Debates surrounding the question of truth mainly concern the disagreement between inflationists and deflationists, the first seeking to understand the underlying nature of the property of being true, the latter denying that this property has a philosophically interesting nature at all. In recent decades a number of “moderate” deflationists have formulated this latter thesis by asserting that truth is not a substantial property. How should we understand the meaning of this statement ? In this article, the author sets himself the task of evaluating the various analyses of unsubstantiality that have been put forward to grasp what is meant by the distinctive position of moderate deflationism. We will conclude that none of them, in their present form, can suit the ends of deflationism.