 In the Pramāṇa-siddhi-chapter of the Pramāṇa-vārttika, Dharmakīrti argues that past lives exist. We can know this because of the authority of the Buddha and we have reason to accept his authority because of his infinite compassion. This compassion can only be the result of practice over many life times [PV 36]. The Lokāyata philosophers argue that cognitions require the support of a body and therefore cease to exist when the body ceases to exist. Dharmakīrti objects to this by arguing that mental cognitions do not derive from any physical support [PV 49]. Śāntarakṣita and Kamalaśīla state that the relationship between the support and what is supported can be analyzed either as a causal relationship or as the relationship between an object and its capacity [TS and TSP 1858–1859]. In this respect they do not deviate from Dharmakīrti who rejects this position of the Lokāyata philosophers by arguing that the body could be neither the cause of cognition nor could it have the capacity of cognition. Franco explains Dharmakīrti’s argument in the following way: