but also bestow on them that precise colour, with which alone we are
acquainted. But afterwards having experience of the other colours of
violet, green, red, white, black, and of all the different compositions
of these, and finding a resemblance in the disposition of coloured
points, of which they are composed, we omit the peculiarities of colour,
as far as possible, and found an abstract idea merely on that disposition
of points, or manner of appearance, in which they agree. Nay even when
the resemblance is carryed beyond the objects of one sense, and the
impressions of touch are found to be Similar to those of sight in the
disposition of their parts; this does not hinder the abstract idea from
representing both, upon account of their resemblance. All abstract ideas
are really nothing but particular ones, 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