— 574 —
A right joining, or separating of Signs; i.e. Ideas or Words.
      §2. Truth then seems to me, in the proper import of the Word, to
signify nothing but the joining or separating of Signs, as the Things
signified by them, do agree or disagree one with another. The joining or
separating of signs here meant is what by another name, we call
Proposition. So that Truth properly belongs only to Propositions:
whereof there are two sorts, viz. Mental and Verbal; as there are
two sorts of Signs commonly made use of, viz. Ideas and Words.
Locke Hum IV, 5, §2, p. 574