o long as men thought that
real things subsisted without the mind, and that their knowledge was
only so far "real" as it was conformable to "real things," they could
not be certain that they had any real knowledge at all.

So long as we attribute a real existence to unthinking things, distinct
from their being perceived, it is not only impossible for us to know the
nature of any real unthinking being, but it is impossible for us even to
know that it exists. Hence it is that we see philosophers distrust their
senses, and doubt of the existence of heaven and earth, of everything
they see or feel. But all this doubtfulness, which so bewilders and
confounds the mind, vanishes if we annex a meaning to our words and do
not amuse ourselves with the terms "absolute," "external," "exist," and
such like, signifying we know not what. I can as well doubt of my own
being as of the being of those things which I perceive by sense; the
very existence of unthinking beings consists in their being perceived.

It were a mistake to think that what is here said derogates in the least
from the reality of things. The unthinking beings perceived by sense
exist in those unextended, indivisible substances, or spirits, which
act, think, and perceive them; whereas philosophers vulgarly hold that
the sensible qualities exist in an inert, extended, unperceiving
substance, which they call "matter," to which they attribute a natural
subsistence distinct from being perceived by any mind whatsoever, even
the eternal mind of the Creator.

As we have shown the doctrine of matter to have been the main support of
scepticism, so likewise upon the same foundation have been raised all
the impious schemes of atheism and irreligion. All these monstrous
systems have so visible and necessary a dependence on this supposed
material substance that, when this cornerstone is once removed, the
whole fabric cannot choose but fall to the ground.

On the same principle does not only fatalism but also idolatry depend in
all its varying forms. Did men but consider that the sun, moon, and
stars, and every other object of the senses, are only so many sensations
in their minds, which have no other existence but barely being
perceived, they would never fall down and worship their own ideas, but
rather address their homage to that Eternal Invisible Mind which
produces and sustains all things.

As in reading books, a wise man will choose to fix his thoughts on the
sense rather