14. This, if not heeded, causes confusion in our arguings.
He that thinks he has a distinct idea of the figure of a
chiliaedron, let him for trial sake take another parcel of the same uniform matter, viz., gold or wax of an equal
bulk, and make it into a figure of 999 sides. He will, I doubt not, be able to distinguish these two ideas one from
another, by the number of sides; and reason and argue distinctly about them, whilst he keeps his thoughts and
reasoning to that part only of these ideas which is contained in their numbers; as that the sides of the one could be
divided into two equal numbers, and of the others not, etc. But when he goes about to distinguish them by their
figure, he will there be presently at a loss, and not be able, I think, to frame in his mind two ideas, one of them
distinct from the other, by the bare figure of these two pieces of gold; as he could, if the same parcels of gold were
made one into a cube, the other a figure of five sides. In which incomplete ideas, we are very apt to impose on
ourselves, and wrangle with others, especially where they have particular and familiar names. For, being satisfied
in that part of the idea which we have clear; and the name which is familiar to us, being applied to the whole,
containing that part also which is imperfect and obscure, we are apt to use it for that confused part, and draw
deductions from it in the obscure part of its signification, as confidently as we do from the other.
