepts, in order to extend our knowledge, have, under this assumption, come to nothing. Therefore one may try whether we do not make better progress in the tasks of metaphysics by assuming that objects must conform to our cognition.”[BXVI] Kant believed that his Critique was precisely a successful attempt at this new method.
Empiricism is the starting point of transcendental philosophy. Like empiricists, Kant repeatedly emphasized: “That all our knowledge begins with experience there can be no doubt, … in time, therefore, no knowledge in us precedes experience, and all knowledge begins with it.”[B1] Yet Kant pointed out that this does not mean that it is impossible, through “long training,” to separate from empirical knowledge those items of knowledge independent of experience. Kant pointed out that mathematics is an example of a priori knowledge [B4]. According to Kant, in temporal terms mathematical knowledge also of course “begins with experience”; but through long training, human reason gradually learns to abstract certain kinds of knowledge about quantity or shape from concrete experience, stripping away the empirical elements mixed into them. The existence of mathematics easily proves that human beings possess at least some a priori knowledge.[②]
The status of mathematics in modern science is self-evident; one might say that the frontier of science is the domain of mathematics. Yet precisely because mathematics is a priori and remote from experience, people often overlook its limitations. Kant says: “It now seems natural enough that, once one has left the ground of experience, one should not immediately build a structure on the basis of knowledge one possesses but does not know whence it comes, and on the authority of principles whose source one does not know, without first securing the foundation of that structure through careful investigation;”[B7] and the unlimited expansion of mathematics—to the point of extending its territory into morality and faith—is something Kant regarded with great alarm. Therefore Kant must make the question “How is mathematics possible?” or “How are synthetic a priori judgments possible?” the focal point of his concern.
Kant pointed out that a priori knowledge does not come from the object itself, but from the subject’s forms of cognition: “It is no wonder that the laws of appearances in nature must agree with the understanding and its a priori forms, that is, its capacity for combining the manifold in general, just as appearances themselves must agree with the forms of a priori sensible intuition. For laws do not exist in appearances, but only relative to the subject to whom the appearances adhere, insofar as this subject has understanding, just as appearances do not exist in themselves but only relative to that same being insofar as it has senses.”[B164]
Starting from empiricism, Kant rejects the Platonic realm of ideas; hence the source of mathematical knowledge cannot be such a vague and ethereal realm of ideas. At the same time, Kant distinguishes between analytic and synthetic judgments, and proves that mathematical knowledge is not analytic propositions, so its source cannot be mere logical deduction either. Ultimately, the source of mathematical knowledge is identified as the a priori forms of understanding; and this simultaneously establishes the source of natural scientific knowledge, because natural science is, at bottom, mathematical: “The understanding does not derive its laws (a priori) from nature, but prescribes them to nature.”[320]
Although knowledge comes from experience, it is understanding that makes experience possible. For example, “space,” as a thing-in-itself, has no determinate features at all; consequently one would not seek natural laws in it—“It is understanding that determines space as circular, conical, and spherical.”[321] Such a mathematical space, as an a priori form of cognition, makes possible our knowledge of laws of motion.
It is precisely because of the laws of understanding that we are able to know “nature” from experience. And it is also because the “nature” we experience is subject to the laws of understanding that it can be, and must be, mechanical and mathematical. Hence only then does the deterministic picture of a mechanical worldview become capable of being coordinated with moral reason and free will; I shall return to this later.
The Thing-in-Itself Is Unknowable
The important concept of Kant’s “thing-in-itself” has already been touched on above: what human beings can know is only “nature,” that is, the nature for which human understanding legislates, not the thing-in-itself: “Nature is the existence of things, insofar as this existence is determined according to universal laws. If nature is to mean the existence of things-in-themselves, then we can never know it either a priori or a posteriori;”[294]
The reason why the thing-in-itself cannot be known a posteriori had already been revealed in Hume. Kant says: “Experience tells me, indeed, what something exists and how it exists, but it never tells me that it must exist thus.”[294]
On the other hand, because all human cognition can never escape the limits of human cognitive capacity—human beings can know objects only through human modes of perception—Kant says: “What the object may be in itself, and apart from all this receptivity of our sensibility, remains completely unknown to us. We know nothing save our mode of perceiving them, a mode which is peculiar to us, and which, though it must be shared by every human being, need not be shared by every being. It is with this mode alone that we have to do. Space and time are its pure forms, sensation in general its matter.”[B59]
We often say that a congenitally color-blind person can never truly “know” what color is all about, even if he knows the corresponding wavelengths of various colors. Of course, he may come to know the limitations of his own senses through communication with those who are not color-blind; yet one can imagine that, as a whole, humankind’s sensory capacities are also limited. No matter how people use advanced instruments to extend the range of human perception, the condition of objects-in-themselves, beyond all sensibility, is something we can never know. We cannot rule out the possibility that there are beings outside humanity who possess modes of perception unimaginable to human beings; we can only know things as they appear to us, and can never understand how they appear in an entirely different form to other beings. Still less can we reach some absolute being that can transcend every form and directly know things. Perhaps God can know the thing-in-itself, but this is beyond human reach.
