 Phenomenal consciousness has various epistemic markers: It gives rise to (at least the appearance of) an explanatory gap (see Levine 1983 and the entry on  consciousness),  it is susceptible to zombie thought experiments (see Chalmers 1996 and the entry on  zombies),  and it is susceptible to the knowledge argument (see Jackson 1982 and the entry Qualia: The Knowledge Argument).  These arguments usually focus on sensory phenomenal consciousness. For example, Levine’s central example is that of pain and Jackson’s is that of experiencing red. 