  The higher-order view is most obviously relevant to the meta-mental forms of consciousness, but some of its supporters take it to explain other types of consciousness as well, including the more subjective what it's like and qualitative types. One common strategy is to analyze qualia as mental features that are capable of occurring unconsciously; for example they might be explained as properties of inner states whose structured similarity relations given rise to beliefs about objective similarities in the world (Shoemaker 1975, 1990). Though unconscious qualia can play that functional role, there need be nothing that it is like to be in a state that has them (Nelkin 1989, Rosenthal 1991, 1997). According to the HO theorist, what-it's-likeness enters only when we become aware of that first-order state and its qualitative properties by having an appropriate meta-state directed at it.