This chapter concerns an idea shared by Parmenides and Sankara, that boundaries between human individuals, and between things, are not real but imposed by humans, and so 'epistemologically weak'. In contrast to Descartes, for whom the being of which he is certain belongs to a thinking substance or soul, they would both argue that being does not belong to any substance: rather, any entity proposed as the subject of being is produced by our superimposition of boundaries on being, which is fundamentally undivided. For them both it is impossible to know anything other than being, and therefore impossible to know boundaries and (consequently) the things separated by boundaries. This metaphysics of undivided being may facilitate experiencing lack of boundaries, yielding 'unshakenness' and invulnerability (Parmenides), compassion and liberation (Sankara).