e mind.

"But for the fuller clearing of this point, it may be worth
while to consider how it is that we perceive distance and
things placed at a distance by sight. For that we should in
truth see external space and bodies actually existing in it,
some nearer, others further off, seems to carry with it some
opposition to what hath been said of their existing nowhere
without the mind. The consideration of this difficulty it
was that gave birth to my 'Essay towards the New Theory of
Vision,' which was published not long since, wherein it is
shown that distance, or outness, is neither immediately of
itself perceived by sight, nor yet apprehended, or judged
of, by lines and angles or anything that hath any necessary
connection with it; but that it is only suggested to our
thoughts by certain visible ideas and sensations attending
vision, which, in their own nature, have no manner of
similitude or relation either with distance, or with things
placed at a distance; but by a connection taught us by
experience, they come to signify and suggest them to us, after
the same manner that words of any language suggest the ideas
they are made to stand for; insomuch that a man born blind and
afterwards made to see, would not, at first sight, think the
things he saw to be without his mind or at any distance from
him."

The key-note of the Essay to which Berkeley refers in this passage is
to be found in an italicized paragraph of section 127:--

"_The extensions; figures, and motions perceived by sight are
specifically distinct from the ideas of touch called by the
same names; nor is there any such thing as an idea, or kind of
idea, common to both senses_."

It will be observed that this proposition expressly declares that
extension, figure, and motion, and consequently distance, are
immediately perceived by sight as well as by touch; but that visual
distance, extension, figure, and motion, are totally different in
quality from the ideas of the same name obtained through the sense
of touch. And other passages leave no doubt that such was Berkeley's
meaning. Thus in the 112th section of the same Essay, he carefully
defines the two kinds of distance, one visual, the other tangible:--

"By the distance between any two points nothing more is meant
than the number of intermediate points. If the given points
are visibl