sent the tangible square, but then it is not
because it is liker, or more of a species with it, but because the
visible square contains in it several distinct parts, whereby to mark the
several distinct corresponding parts of a tangible square, whereas the
visible circle doth not. The square perceived by touch hath four
distinct, equal sides, so also hath it four distinct equal angles. It is
therefore necessary that the visible figure which shall be most proper to
mark it contain four distinct equal parts corresponding to the four sides
of the tangible square, as likewise four other distinct and equal parts
whereby to denote the four equal angles of the tangible square. And
accordingly we see the visible figures contain in them distinct visible
parts, answering to the distinct tangible parts of the figures signified
or suggested by them.

143. But it will not hence follow that any visible figure is like unto,
or of the same species with, its corresponding tangible figure, unless it
be also shown that not only the number but also the kind of the parts be
the same in both. To illustrate this, I observe that visible figures
represent tangible figures much after the same manner that written words
do sounds. Now, in this respect words are not arbitrary, it not being
indifferent what written word stands for any sound: but it is requisite
that each word contain in it so many distinct characters as there are
variations in the sound it stands for. Thus the single letter A is proper
to mark one simple uniform sound; and the word ADULTERY is accommodated
to represent the sound annexed to it, in the formation whereof there
being eight different collisions or modifications of the air by the
organs of speech, each of which produces a difference of sound, it was
fit the word representing it should consist of as many distinct
characters, thereby to mark each particular difference or part of the
whole sound. And yet nobody, I presume, will say the single letter a, or
the word ADULTERY, are like unto, or of the same species with, the
respective sounds by them represented. It is indeed arbitrary that, in
general, letters of any language represent sounds at all: but when that
is once agreed, it is not arbitrary what combination of letters shall
represent this or that particular sound. I leave this with the reader to
pursue, and apply it in his own thoughts.

144. It must be confessed that we are not so apt to confound other signs
with the