It is therefore certain, that the imagination reaches a minimum, and may
raise up to itself an idea, of which it cannot conceive any sub-division,
and which cannot be diminished without a total annihilation. When you
tell me of the thousandth and ten thousandth part of a grain of sand, I
have a, distinct idea of these numbers and of their different
proportions; but the images, which I form in my mind to represent the
things themselves, are nothing different from each other, nor inferior to
that image, by which I represent the grain of sand itself, which is
supposed so vastly to exceed them. What consists of parts is
distinguishable into them, and what is distinguishable is separable. But
whatever we may imagine of the thing, the idea of a grain of sand is not
distinguishable, nor separable into twenty, much less into a thousand,
ten thousand, or an infinite number of different ideas.

It is the same case with the impressions of the senses as with the ideas
of the imagination. Put a spot of ink upon paper, fix your eye upon that
spot, and retire to such a distance, that, at last you lose sight of it;
it is plain, that the moment before it vanished the image or impression
was perfectly indivisible. It is not for want of rays of light striking on
our eyes, that the minute parts of distant bodies convey not any sensible
impression; but because they are removed beyond that distance, at which
their impressions were reduced to a minimum, and were incapable of any
farther diminution. A microscope or telescope, which renders them
visible, produces not any new rays of light, but only spreads those,
which always flowed from them; and by that means both gives parts to
impressions, which to the naked eye appear simple and uncompounded, and
advances to a minimum, what was formerly imperceptible.

We may hence discover the error of the common opinion, that the capacity