MATTER after what has been said, I could instance several of those errors
and difficulties (not to mention impieties) which have sprung from that
tenet. It has occasioned numberless controversies and disputes in
philosophy, and not a few of far greater moment in religion. But I shall
not enter into the detail of them in this place, as well because I think
arguments A POSTERIORI are unnecessary for confirming what has been, if I
mistake not, sufficiently demonstrated A PRIORI, as because I shall
hereafter find occasion to speak somewhat of them.

22. I am afraid I have given cause to think I am needlessly prolix in
handling this subject. For, to what purpose is it to dilate on that which
may be demonstrated with the utmost evidence in a line or two, to any one
that is capable of the least reflexion? It is but looking into your own
thoughts, and so trying whether you can conceive it possible for a sound,
or figure, or motion, or colour to exist without the mind or unperceived.
This easy trial may perhaps make you see that what you contend for is a
downright contradiction. Insomuch that I am content to put the whole upon
this issue:--If you can but CONCEIVE it possible for one extended movable
substance, or, in general, for any one idea, or anything like an idea, to
exist otherwise than in a mind perceiving it, I shall readily give up the
cause. And, as for all that COMPAGES of external bodies you contend for,
I shall grant you its existence, THOUGH (1.) YOU CANNOT EITHER GIVE ME ANY
REASON WHY YOU BELIEVE IT EXISTS [Vide sect. lviii.], OR (2.) ASSIGN ANY
USE TO IT WHEN IT IS SUPPOSED TO EXIST [Vide sect. lx.]. I say, the bare
possibility of your opinions being true shall pass for an argument that
it is so. [Note: i.e. although your argument be deficient in the two
requisites of an hypothesis.--Ed.]

23. But, say you, surely there is nothing easier than for me to imagine
trees, for instance, in a park, or books existing in a closet, and nobody