Truth-telling is a project that is both gripping and problematic for Rousseau, as he is both captured by an ideal of telling as complete, undistorted discernment, documentation and communication, and also haunted by the fear that telling can never be this innocent. For Rousseau, as for Kant, telling does not leave the told untouched; rather, telling gives us a type of contact with objects that is marked and mediated by the process of telling itself, and hence the possibility of immediately grasping objects through telling is forever lost to us. The drive to capture things in themselves, which originates, according to Kant, in a formal principle of reason, shows up in Rousseau's writings as a nostalgia that governs and animates inquiry. I will read Rousseau, and the traumas of truth-telling he articulates, as important pretexts for Kant's critical epistemology. Rousseau discloses tensions that infect his truth-telling practices. Kant seeks to neutralize these tensions, not by dissolving them, but rather by translating them into the terms of transcendental philosophy and thus showing how they can be defused and rendered harmless in their empirical form, so as to secure the possibility of proper truth-telling.