As for whether it is possible to know the thing-in-itself a priori, Kant points out, on the basis of the distinction between analytic and synthetic judgments, that since analytic judgments themselves do not expand knowledge, we cannot obtain knowledge of the thing-in-itself merely through analysis of concepts.
It is worth adding here that, in what follows, I will soon emphasize that Kant insists that things-in-themselves exist. But does “things-in-themselves exist” not amount to our a priori knowledge about things-in-themselves? One commentator has raised this point: “Kant further infers from the actuality of sensible cognition, or, more precisely, affirms the reality of things-in-themselves. This in fact violates to a considerable extent his own principle that things-in-themselves are unknowable. Knowing and knowing to a degree are two different concepts; to know the mere existence of something and to know fairly comprehensively all the properties of this thing differ only in degree and not in kind, so one cannot place the former outside the scope of knowledge while counting the latter as true knowledge. Clearly, Kant did not realize this relation, and so he both affirmed the existence of things-in-themselves and denied their knowability.”[③]
Yet Kant’s affirming the existence of things-in-themselves while denying their knowability is not a contradiction; Kant is not bringing the existence of things-in-themselves into the domain of understanding, just as he does not bring their unknowability into it either—existence and unknowability are not properties of things; they are not the result of understanding, but a necessary demand of reason.
The distinction between reason and understanding is a distinctive feature of Kant’s philosophy, and this important distinction was not inherited by the philosophers after Kant. Kant points out that people have long “confused concepts of understanding with concepts of reason” [329], producing a muddled understanding of the limits of understanding. In fact, this confusion became even more pronounced in modern philosophy: philosophers split into one camp of scientism, believing that science encompasses everything, and another camp of irrationalists who emphasize emotion and impulse, as if any attempt to place limits on science would necessarily require exalting the irrational. This is precisely because understanding and reason have been conflated. But the reason Kant emphasizes is something different from understanding; one must use reason to examine and reflect upon understanding. Kant says: “Reason never has an immediate relation to experience or to any object, but rather to the understanding” [B359].
In addition, Kant’s famous refutation of the ontological proof of God’s existence also corroborates, from another angle, the significance of “the existence of things-in-themselves.” Kant says: “In the mere possibility, there is not more contained than in the actuality. A hundred actual thalers do not contain the least bit more than a hundred possible thalers. For, since the former signify the concept, while the latter signify the object and its positing in itself, if the object contained more than the concept, then my concept would not express the whole object, and would therefore not be a suitable concept of it. But in my state of possession, a hundred actual thalers contain more than the mere concept of them—that is to say, than the concept of their possibility. For the object is not merely analytically contained in my concept, but is added to my concept (which is a determination of my state) synthetically; and through this existence outside my concept, my concept does not gain the least enlargement.” [B627] This argument is generally understood as showing that existence cannot be inferred from a concept; however, it also clearly expresses the proposition that “existence is not knowledge.” Whether a thing exists is of course not meaningless, but existence as such does not provide any knowledge; only when “existence” is synthetically, rather than analytically, added to other concepts does it become meaningful.
The existence of things-in-themselves is likewise not knowledge; as such, it cannot positively expand our knowledge. When Kant speaks of God, he continues: “The concept of a supreme being is an idea which, in many respects, is very useful; but precisely because it is only an idea, it is quite incapable of extending by itself alone our knowledge with regard to existence.” [B629] Here, the supreme being (which in a certain sense is also the thing-in-itself) is similar in meaning to the thing-in-itself: whether it exists or not does not help expand knowledge; rather, it is more a limitation upon knowledge.
