Disjunctivism, Hallucination and Metacognition
Abstract
Perceptual experiences have been construed either as representational mental
states—Representationalism—or as direct mental relations to the external
world—Disjunctivism. Both conceptions are critical reactions to the so-called
‘Argument from Hallucination’, according to which perceptions cannot be about
the external world, since they are subjectively indiscriminable from other,
hallucinatory experiences, which are about sense-data ormind-dependent entities.
Representationalism agrees that perceptions and hallucinations share their most
specific mental kind, but accounts for hallucinations as misrepresentations of
the external world. According to Disjunctivism, the phenomenal character of
perceptions is exhausted by worldly objects and features, and thus must be
different from the phenomenal character of hallucinations. Disjunctivism claims
that subjective indiscriminability is not the result of a common experiential ground,
but is because of our inability to discriminate, from the inside, hallucinations from
perceptions. At first sight, Representationalism is more congenial to the way
cognitive science deals with perception. However, empirically oriented revisions
of Disjunctivism could be developed and tested by giving a metacognitive account
of hallucinations. Two versions of this account can be formulated, depending on
whether metacognition is understood as explicit metarepresentation or as implicit
monitoring of first-order informational states. The first version faces serious
objections, but the second is more promising, as it embodies a more realistic view
of perceptual phenomenology as having both sensory and affective aspects. Affectbased
phenomenology is constituted by various metacognitive feelings, such as
the feeling of being perceptually confronted with the world itself, rather than with
pictures or mere representations.