this a direct repugnancy, and altogether inconceivable?

18. THE EXISTENCE OF EXTERNAL BODIES WANTS PROOF.--But, though it
were possible that solid, figured, movable substances may exist
without the mind, corresponding to the ideas we have of bodies,
yet HOW IS IT POSSIBLE FOR US TO KNOW THIS? Either we must know it by
sense or by reason. As for our senses, by them we have the knowledge ONLY
OF OUR SENSATIONS, ideas, or those things that are immediately perceived
by sense, call them what you will: but they do not inform us that things
exist without the mind, or unperceived, like to those which are
perceived. This the materialists themselves acknowledge. It remains
therefore that if we have any knowledge at all of external things, it
must be by REASON, inferring their existence from what is immediately
perceived by sense. But what reason can induce us to believe the
existence of bodies without the mind, from what we perceive, since the
very patrons of Matter themselves do not pretend there is ANY NECESSARY
CONNEXION BETWIXT THEM AND OUR IDEAS? I say it is granted on all hands
(and what happens in dreams, phrensies, and the like, puts it beyond
dispute) that IT IS POSSIBLE WE MIGHT BE AFFECTED WITH ALL THE IDEAS WE
HAVE NOW, THOUGH THERE WERE NO BODIES EXISTING WITHOUT RESEMBLING THEM.
Hence, it is evident the supposition of external bodies is not necessary
for the producing our ideas; since it is granted they are produced
sometimes, and might possibly be produced always in the same order, we
see them in at present, without their concurrence.

19. THE EXISTENCE OF EXTERNAL BODIES AFFORDS NO EXPLICATION OF THE MANNER
IN WHICH OUR IDEAS ARE PROCUCED.--But, though we might possibly
have all our sensations without them, yet perhaps it may be thought
EASIER to conceive and explain the MANNER of their production,
by supposing external bodies in their likeness rather than otherwise;