to
those of Resemblance, Identity, Time and Place, Quantity or Number,
Quality, Contrariety, Cause and Effect.

These attempts at an exhaustive distribution of the necessary
relations of all objects of knowledge indicate the direction taken by
modern thought, before it received its complete expression from Kant.

Kant.

The doctrine of the categories is the very kernel of the Kantian
system, and, through it, of later German philosophy. To explain it
fully would be to write the history of that philosophy. The categories
are called by Kant Root-notions of the Understanding (_Stammbegriffe
des Verstandes_), and are briefly the specific forms of the a priori
or formal element in rational cognition. It is this distinction of
matter and form in knowledge that marks off the Kantian from the
Aristotelian doctrine. To Kant knowledge was only possible as the
synthesis of the material or a posteriori with the formal or a priori.
The material to which a priori forms of the understanding were applied
was the sensuous content of the pure intuitions, Time and Space. This
content could not be _known_ by sense, but only by intellectual
function. But the understanding in the process of knowledge makes use
of the universal form of synthesis, the judgment; intellectual
function is essentially of the nature of judgment or the reduction of
a manifold to unity through a conception. The specific or type forms
of such function will, therefore, be expressed in judgments; and a
complete classification of the forms of judgments is the key by which
one may hope to discover the system of categories. Such a list of
judgments Kant thought he found in ordinary logic, and from it he drew
up his well-known scheme of the twelve categories. These forms are the
determinations of all objects of experience, for it is only through
them that the manifold of sense can be reduced to the unity of
consciousness, and thereby constituted experience. They are a priori
conditions, subjective in one sense, but objective as being universal,
necessary and constitutive of experience.

The table of logical judgments with corresponding categories is as
follows:--

Judgments. Categories.
Universal \ I. / Unity.
Particular > Of Quantity < Plurality.
Singular / \ Totality.

Affirmative \