 This would fit with the model of schizotypy as essentially a normal dimension of personality, and might help to explain why the proneness to anomalous perceptual experiences has apparently not been ‘weeded out’ by the process of natural selection.Apparitional experiences also have implications for the philosophy of perception.The occurrence of hallucinations, that is, perceptual experiences 'having the character of sense perception, but without relevant or adequate sensory stimulation [...]', have long been one of the standard objections to the philosophical theory of direct realism.