Third Stage.—A 119-23 = III. β; A 116-19 = III. α; A 94-5 = I. § 14 C(oncluding paragraph); A 126-8 = III. δ; A 128-30 = S(ummary); A 123-6 = III. γ; A 115-16 = III. I(ntroduction); A 76-9 (B 102-4) = § 10 T(ransition to fourth stage).
A 119-23, III. β (from the beginning of the seventh paragraph to the end of the twelfth). The doctrine of objective affinity already developed in the above sections is now made to rest upon a new faculty, the productive imagination. As Vaihinger remarks, the wording of this section would seem to indicate that it is Kant’s first attempt at formulating that new doctrine. He has not as yet got over his own surprise at the revolutionary nature of the conclusions to which he feels himself driven by the exigencies of Critical teaching. He finds that it is deepening into consequences which may lead very far from the current psychology and from his own previous views regarding the nature and conditions of the knowing process and of personality. As evidence that this section was not written continuously with II. 4, [821a] we have the further fact that though the doctrine of objective affinity is dwelt upon, it is described afresh, with no reference to the preceding account. Also, the empirical processes of apprehension and reproduction, already mentioned in A 104-10, are now ascribed to the empirical imagination which is carefully distinguished from the productive.
III. α repeats “from above” the argument given in III. β “from below.” It insists upon the close connection between the categories (first introduced in II. 4[821]) with the productive imagination of III. β.
Vaihinger places III. δ next in order, on account of the connection of its argument with III. α.[822] But it dwells only upon the chief outcome of the total argument, viz. that the orderliness of nature is due to understanding. That productive imagination is not mentioned, is taken by Vaihinger to signify Kant’s recognition that it can be postulated only hypothetically, and that as doctrine it is not absolutely essential to the strict deduction.
S summarises the entire argument, and in it “pure imagination” receives mention.
Within this third stage III. γ is subsequent to the above four sections. For it carries the doctrine of productive imagination one step further. In III. β, III. α, and S, productive imagination has been treated merely as an auxiliary function of pure understanding.
“The unity of apperception in relation to the synthesis of imagination is the understanding; and the same unity with reference to the transcendental synthesis of the imagination is the pure understanding.”[823]
It is now treated as a separate and distinct faculty. So far from being a function of understanding, its synthesis “by itself, though carried out a priori, is always sensuous.”[824] It is
“one of the fundamental faculties of the human soul.... The two extreme ends, sensibility and understanding, must be brought into connection with each other by means of this transcendental function of imagination.”[825]
In this section there also appears a new element which would seem to connect it with the next following stage, namely, the addition to the series, apprehension, association, and reproduction, of the further process, recognition. As here introduced it is extremely ambiguous in character. It is counted as being empirical, and yet as containing a priori concepts. This decidedly hybrid process would seem to represent Kant’s first formulation of the even more ambiguous process, which corresponds to it in the fourth stage.