The article compares the understanding of self-knowledge of the mind in Tibetan Buddhism (in the schools of Mahamudra and Dzogchen) with the ancient, PlatonicChristian philosophy. It argues that in both traditions there are two aspects of the experience of self-knowledge: the impossibility of grasping the mind as an object and theceaseless, unavoidable awareness of the mind’s cognitive activity. The fi rst of those aspects is called by the Tibetan tradition “emptiness”, while the second – lucidity ofthe mind’s nature. In Gregory of Nyssa and Augustine of Hippo we can see a diff erence of accent in terms of the signifi cance of those two motifs, but it seems that bothphilosophers understand self-knowledge in a very similar way. Recognizing t...