l by a _vitium
subreptionis_, and to have deduced their pretended genealogies of such
ideas by means of a _petitio principii_--silently and stealthily
putting _into_ some step of their _leger-de-main_ process everything
that they would pretend to have extracted _from_ it. But, previously
to Kant, it is certain that all philosophers had left the origin of
these higher or transcendent ideas unexplained. Whence came they? In
the systems to which, Locke replies, they had been called _innate_ or
_connate_. These were the Cartesian systems. Cudworth, again, who
maintained certain '_immutable ideas_' of morality, had said nothing
about their origin; and Plato had supposed them to be reminiscences
from some higher mode of existence. Kant first attempted to assign
them an origin within the mind itself, though not in any Lockian
fashion of reflection upon sensible impressions. And this is doubtless
what he means by saying that he first had investigated the mind--that
is, he first for such a purpose.

Where, then, is it, in what act or function of the mind, that Kant
finds the matrix of these transcendent ideas? Simply in the logical
forms of the understanding. Every power exerts its agency under some
_laws_--that is, in the language of Kant, by certain _forms_. We leap
by certain laws--viz. of equilibrium, of muscular motion, of
gravitation. We dance by certain laws. So also we reason by certain
laws. These laws, or _formal_ principles, under a particular
condition, become the categories.

Here, then, is a short derivation, in a very few words, of those ideas
transcending sense, which all philosophy, the earliest, has been
unable to dispense with, and yet none could account for. Thus, for
example, every act of reasoning must, in the first place, express
itself in distinct propositions; that is, in such as contain a subject
(or that concerning which you affirm or deny something), a predicate
(that which you affirm or deny), and a copula, which connects them.
These propositions must have what is technically called, in logic, a
certain _quantity_, or compass (viz. must be universal, particular, or
singular); and again they must have what is called _quality_ (that is,
must be affirmative, or negative, or infinite): and thus arises a
ground for certain corresponding ideas, which are Kant's categories of
quantity and quality.

But, to take an illustration more appropriately from the very idea
which first aroused Kant to the sense o