Full Idea
Of the fact that everything is either asserted or denied truly, we must believe that it is the case.
Gist of Idea
Everything is either asserted or denied truly
Source
Aristotle (Posterior Analytics [c.327 BCE], 71a14)
Book Reference
Aristotle: 'Posterior Analytics (2nd ed)', ed/tr. Barnes,Jonathan [OUP 1993], p.1
A Reaction
Presumably this means that every assertion which could possibly be asserted must come out as either true or false. This will have to include any assertions with vague objects or predicates, and any universal assertions, and negative assertions.