2. Clear and obscure explained by sight.
The perception of the mind being most aptly explained by words relating
to the sight, we shall best understand what is meant by clear and obscure in our ideas, by reflecting on what we
call clear and obscure in the objects of sight. Light being that which discovers to us visible objects, we give the
name of obscure to that which is not placed in a light sufficient to discover minutely to us the figure and colours
which are observable in it, and which, in a better light, would be discernible. In like manner, our simple ideas are
clear, when they are such as the objects themselves from whence they were taken did or might, in a well-ordered
sensation or perception, present them. Whilst the memory retains them thus, and can produce them to the mind
whenever it has occasion to consider them, they are clear ideas. So far as they either want anything of the original
exactness, or have lost any of their first freshness, and are, as it were, faded or tarnished by time, so far are they
obscure. Complex ideas, as they are made up of simple ones, so they are clear, when the ideas that go to their
composition are clear, and the number and order of those simple ideas that are the ingredients of any complex one
is determinate and certain.