nes, considered in
a certain light; but being annexed to general terms, they are able to
represent a vast variety, and to comprehend objects, which, as they are
alike in some particulars, are in others vastly wide of each other.

The idea of time, being derived from the succession of our perceptions
of every kind, ideas as well as impressions, and impressions of
reflection as well as of sensations will afford us an instance of an
abstract idea, which comprehends a still greater variety than that of
space, and yet is represented in the fancy by some particular individual
idea of a determinate quantity and quality.

As it is from the disposition of visible and tangible objects we receive
the idea of space, so from the succession of ideas and impressions we
form the idea of time, nor is it possible for time alone ever to make
its appearance, or be taken notice of by the mind. A man in a sound
sleep, or strongly occupyed with one thought, is insensible of time;
and according as his perceptions succeed each other with greater or
less rapidity, the same duration appears longer or shorter to his
imagination. It has been remarked by a great philosopher, that our
perceptions have certain bounds in this particular, which are fixed by
the original nature and constitution of the mind, and beyond which no
influence of external objects on the senses is ever able to hasten or
retard our thought. If you wheel about a burning coal with rapidity, it
will present to the senses an image of a circle of fire; nor will there
seem to be any interval of time betwixt its revolutions; meerly because
it is impossible for our perceptions to succeed each other with the same
rapidity, that motion may be communicated to external objects. Wherever
we have no successive perceptions, we have no notion of time, even
though there be a real succession in the objects. From these phenomena,
as well as from many others, we may conclude, that time cannot make
its appearance to the mind, either alone, or attended with a steady
unchangeable object, but is always discovered some PERCEIVABLE
succession of changeable objects.

To confirm this we may add the following argument, which to me seems
perfectly decisive and convincing. It is evident, that time or duration
consists of different parts: For otherwise we coued not conceive a
longer or shorter duration. It is also evident, that these parts are not
co-existent: For that quality of the co-existence of parts bel