The expression of the agreement and disagreement with the truth-possibilities of the elementary propositions expresses the truth-conditions of the proposition.
The proposition is the expression of its truth-conditions.
(Frege has therefore quite rightly put them at the beginning, as explaining the signs of his logical symbolism. Only Fregeās explanation of the truth-concept is false: if āthe trueā and āthe falseā were real objects and the arguments in ~ p , etc. , then the sense of ~ p would by no means be determined by Fregeās determination.)