Cardinal Bessarion (1408–1472), in the second chapter of the first book of his influential work In calumniatorem Platonis, attempted to reply to Georgios Trapezuntios’ (1396–1474) criticism against Plato in the Comparatio Philosophorum Platonis et Aristotelis. Bessarion investigates why the Athenian philosopher maintained, in several dialogues, that the sacred truths should not be communicated to the general public and argued in favor of the value of oral transmission of knowledge, largely based on his theory about the cognitive processes. Recently, Fr. Bessarion Kouotsis has argued that Cardinal Bessarion’s reasoning draws primarily on the “Disciplina Arcani”, i.e., the rule of secrecy, which was an established practice of the Early Christian Church, aimed at protecting and preserving the core elements of the religion from outsiders. While I find Kouotsis’ approach interesting and thought-provoking—for instance, the idea that Bessarion’s argumentation was likely influenced by Eastern Christian views on the rule of secrecy—I intend, first of all, to discuss why Bessarion did not explicitly mention it. Moreover, I would like to argue that Bessarion’s good knowledge of the long Platonic tradition and Eastern mysticism, encompassing both pagan and Christian elements, should also be considered a significant source. Furthermore, I would like to question Kouotsis’ implicit argument that Bessarion’s views were dominated by his training in Orthodox theology and discuss the possibility that Pletho’s (1355–1454) teaching was the obvious influence for Bessarion’s defense of secrecy. After all, we should bear in mind that Anastos has already pointed out Pletho’s reverence for the rule of secrecy. Finally, I would like to support that Bessarion, in the specific text, focused predominantly on the epistemological and cognitive aspects of oral teaching, resorting to the rule of secrecy only to enhance his views