Both Sidgwick’s and Kant’s examples rely on non-ideal publics. Admittedly they do so in different manners. Whereas Kant’s ideal public apparently sticks to the role of a judge, Sidgwick’s ideal community of utilitarians is taken as a set of actors whose understanding of the rules is likely to affect their actual behavior. However, the reasons justifying secrecy in the examples each of them gives are of a very different nature. For Sidgwick’s illustrations do not necessarily involve power relation problems. Instead, they highlight motivational and cognitive dimensions. For our purposes, what matters is that, whereas the examples given by Sidgwick properly illustrate the logic of his argument, those provided by Kant do not enlighten us much further, for the idea of purpose frustration (or “self-frustration”) mobilized in the rebellion and secession cases is not applicable once we shift to an ideal public. Therefore, we shall now rely on four examples distinct from those mentioned by Kant in order to ascertain the meaning and implications that could be attached to the Kantian test.