Thus we begin to enter Kant’s distinctive doctrine of ontology, an ontology that is not meant to expand knowledge positively, but to limit knowledge negatively.
Things-in-Themselves as Negative Ontology
Earlier we mentioned that affirming the existence of things-in-themselves while denying their knowability is not contradictory. However, why does Kant go to such pains to emphasize the existence of things-in-themselves? As noted above, Kant’s ontological doctrine is not an attempt to expand knowledge positively, but to set limits on knowledge negatively. I will return later to Kant’s claim that foundation is limitation; for now, following the previous discussion, I will continue to discuss the significance of “thing-in-itself” as a negative ontology.
First, it should be pointed out that in Kant the concept of the thing-in-itself is discussed mainly in epistemological terms, but at the same time Kant also places the thing-in-itself in an ontological position.
Kant says:
“We can have no knowledge of any object as a thing-in-itself, but only insofar as it is an object of sensible intuition, that is, as appearance; from this it follows, of course, that all speculative knowledge of reason is confined solely to objects of experience as such. Nevertheless, one must note here that there is always a reservation, namely, that these same objects, as things-in-themselves, though we cannot know them, must at least be able to be thought. For otherwise there would follow the absurd proposition that there is appearance without something that appears.”[BXXVI]
“In fact, if we regard the objects of the senses, as is fitting, as mere appearances, then we thereby also at the same time acknowledge that they have a thing-in-itself as their ground, even though we do not know what this thing is like in itself, but only its appearance, that is, the way in which our senses are affected by this unknown something. Thus it is precisely by acknowledging appearances that the understanding also acknowledges the existence of things-in-themselves,” [314]
Here Kant emphasizes that although things-in-themselves cannot be known, they must be able to be “thought,” and furthermore ought to be “acknowledged.” It should be noted that “acknowledged” does not mean “known”; as mentioned earlier, there is no contradiction here.
Through his acknowledgment of things-in-themselves, Kant draws a line between himself and traditional idealism. He says: “I have never thought of doubting the existence of things,” [293] Here, of course, one may take Kant’s insistence as a kind of belief, and Kant’s doctrine of things-in-themselves is indeed emphasized precisely to leave room for faith. But Kant’s reason for acknowledging things-in-themselves here is not merely belief; more fundamentally, it is a demand of reason.
Because of the principle of sufficient reason on which synthetic judgments depend, we cannot allow a situation in which I see an appearance, yet that appearance is entirely without cause. Reason necessarily needs to inquire into the source of appearances; otherwise, the appearance is absurd and unintelligible to us. If all appearances were “mysterious,” why would we seek regularity and order in appearances? The precondition for understanding appearances is that they be intelligible. Therefore appearances must be stimulated by something unknown.
No matter where this thing-in-itself is, no matter what it is like, as the source of appearances it must certainly exist. Yet because it transcends the limits of understanding, this thing that stimulates our senses and gives us appearances is unknowable, a point already discussed above.
Positivists will declare that since it is unknowable, it is meaningless and ought to be cut away by Occam’s razor. Yet, as noted above, Kant distinguishes between understanding and reason: although things-in-themselves lie outside the scope of understanding, they are a necessary demand of reason. And, more importantly, things-in-themselves will be a necessary condition for the possibility of practical reason; I will return to this later.
Thus, the thing-in-itself is roughly equivalent to Kant’s ontology—Kant on many occasions juxtaposes the two words as “thing-in-itself (noumenon)” [312][360]. As ontology, the thing-in-itself is obviously entirely different from traditional ontology.
It is worth mentioning, however, that Kant’s thing-in-itself is in some respects close to Aristotle’s “matter” (“hylē”). For Aristotle, matter is “imperceptible and unknowable,” because sensation perceives only form combined in matter, while intellect knows only form not combined with matter. And what we can have clear concepts of are all forms, and forms are precisely not matter.[④]
In the *Metaphysics*, Aristotle says: “By matter I mean that which in itself is neither a this nor of a certain quantity nor any of the things by which being is determined.”[⑤] This stands in sharp contrast to the modern common understanding that “matter is a unity of mass.”
