n experienced to
coexist with great magnitude. But when it is caused by the interposition
of an opaque sensible body, this circumstance alters the case, so that a
faint appearance this way caused doth not suggest greater magnitude,
because it hath not been experienced to coexist with it.
73. Faintness, as well as all other ideas or perceptions which suggest
magnitude or distance, doth it in the same way that words suggest the
notions to which they are annexed. Now, it is known a word pronounced
with certain circumstances, or in a certain context with other words,
hath not always the same import and signification that it hath when
pronounced in some other circumstances or different context of words. The
very same visible appearance as to faintness and all other respects, if
placed on high, shall not suggest the same magnitude that it would if it
were seen at an equal distance on a level with the eye. The reason
whereof is that we are rarely accustomed to view objects at a great
height; our concerns lie among things situated rather before than above
us, and accordingly our eyes are not placed on the top of our heads, but
in such a position as is most convenient for us to see distant objects
standing in our way. And this situation of them being a circumstance
which usually attends the vision of distant objects, we may from hence
account for (what is commonly observed) an object's appearing of
different magnitude, even with respect to its horizontal extension, on
the top of a steeple, for example, an hundred feet high to one standing
below, from what it would if placed at an hundred feet distance on a
level with his eye. For it hath been shown that the judgment we make on
the magnitude of a thing depends not on the visible appearance alone, but
also on divers other circumstances, any one of which being omitted or
varied may suffice to make some alteration in our judgment. Hence, the
circumstances of viewing a distant object in such a situation as is
usual, and suits with the ordinary posture of the head and eyes being
omitted, and instead thereof a different situation of the object, which
requires a different posture of the head taking place, it is not to be
wondered at if the magnitude be judged different: but it will be demanded
why an high object should constantly appear less than an equidistant low
object of the same dimensions, for so it is observed to be: it may indeed
be granted that the variation of some circumstanc
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