 A different response to the clairvoyance problem is to concede that being the result of a reliable process is not sufficient for a belief to be prima facie justified. Rather, some further condition must be met. One version of this approach has been developed by Jack Lyons (2009, 2011) who argues that in order for a non-inferential belief to be justified, it must be the result of a “primal system”. Drawing on research in cognitive science, Lyons proposes that a primal system is any cognitive system that meets two conditions: (i) it is “inferentially opaque”—that is, its outputs are not the result of an introspectively accessible train of reasoning, (ii) it develops as a result of a combination of learning and innate constraints (2009: 144). For Lyons, our perceptual systems are paradigmatic examples of such primal systems.