be evident to whoever considers what hath been already said, and what
follows.

54. It hath been shown there are two sorts of objects apprehended by
sight; each whereof hath its distinct magnitude, or extension. The one,
properly tangible, i.e. to be perceived and measured by touch, and not
immediately falling under the sense of seeing: the other, properly and
immediately visible, by mediation of which the former is brought in view.
Each of these magnitudes are greater or lesser, according as they contain
in them more or fewer points, they being made up of points or minimums.
For, whatever may be said of extension in abtract, it is certain sensible
extension is not infinitely divisible. There is a MINIMUM TANGIBILE and a
MINIMUM VISIBILE, beyond which sense cannot perceive. This everyone's
experience will inform him.

55. The magnitude of the object which exists without the mind, and is at
a distance, continues always invariably the same: but the visible object
still changing as you approach to, or recede from, the tangible object,
it hath no fixed and determinate greatness. Whenever, therefore, we speak
of the magnitude of anything, for instance a tree or a house, we must
mean the tangible magnitude, otherwise there can be nothing steady and
free from ambiguity spoken of it. But though the tangible and visible
magnitude in truth belong to two distinct objects: I shall nevertheless
(especially since those objects are called by the same name, and are
observed to coexist), to avoid tediousness and singularity of speech,
sometimes speak of them as belonging to one and the same thing.

56. Now in order to discover by what means the magnitude of tangible
objects is perceived by sight. I need only reflect on what passes in my
own mind, and observe what those things be which introduce the ideas of