Elements of the philosophy of the human mind. By Dugald Stewart. Rev. and abridged, with critical and explanatory notes, for the use of colleges and schools. By Francis Bowen ...

TEE INFLUENCE OF CASUAL ASSOCIATION'S. 211
line, and we apply the same language to both subjects. We
speak of a long and short time, as well as of a long and short
distance; and we are not conscious of any metaphor in doing
so. Nay, so very perfect does the analogy appear to us, that
Boscovich mentions it as a curious circumstance, that extension
should have three dimensions, and duration only one.
This apprehended analogy seems to be founded wholly on an
association between the ideas of space and of time, arising from
our always measuring the one of these quantities by the other.
Wve measure time by motion, and motion by extension. In an
hour, the hand of the clock moves over a certain space; in two
hours, over double the space; and so on. Hence the ideas of
space and of time become very intimately united, and we apply
to the latter the words long and short, before and after, in the
same manner as to the former.
The apprehended analogy between the relation which the
different notes in the scale of music bear to each other, and the
relation of superiority and inferiority, in respect of position,
among material objects, arises also from an accidental association of ideas.
What this association is founded upon, I shall not take upon
me to determine; but that it is the effect of accident, appears
clearly from this, that it has not only been confined to particular
who has not been very familiarly conversant with philosophical inquiries. -
I find, at least, that such is the notion which most readily presents itself
to my own mind.
Nor is this reference of the sensation, or appearance, of color to an
external olject, a fact altogether singular in our constitution. It is extremely analogous to the reference, which we always make, of the sensations
of touch to those parts of the body where the exciting causes of the sensations exist. If I strike my hand against a hard object, I naturally say,
that I feel pain in my hand. The philosophical truth is, that I perceive
the cause of the pain to be applied to that part of my body. The sensation itself I cannot refer, in point of place, to the hand, without conceiving the soul to be spread over the body by diffusion.
A still more striking analogy to the fact under our consideration, occurs
in those sensations of touch which we refer to a place beyond the limits of
the body; as in the case of pain felt in an amputated limb.