They, in every man's mouth, stand for the ideas he has, and which he would express by them.

A child having taken notice of nothing in the metal he hears called GOLD, but the bright shining yellow colour, he applies the word gold only to his own idea of that colour, and nothing else; and therefore calls the same colour in a peacock's tail gold.

Another that hath better observed, adds to shining yellow great weight: and then the sound gold, when he uses it, stands for a complex idea of a shining yellow and a very weighty substance.

Another adds to those qualities fusibility: and then the word gold signifies to him a body, bright, yellow, fusible, and very heavy.
Another adds malleability.

Each of these uses equally the word gold, when they have occasion to express the idea which they have applied it to: but it is evident that each can apply it only to his own idea; nor can he make it stand as a sign of such a complex idea as he has not.
4.