  Fish (2008 and 2009) proposes a rather different disjunctivist account of hallucination, which applies to all hallucinations, including causally matching hallucinations. Fish offers what he calls a minimal, but positive, story about hallucination. According to Fish, a mental state that may be intrinsically quite different from a veridical perception might come to be mistaken for a veridical perception and therein acquire the status of hallucination. Fish thinks that the demand for a more substantial intrinsic characterisation of hallucination is misguided, but that the following positive story can be told. The indistinguishability of hallucination from veridical perception is grounded in the similarity of their effects. A hallucination of an x is a mental state that, whilst not being a veridical perception of an x, nevertheless comes to have effects that are sufficiently similar to those a veridical perception would have had. If the subject is conceptually sophisticated these effects will include higher-order beliefs about seeing an x, or seeming to see an x.  If the subject is not sophisticated enough to have such beliefs at all, the effects will be solely behavioural.