— 484 —
With this imperfection, they may serve for Civil, but not well for Philosophical use.
      §15. ’Tis true, as to civil and common Conversation, the general
names of Substances, regulated in their ordinary Signification by some
obvious Qualities, (as by the Shape and Figure in Things of known
seminal Propagation, and in other Substances, for the most part by
Colour, join’d with some other sensible Qualities,) do well enough,
to design the Things Men would be understood to speak of: And
so they usually conceive well enough the Substances meant by the
Word Gold, or Apple, to distinguish the one from the other. But in
Philosophical Enquiries and Debates, where general Truths are to be
establish’d, and Consequences drawn from Positions laid down,
there the precise signification of the names of Substances will be
found, not only not to be well established, but also very hard to be so.
For Example, he that shall make Malleableness, or a certain degree
of Fixedness, a part of his complex Idea of Gold, may make Propo-
sitions concerning Gold, and draw Consequences from them, that
will truly and clearly follow from Gold, taken in such a signification:
But yet such as another Man can never be forced to admit, nor be
convinced of their Truth, who makes not Malleableness, or the
same degree of Fixedness, part of that complex Idea, that the name
Gold, in his use of it, stands for.
Locke Hum III, 9, §15, p. 484