mental powers ill applied which the
world has ever witnessed--as one continuous comment upon this text, the
necessity of adhering to careful, honest observation of mental
phenomena, however homely may be the results of such observation, and
the astounding conclusions to which a train of thought rigidly pursued
may conduct us, if, at its very point of departure, it has broken loose
from this the first obligation of philosophy. The whole career of German
speculation manifests a disregard of some of those fundamental
principles of human belief, which, according to M. Cousin himself, it is
the peculiar merit of the Scotch to have seized and held with tenacity.

These observations we will illustrate by a glance at the theories
propounded on the great subject of perception--on the nature of our
knowledge of the external world, this _visible and tangible_ creation.

To a plain unsophisticated man, a stranger to the subtleties of
metaphysical thought, it appears quite inconceivable, when he is told
that the existence of the visible and palpable scene before him should
be converted into a problem of apparently invincible difficulty. Yet so
it is. The metaphysician first carries off in triumph what are called
its secondary qualities, as colour and heat, proving them to be no
qualities of matter, but of mind, or the sensitive being. He next
assails what had been pronounced to be its primary or essential
qualities; the dark tangible mass that he had left behind is not
suffered to retain its inert existence; extension, the power to fill
space or resist pressure, what are these, he asks, but our own
sensations or remembered sensations of touch, which have got associated,
embodied together, agglomerated round some occult cause? What, after
all, he exclaims, do we know of matter but as a _something_ which
possesses certain influences over _us_?--a something which is utterly
unrepresented to us by the senses. And now this word "substance," which
formerly expressed a thing so well known, and every moment handled and
looked at, is transformed to an invisible, intangible, imperceptible
substratum--an unknown upholder of certain qualities, or, in more exact
language, an unseen power clothing itself in _our_ attributes--an
existence far more resembling what is popularly understood by spirit
than by matter. At length, even this unseen substratum is drawn within
the world of thought, and becomes itself mere thought. There is _no_
matter, the