If the initial cognition is not credited with the intrinsic capacity for conferring justification, no further cognition could bestow that capacity either—unless the further cognition is itself credited with immediately having that capacity.
A normative enterprise that tells us how we ought to reason from evidence and how we ought to justify our beliefs, as distinct from merely describing how we do reason or justify beliefs
immediately(as used in the logical chain of reasoning)
In this context, directly or without needing help from anything else.
intrinsic capacity(as used in philosophy of knowledge)
An ability or power that something has built into its own nature, rather than getting it from something else.
justification(Third condition of the tripartite account of knowledge)
The condition on a knower's belief that excludes mere luck — the belief must be held in a way that is appropriate or warranted, not merely accidentally correct.
The locus classicus for Kumārila’s argument here is verse 47 of the codanā sūtra chapter of the Ślokavārttika: “It should be understood that all pramāṇas’ have the property of being pramāṇas intrinsically; for a capacity not already existing by itself (svataḥ) cannot be produced by anything else.” (All of the passages given here from Kumārila and his commentators can be found in Arnold 2005, 57–114.) The argument Kumārila concisely expresses here in verse form is straightforward but compelling