Ⅱ．Limitations of Cognition in Kant's Philosophy

Although the focus of this paper is not to analyze the cognitive process of human beings in Kant's philosophy, that is, the subject and object establish the cognitive category and “mechanism” of human beings through sensibility,intellectuality and rationality, but if we want to analyze the limitations of the two questioning methods (empirical science and pure rational law), we can't get around this problem. In Kant's philosophy, noumena, or transcendens,exists outside the category that experience can know, and limits our knowledge to the visualization world. In this sense, all attempts to go beyond experience and directly describe thing-in-itself will inevitably end in failure. However,this does not mean that there is no knowledge in any sense. And the rational comprehensive judgment a priori (note that a priori can never be understood as being equal to transcendental experience, otherwise it will be the root of misunderstanding) will root the law in our knowledge. In other words, it is precisely because of the regularity of the innate comprehensive judgment that the “relationship” between the phenomenal world and the law with universal inevitability corresponds to experience and rationality. As Kant pointed out,“This system precedes all empirical knowledge of nature, and first makes this knowledge possible, so it can be called real, universal and pure natural science.”

At this time, if people want to ask about thing-in-itself (as a curious creature), there will be two ways. First, extend the rationalized scientific laws beyond experience, and understand thing-in-itself in an empirical way. Second, the concept of pure research category, that is, the study of pure rationality. However, either way is contradictory and fails, as will be demonstrated below.

The first way to ask about thing-in-itself is to regard the law of phenomena as the law of thing-in-itself, but there are two problems.In fact, this is essentially a misunderstanding of Kant. Kant's understanding of the object does not refer to the object itself, but the object after being recognized by perceptual knowledge. In other words, Kant suspended the object as the object itself, because it was meaningless, but only to legislate for the visualization world connected with the senses. Therefore, all knowledge beyond visualization, or beyond experience, no longer has universal inevitability. Let's explore further. All knowledge itself is not only an empirical judgment or analytical judgment (the object word exists in the subject word a priori),but an empirical comprehensive judgment, and only in this way can it have universal inevitability.

Therefore, the boundary between knowledge and reason, as Kant pointed out, “What is involved in proving is not the comprehensive unity of the connection of thing-in-itself, but the comprehensive unity of the connection of perception, and this is not in terms of the content of perception, but in terms of the time rules and relationships existing in perception according to universal laws.” Therefore, back to the questioning method put forward at the beginning of the above paragraph, the f irst absurdity of this method lies in extending the limits of knowledge beyond the legislative possibility, artificially and arrogantly expanding the rules that can be established by pure experience categories.

Kant put forward the concept of category and the concept of table of judgments in Critique of Pure Reason . They are: full name, special name, and singular name. Aff irmative, negative, inf inite. Categorical,hypothetical, disjunctive; problematic, assertoric, apodeictic. A priori intellectual concept table: oneness, multiplicity, and totality. reality,negation, and limitation; substance, cause, association. Possibility,existence, inevitability. These judgment appellations are transcendental proposition forms due to the relationship between transcendental rationality and intellectuality, which are inevitable and reasonable. It has been suggested that since these categories are not the categories of experience,can we know noumena by tracing back the categories?

In my opinion, this view is far more attractive than the first attempt,but unfortunately it is also paradoxical. First of all, these propositional forms(predicates) are indeed transcendental knowledge forms and categories,but as far as their functions are concerned, they must be combined with experience. Take identity as an example. There are three meanings.

a．Relationship between the subject word and the object word, which only works in experience. Predicate is out of context, out of the relationship between subject and object, and it will not have “meaning” by itself. Kant pointed out: “Because people add some predicates to them (noumena beings), these predicates are only used to make empirical and regularity possible. However, all intuitive conditions are removed from them, and only under these conditions is experience possible. As a result, those concepts lose their meaning again.” In conclusion, language is conditional,and the condition of language is called experience.

b．Even though it is admitted that the predicate divorced from experience can express “form”, it still can't bring knowledge, so all analysis is meaningless. Knowledge, as mentioned before, is the product of comprehensive judgment, and the unity of innate judgment and empirical judgment. That is to say, from “a is b”(perceptual experience judgment), it is generalized through comprehensive form (universality) to “a has the attribute of b universally” in experience. However, after the empirical judgment is stripped off, the predicate only expresses the form of innate judgment, and at this time all research will degenerate into innate analysis and judgment.At this time, all research is a restatement of the knowledge that has already been acquired, In the analysis and judgment, this predicate form has been rooted in the knowledge system. At this time, no form of knowledge has been produced, because knowledge means creation combined with experience.

c．The existence of predicate means the inevitable absence of absolute subject. “Pure rationality requires that we should give every predicate of a thing a subject that belongs to it. This subject must be a predicate, and we should look for a subject that belongs to it, and so on, so that it is infinite...Therefore, we should not be regarded as the ultimate subject by anything that can be achieved.”

Secondly, there is a second absurdity in this view. When we add empirical science or knowledge to the thing-in-itself, anthropomorphism will be born, which is demonstrated in detail in the fourth antinomy. Hume pointed out, “Anthropomorphism makes theism self-contradictory.” Note that the intention here is by no means to criticize the existence of theology,on the contrary, the category of theology should exist, but only to criticize the fallacy of anthropomorphism. Because this kind of questioning means that “I” endows the highest being (noumena) with will.

Kant pointed out: “My experience is still the same, because I have this concept only because I got it from my internal experience, but here is the dependence of my satisfaction on the actual objects we need, so it is based on sensibility, which is completely contradictory to the pure concept of the supreme being (God as an idea).” In other words, if the all-knowing,all-powerful, and all-good “God who exists as a personality” assumed by traditional theology exists, then he is just an “idol” established by man through his own will, and does not have the absoluteness of his “meaning”.The image of God will completely collapse into the idol existence summarized by Feuerbach in The Essence of Christianity . Therefore, for whatever reason, the second attempt is absurd.