Abstract
Kant devotes to the problem of Cartesian skepticism a constant attention throughout his philosophical career. His first attempt to refute the skeptic goes back to the 1755 Nova Delucidatio, while other arguments, both in the pre-critical and in the critical period, follow one another in a rather erratic effort to remove the “scandal” of philosophy, that is, our inability to prove the existence of the external world beyond doubt. This on-going struggle against the skeptic does not end with the 1787 Second Edition of the Critique of Pure Reason wherein Kant presents his famous Refutation of Idealism. In a series of Reflexionen dating from the late 1780s to the early 1790 and named by Adickes “Reflexionen zum Idealismus,” Kant comes back to the problem that had captured his attention since 1755.