not to be trusted, so neither can it be convicted of falsehood.
We cannot launch ourselves out of our own nature; we _cannot test_ our
own faculties of cognition. This could only be done by some superior
intelligence who could survey apart the object and the percipient
subject.

We _may be_ deceived in believing that we ourselves exist--that there is
any permanent being we call ourselves--but there is no demonstrating
that we _are_ so deceived. The two cases are strictly analogous. We have
just the same proof of the existence of the external object as of the
thinking and percipient subject. The very first sensation or perception
we experience brings with it instantaneously the two correlates, object
and subject; they are made known in the same act or feeling; they are
made known the one by means of the other--for unless through the means
of the antagonist idea of object we should not have that of subject, nor
_vice versa_. In our judgment, therefore, there is as little philosophy
in denying the external existence of matter as the internal existence of
mind. The two ideas, as we have said, rise instantaneously,
synchronously, and are in such manner correlates that it is only by the
presence of the one that the other reveals itself.[6]

When Kant advanced from doubting of the _objective_ truth of our
knowledge of space, to deciding against it--to asserting that it was
purely _subjective_--he was exceeding the limits of the human faculties,
and offering a mere dogmatism which can never be brought to any test
whatever. He was asking us to judge of the trustworthiness of our
faculties of cognition--by what?--by our faculties of cognition. He was
elevating what is at best a strange suspicion, a mere _guess_, into a
doctrine.

And the whole superstructure of the systems of idealism which his German
followers have reared, rests upon this guess!

Kant left nothing of the material world but an indescribable _noumenon_,
which did not even exist in space. Of course the categories of
Aristotle, classifying as they did those relations which constitute our
knowledge of this world, were converted by him into mere forms of the
_understanding_, moulding the given products of the _sensibility_.
Certain other regulative modes of thought predominating, in their turn,
over the products of the _understanding_, he called ideas of the _pure
reason_.

His successor, Fichte, it will be seen, advanced but little further when
he pronounced fo