However, Aristotle did not identify matter as “substance”; he says: “For substance is primarily that which is independent and individual. Substance, rather than matter, should be called the universal form and the combination of universal form and matter.”[⑥]
In other words, Aristotle’s “matter” is similar to the modern concept only in the sense of the “material” out of which everything is constituted; but the substance of all things discussed in modern atomic theory, electron theory, and so on, according to Aristotle, and those descriptions of all kinds of structures and rhythmic motions “are all a kind of theory of form, and are not theories of matter at all.”[⑦]
According to Aristotle’s distinction, “matter,” as the “material” constituting all things, is something without determinations of quality or quantity and thus imperceptible; “form,” by contrast, is what has quality and quantity and is perceptible. In modern times, these two concepts were again conflated. Matter, while remaining the material constituting all things, also acquired determinations of quality and quantity
It can be said that Kant had already recognized modern people’s conflation of matter and form—and in Aristotle, matter is precisely that which alone cannot be conflated with form. Kant’s distinction between what is perceptible and mathematically formalizable, on the one hand, and matter—that is to say, the essence of things—as imperceptible and non-mathematical, on the other, can be said to be a return to Aristotle. Of course, unlike Aristotle at the most fundamental level, form in Kant comes from the subject. On the other hand, Kant likewise does not identify the thing-in-itself with the traditional sense of substance; what he calls the positive ontology, by contrast, is regarded as a “negative ontology”:
If by a noumenon we understand a thing in so far as it is not an object of our sensible intuition, and so abstract from our way of intuiting it, then this is a noumenon in a negative sense. But if we understand by it an object of a non-sensible intuition, then we assume a special way of intuiting, namely the intellectual, which is not our way of intuition, and of whose possibility we cannot see the least trace; this would be a noumenon in the positive sense.[B307] See also [A252]
The significance of a negative ontological concept lies in restraining human arrogance—namely, in refusing to take one form of intuition, one that is fundamentally limited, as the only possible and dogmatic form, and then applying it to domains beyond its boundaries.
“The concept of a noumenon, that is, of a thing that must not be thought of as an object of the senses, but rather as a thing-in-itself (merely through pure understanding), is not at all self-contradictory; for one cannot assert of sensibility that it is the only possible kind of intuition. Furthermore, in order not to extend sensible intuition to things-in-themselves, and thereby to limit the objective validity of sensible knowledge, this concept is also necessary (because those things that sensible intuition does not reach are called noumena precisely in order to indicate by this that the sphere of sensible knowledge cannot extend to everything that the understanding thinks).”[B310]
Kant plainly points out: “The concept of a noumenon is merely a limiting concept, for the purpose of restraining the pretensions of sensibility, and therefore has only negative use.”[B311]
Foundation Is Limitation
If it is only a limiting concept with a negative function, then why call it “ontology”? Is ontology not the original source or primordial ground of all things? Is ontology not the “foundation” of all knowledge? When we speak of “foundation,” what comes to mind is often the laying of a building’s cornerstone. This metaphor is not wrong, but it can easily mislead people into thinking that ontology is the root or seed of a great tree, from which all knowledge grows or is deduced—this may be the traditional understanding of ontology; however, in Kant, ontology is not such a “seed.” If ontology is like the foundation of a theoretical edifice, then one thing deserves special attention: the extremely important function of the foundation is that it determines the scope of construction. Builders can only build within the boundaries established by the foundation and cannot casually overstep them.
Kant gives a more brilliant metaphor for foundation:
The light dove, in free flight cleaving the air and feeling its resistance, might imagine that it would fare even better in space without air. In the same way, Plato left the sensible world because it sets understanding such narrow limits, and ventured to fly beyond it on the wings of ideas, into the empty space of pure understanding. He did not notice that he made no progress at all, in spite of all his efforts, because he had no support, as it were no foundation, to stand on and from which he could exert force in order to move the understanding.[B9]
Just as the foundation, as the support of a building, is also the boundary that determines the building’s scope. Air is both resistance to flight and the foundation that supports flight. Foundation is always at the same time limitation. So it is in Kant’s work on metaphysics: on the one hand, he wants to establish a solid metaphysical foundation for knowledge (natural science and moral philosophy), but at the same time Kant understands that a solid foundation will precisely appear as obstruction and limitation. Yet if one tries to rid oneself of this obstruction and limitation, one does not gain freedom, but becomes unable to move an inch. Thus, in Kant, setting limits for knowledge and laying a foundation for knowledge are one and the same task. From this, we can more easily understand Kant’s conception of the task of metaphysics: “not with the aim of extending knowledge itself, but merely with the aim of correcting knowledge.” [B26]
As mentioned above, Kant is committed to limiting the scope of mathematics, or rather the scope of mechanics, that is, the mechanistic view of nature. “Neither pure mathematics nor pure natural science can concern itself with anything beyond mere appearances” [312] Yet this delimitation is not meant to fetter the development of mathematics or natural science. On the contrary, it is meant to allow science to develop more freely.
