190 Kant: A Biographyend of his "precritical period" and as the beginning of his "critical phi¬
losophy." Thus when he was approached by Johann Heinrich Tieftrunk
about the publication of a collection of his minor writings in 1797, he
answered: "I accept your proposal of putting together a collection of my
minor writings. However, I would not like to have included anything be¬
fore 1770, so that it would begin with my dissertation de mundi sensibilis et
intelligibilis forma.. ."^5
One of the most important new doctrines of Kant's Inaugural Disser¬
tation was his radical distinction between "intellect" and "sensation." In
this work Kant for the first time explicitly argued that these two faculties
are independent and irreducible sources of two entirely different kinds of
knowledge. He defined sensibility as "the receptivity of the subject through
which it is possible that its representative state be affected in a certain man¬
ner by the presence of an object," and intelligence as the "faculty of the
subject through which it is able to represent things which cannot by their
own nature come before the senses of their subject."^6 Intellectual knowl¬
edge has nothing in common with sensitive knowledge. Indeed, he argued
that we must assume two worlds, a mundus intelligibilis and a mundus sen¬
sibilis. Each of these worlds obeys its own principles and exhibits forms
peculiar to it, and each of them has its own objects: "The object of sensi¬
bility is the sensible, that which contains nothing but what is to be cognised
through the intelligence is intelligible. In the schools of the ancients the
former was called phenomenon and the latter a noumenon."^7 Phenomena are
"representations of things as they appear," noumena are "representations
of things as they are."^8 It would therefore be a serious mistake to regard
sensibility as nothing but confused thinking, or thinking as nothing but
distinct sensation. To use Kant's own words, "The sensitive is poorly de¬
fined as that which is more confusedly cognised, and that which belongs to
the understanding as that of which there is a distinct cognition. For these
are only logical distinctions which do not touch at all the things given, which
underlie every logical distinction."^9 Kant singled out for special criticism
"the illustrious Wolff," who "has, by this distinction between what is sen¬
sitive and what belongs to the understanding, a distinction which for him
is only logical, completely abolished, to the great detriment of philosophy,
the noblest of the enterprises of antiquity, the determining of the charac¬
ter of phenomena and noumena.. ."^10 Yet Kant believed that not just Wolff
but every modern philosopher, more or less uncritically, had accepted this
thesis. By contrast, he wanted to return to the enterprise of antiquity, pro¬
claiming the necessity of a "genuine metaphysics without any admixture