According to Kant (1781), immanent principles are those whose application is confined within the limits of possible experience, while transcendent principles are those whose application transgresses the limits of possible experience. Transcendental principles are those concerned with our mode of cognition of empirical objects, insofar as this mode of cognition is possible a priori. Thus, transcendental principles do not transcend or transgress the limits of possible experience, but rather make knowledge of experience possible.
A.C. Ewing (1938) describes the distinction between the transcendent and the transcendental by saying that the transcendent refers to what is not a possible object of experience, and that transcendent knowledge is therefore impossible. The transcendental, on the other hand, refers to the necessary conditions of experience, and transcendental knowledge is therefore certainly possible.1
Transcendental idealism, as described by Kant, is the theory that all objects of possible experience are merely representations having no self-subsistent existence apart from human thought. Transcendental realism, on the other hand, is the theory that objects of possible experience are things subsisting in themselves, which are real independently of their representations in human thought.2
Faculties of cognition, according to Kant, include intuition, understanding, judgment, and reason. Intuition is a lower faculty of cognition, while understanding, judgment, and reason are higher faculties of cognition. Intuition is the faculty of receiving impressions. Understanding is the faculty of producing rules or concepts. Judgment is the faculty of determining whether a rule or concept is subsumed under other rules or concepts. Reason, the highest faculty of cognition, is the faculty that produces principles.
While the categories (of quantity, quality, relation, and modality) are conceptions of pure understanding, transcendental ideas are conceptions of pure reason. While the objective employment of pure conceptions of understanding is always immanent, the objective employment of pure conceptions of reason is always transcendent.3 Reason never applies directly to experience or to any empirical object. Its object is rather the understanding, to the manifold cognition of which it gives unity a priori by means of conceptions.4
The principles of pure understanding are immanent but not transcendent principles, insofar as they are applicable to objects of possible experience, but not to objects beyond the limits of experience.5
Thus, transcendental illusion may occur when immanent principles are mistaken for transcendent principles.
The pure conceptions of understanding apply a priori to (empirical or non-empirical) objects of intuition.6 Transcendental ideas, on the other hand, are conceptions of pure reason whose objects are not empirical, but are objects of pure understanding.7 Transcendental ideas are also transcendent, insofar as they transgress the limits of possible experience. Their objects are cognitions to which no actual experience ever fully attains. No object can ever be perfectly adequate to a transcendental idea.
Thus, the transcendental employment of reason is not objectively valid, since all a priori cognitions are given their objective validity by their possibility of experience.8
When we mistakenly regard transcendental ideas as conceptions of actual things, their mode of application is not only transcendent, but also delusive. However, it is not a transcendental idea itself, but only its application, in relation to possible experience, that is immanent or transcendent. A transcendental idea is applied immanently when it is applied only to an object within the limits of experience. It is applied transcendently when it is applied to an object beyond the limits of experience or to an object falsely believed to be adequate with, and to correspond to, it.9
Principles of pure understanding may be classified as (1) axioms of intuition, (2) anticipations of perception, (3) analogies of experience, and (4) postulates of empirical thought. While the first two classes may be described as mathematical, the second two may be described as dynamic.10 The mathematical principles are constitutive principles of understanding, while the dynamic principles are regulative principles of understanding.
Transcendental ideas may be regulative principles of understanding, but they are not constitutive principles, since they are not based on empirical intuition. Indeed, contradictions may arise when they are confused with constitutive principles. However, they may still guide our understanding of the empirical world, and pure reason may therefore act as a regulative principle to guide the production of rules and concepts.
FOOTNOTES
1A.C. Ewing, A Short Commentary on Kant's Critique of Pure Reason (Chicago: The University of Chicago Press, 1938), p. 25.
2Immanuel Kant, Critique of Pure Reason, translated by J.M.D. Meiklejohn (Amherst: Prometheus Books, 1990), p. 278.
3Ibid., p. 205.
4Ibid., p. 191.
5Ibid., p. 205.
6Ibid., p. 61.
7Ibid., p. 205.
8Ibid. p. 97.
9Ibid., p. 360.
10Ibid., p. 114.
