Full Idea
We wish to use the term 'true' in such a way that all the equivalences of the form (T) [i.e. X is true iff p] can be asserted, and we shall call a definition of truth 'adequate' if all these equivalences follow from it.
Gist of Idea
Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate'
Source
Alfred Tarski (The Semantic Conception of Truth [1944], 04)
Book Reference
'Semantics and the Philosophy of Language', ed/tr. Linsky,Leonard [University of Illinois 1972], p.16
A Reaction
The interpretation of Tarski's theory is difficult. From this I'm thinking that 'true' is simply being defined as 'assertible'. This is the status of each line in a logical proof, if there is a semantic dimension to the proof (and not mere syntax).
Related Ideas
Idea 19177 A definition of truth should be materially adequate and formally correct [Tarski]
Idea 19198 We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski]