  According to Martin, given that this approach to perceptual experience needs to rely on this epistemic assumption, it carries more theoretical burdens than does the more “modest” disjunctivist approach. For when it comes to characterizing the notion of perceptual experience in general, the disjunctive approach emphasizes the limits of our powers of discrimination, rather than appealing to a substantive condition that an event must meet to be an experience, and in addition ascribing to us cognitive powers to recognize the presence of this substantive condition. So, according to Martin, the burden is really on the common element theorist, either to show that the extra epistemic commitment is one we should accept, or alternatively, to justify the claim that those conscious mental events that are introspectively indiscriminible from genuine perceptions but which lack the phenomenal properties of genuine perceptions should not be regarded as a perceptual experiences. This argument does not purport to show that the common element view is wrong, but rather to show that the default position should be that of the disjunctivist.