I will not here trouble myself to prove that all terms are not
definable, from that progress IN INFINITUM, which it will visibly lead
us into, if we should allow that all names could be defined. For, if the
terms of one definition were still to be defined by another, where at
last should we stop? But I shall, from the nature of our ideas, and the
signification of our words, show WHY SOME NAMES CAN, AND OTHERS CANNOT
BE DEFINED; and WHICH THEY ARE.


6. What a Definition is.

I think it is agreed, that a DEFINITION is nothing else but THE SHOWING
THE MEANING OF ONE WORD BY SEVERAL OTHER NOT SYNONYMOUS TERMS. The
meaning of words being only the ideas they are made to stand for by him
that uses them, the meaning of any term is then showed, or the word is
defined, when, by other words, the idea it is made the sign of, and
annexed to, in the mind of the speaker, is as it were represented, or
set before the view of another; and thus its signification ascertained.
This is the only use and end of definitions; and therefore the only
measure of what is, or is not a good definition.


7. Simple Ideas, why undefinable.

This being premised, I say that the NAMES OF SIMPLE IDEAS, AND THOSE
ONLY, ARE INCAPABLE OF BEING DEFINED. The reason whereof is this, That
the several terms of a definition, signifying several ideas, they can
all together by no means represent an idea which has no composition
at all: and therefore a definition, which is properly nothing but the