For skeptics—and in modern terms, extreme relativists—because they reject law, they fall into a state of anarchy; just as in a lawless age of chaos, people may seem to have shaken off all formal constraints, but what they obtain is not freedom, only confusion.
And among dogmatists, science too is without limits; however, because they overestimate the capacity of human understanding and think that knowledge can be expanded through deduction from concepts, dogmatists often believe that knowledge is finite—dogmatists arrogantly think that one day, or indeed right now themselves, people will possess an absolute, completed system of knowledge. Kant, by contrast, explicitly rejects this vain fantasy, emphasizing that setting limits for knowledge does not mean fixing the boundary of knowledge once and for all:
“As soon as cognitions of reason are homogeneous, one cannot think of them as having any determinate limits. In mathematics and natural science human reason indeed admits restrictions, but not limits, that is, although it admits that there is something beyond it which it can never reach, it does not admit that within its own internal progress it will ever come to an end somewhere. The expansion of knowledge in mathematics and the possibility of ever new inventions are unlimited. Likewise, the discovery of new properties of nature, new powers and laws, through the advance of experience, and their unification by reason, is also unlimited. But here one must still not ignore the restrictions, because mathematics is concerned only with appearances, and whatever cannot be an object of sensible intuition, such as the concepts of metaphysics and morality, lies completely outside its sphere,” [352]
That is to say, Kant’s limiting of science does not mean correcting knowledge within science, but rather correcting science’s encroachment into other domains. Kant points out that, fundamentally, letting science run free is in fact a restriction on reason—for it will prevent the practical use of reason from unfolding. Kant remarks: “Although the transcendental ideas do not help us in positive instruction, they do nonetheless help to banish the presumptuous claims of materialism, naturalism, and fatalism, which narrow the field of reason, and thus create room for moral ideas beyond the sphere of speculation.” [363]
Kant says: “These unavoidable tasks of pure reason itself are God, freedom, and immortality. But the science whose ultimate aim and all of whose preparations are directed precisely to their solution is called metaphysics.” [B7] It is clear, then, that moral philosophy and philosophy of religion are in fact the highest concerns of Kant’s ontology, or metaphysics.
So then, how does placing limits on knowledge provide a guarantee for the development of morality and religion? The question in this respect will of course be taken up later in the *Critique of Practical Reason* and a series of other works. In the *Critique of Pure Reason*, Kant mentions an important example of the role of things in themselves: namely, the possibility of a free will that is not inconsistent with a mechanistic view of nature:
“The same will, therefore, in the appearance (visible action) is thought as necessarily conforming to the law of nature, and to that extent is not free; but on the other hand it is thought as belonging to a thing in itself that is not subject to the law of nature, and is thus thought as free; there is no contradiction here. Now even if, from the latter point of view, I cannot know my soul by means of speculative reason (still less by empirical observation), and therefore cannot know freedom as the property of a being to which I ascribe the effects of the sensuous world, because I must know it in accordance with the existence of such a being, but cannot determinately know it in time; nevertheless, I can think freedom, …, the representation of freedom at least does not itself contain any contradiction. Now if morality necessarily presupposes freedom as a property of our will, …, but speculative reason proves that freedom cannot be thought at all; then that presupposition, namely the moral presupposition, would necessarily have to give way to its opposite presupposition, which contains an obvious contradiction, and thus freedom together with its morality would necessarily have to give way to natural mechanism. But in that case, since for morality I no longer need anything else, provided only that freedom does not contradict itself, and is therefore at least thinkable, without there being any need to comprehend it further, and since it thus creates no obstacle whatever to the natural mechanism of the same action (when viewed from another relation), the doctrine of morality retains its place, and the doctrine of nature also retains its place; yet this would not happen unless criticism first taught us that we are inevitably ignorant of things in themselves, and limited all that we can know theoretically to appearances alone.”[BXXVIII- BXXIX]
Put simply, the distinction between reason and understanding, and the limitation of knowledge, ensure that “freedom,” though it cannot be known or proven, and even though it runs counter to the picture supplied by natural science, is nevertheless thinkable. The “I” as an object of understanding’s reflection, like all appearances, is subject to the deterministic laws of nature; yet the “thing in itself” that lies beyond the reach of understanding transcends the limits of natural law, and thus it is possible to speak of its “freedom.” And as for why we must presuppose it as the premise of practical reason, Kant will address that in his later works.
