This paper considers how Descartes's and Hume's sceptical challenges were appropriated by Christian Wolff and Johann Nicolaus Tetens specifically in the context of projects related to Kant's in the transcendental deduction. Wolff introduces Descartes's dream hypothesis as an obstacle to his account of the truth of propositions, or logical truth, which he identifies with the 'possibility' of empirical concepts. Tetens explicitly takes Hume's account of our idea of causality to be a challenge to the `reality' of transcendent concepts in general, (...) a challenge he addresses by locating the source of this concept in the understanding rather than in the imagination. After considering this background, I turn to Kant's deployment of apparently traditional sceptical concerns at the outset of the transcendental deduction and argue that he does not there intend to introduce a global sceptical challenge and, accordingly, that there are historical grounds for doubting that the transcendental deduction is intended as an anti-sceptical argument. (shrink)