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 belongs to
extension, and is what distinguishes it from duration. Now as time is
composed of parts, that are not coexistent: an unchangeable object, since
it produces none but coexistent impressions, produces none that can give
us the idea of time; and consequently that idea must be derived from a
succession of changeable objects, and time in its first appearance can
never be severed from such a succession.

Having therefore found, that time in its first appearance to the mind is
always conjoined with a succession of changeable objects, and that
otherwise it can never fall under our notice, we must now examine whether