Kant’s place in the history of philosophy needs no elaboration. As the Japanese scholar Abe Yōsei put it, “Kant is a reservoir: all earlier philosophy flows into him, and all later philosophy flows out from him.” All the schools and currents of modern philosophy have, without exception, been inspired by Kant’s philosophy. And yet, how many true heirs are there to the philosophical method Kant founded, and to its basic philosophical concern?
On this point, I must sadly say: almost none at all!
This is not an overstatement. The discussion above has already suggested that “negative ontology,” that is, the “doctrine of things in themselves,” “is an important component of Kant’s philosophy. It runs through all of Kant’s critical philosophy and is the basic background and prerequisite of his philosophical discussion.”[⑧]
Yet what came nominally after Kant were, first, German Classical Idealism represented by Fichte and Hegel, and later Neo-Kantianism represented by the Marburg School—no matter which parts of Kant’s philosophy one says they inherited and developed, they all rejected or discarded the thing in itself as negative ontology, which Kant emphasized.
Fichte and Hegel both racked their brains trying to find a way to reach the thing in itself, and Hegel’s philosophy in particular moved toward an unprecedented arrogance. And although Kant too proudly advertised the greatness of his own achievements, the more important keynote of Kant’s philosophy is precisely “humility”:
Beyond the well-known expressions of awe and humility before the starry heavens and the moral law, the *Critique of Pure Reason* may be said to express humility regarding the capacities of human understanding; and on the other hand, Kant also emphasized humility on the part of the philosopher:
“From now on all schools will learn that, in questions involving the universal affairs of humanity, they should not pretend to have insights higher and broader than those that the broad masses, who for us are the most worthy of attention, can just as easily attain; and thus they should confine themselves merely to the cultivation of those universally intelligible, morally sufficient grounds of proof. For the reform concerns only the pretensions of the schools, which like to have themselves regarded here (as they are usually entitled to do in many other places) as the sole connoisseurs and custodians of such truths, passing on merely the use of these truths to the public, while keeping the keys to the truths themselves in their own hands.”[BXXXII]
Kant believed that the philosopher’s task is not to provide the masses with truth—“it is impossible to provide a sufficient and at the same time universal criterion of truth.”[B84]
Although Neo-Kantianism was divided into many schools, its common feature was rejection of the thing in itself. For example, the Marburg School within it held that “since an extreme monism of thought excludes the status of sensuous cognition in knowledge and the role of the sensory element in the constitution of scientific knowledge, it undoubtedly has to deny the sensuous thing in itself as the cause of sensory material, and because it recognizes only that world of nature created by mathematical natural science as the sole world of nature, it is also necessarily unable to acknowledge any existence of a thing in itself as the basis of that natural world. Thought is the beginning of being, the source of being; thought can and should discover being within itself. In order to further substantiate this idea, they also attempted to explain the constitution of the natural world by means of number as a product of thought, and thus returned to the views of Pythagoras and Plato. Therefore, in the development of Neo-Kantian thought, we can see a phenomenon of a shift from Kant toward Hegelianism.”[⑨]
And as we have already said, Kant’s most important effort lay in restricting the unlimited expansion of mathematics; in this respect, Neo-Kantianism not only failed to inherit Kant, but rather moved directly against him.
The various schools of the rest of modern philosophy, taking rejection of metaphysics as their point of departure, not only rejected the traditional positive ontology, but also rejected—or rather, paid no heed to—Kant’s negative ontology, that is, they evaded the question of placing limits on knowledge. Thus modern philosophy naturally split into two extreme camps, scientism and irrationalism. And by the latter half of the twentieth century, although all sorts of schools had, in one way or another, shown a renewed recognition of metaphysics, still very few people carried on Kant’s achievement of setting limits to knowledge. The intellectual world once again displayed oppositions such as modernity and postmodernity, universalism and relativism, and so on.、
When it comes to science, people either enshrine it as “omnipotent” or else take it to mean “anything goes” — in the final analysis, the present situation is still no different from the lawless confrontation between the despotic monarch and the nomad that Kant described. A democratic, lawful, free realm of thought has still not been realized—and more sadly still, it seems that very few are any longer devoting themselves to this cause.
*Critique of Pure Reason*, trans. Li Qiuling, China Renmin University Press, 2004
*Complete Works of Kant (Vol. 4)*, trans. Li Qiuling, China Renmin University Press, 2005
*Kant on God and Religion*, ed./trans. Li Qiuling, China Renmin University Press, 2004
Han Shuifa, *A Study of Kant’s Doctrine of Things in Themselves*, Commercial Press, 2007
[Eng.] Collingwood, *The Idea of Nature*, trans. Wu Guosheng, Peking University Press, 2006, p. 109
Aristotle, *Metaphysics*, Commercial Press, 1959
[U.S.] Paul Guyer, *The Tree of Philosophy*, trans. Zhai Pengxiao; proofread by Wang Lingyun, Guangxi Normal University Press, 2005
[U.S.] Garrett Thomson, *Kant*, trans. Zhao Chengwen, Teng Xiaobing, and Meng Lingpeng, Zhonghua Book Company, 2002
Deng Xiaomang, *Lectures on Kantian Philosophy*, Guangxi Normal University Press, 2005
[①] All of Kant’s original text quoted in this article is taken from the translation by Li Qiuling, mainly from: *Complete Works of Kant (Vol. 4)*, trans. Li Qiuling, China Renmin University Press, 2005; and *Critique of Pure Reason*, trans. Li Qiuling, China Renmin University Press, 2004. For the sake of brevity, edge numbers in *Complete Works of Kant (Vol. 4)* are marked in the text in the form “[271],” while edge numbers in *Critique of Pure Reason* are marked in the form “[AXII],” “[B252],” and so on.
[②] Of course, Kant did not take into account the problems that might face Euclid’s fifth postulate, but in any case non-Euclidean geometry is still a kind of a priori knowledge that transcends empirical factors. The emergence of non-Euclidean geometry and relativity, and so on, merely proves that Kant was after all a mortal man, but it is by no means enough to fundamentally invalidate Kant’s approach. Incidentally, if we extend Kant’s theory in mathematics, we find that number theory has in fact already made certain transgressions, introducing the real infinite, an element that oversteps the limits of human understanding. In fact, according to Kant’s transcendental dialectic, with regard to the infinite, human beings can think it but cannot “know” it; “knowledge” of the infinite will produce a kind of illusion. And the series of paradoxes that later erupted during the third crisis in mathematics were without exception caused by abuse of the actual infinite. Kant was farsighted in this respect; no wonder later intuitionists (who opposed the actual infinite) took Kant as their intellectual forerunner.
[③] Han Shuifa, *A Study of Kant’s Doctrine of Things in Themselves*, Commercial Press, 2007, p. 73
[④] [Eng.] Collingwood, *The Idea of Nature*, trans. Wu Guosheng, Peking University Press, 2006, p. 109 (edge number P91)
[⑤] Aristotle, *Metaphysics*, 1029a20: here I have consulted the translation in *The Idea of Nature*.
[⑥] Aristotle, *Metaphysics*, 1029a29 and following
[⑦] [Eng.] Collingwood, *The Idea of Nature*, trans. Wu Guosheng, Peking University Press, 2006, p. 109 (edge number P91)
[⑧] Han Shuifa, *A Study of Kant’s Doctrine of Things in Themselves*, Commercial Press, 2007, p. 17
[⑨] Han Shuifa, *A Study of Kant’s Doctrine of Things in Themselves*, Commercial Press, 2007, p. 161
Translated from the Chinese original with AI assistance. The original text is authoritative.
Leave a Reply