Online research in philosophy

Merker’s definition of consciousness excludes self-reflective thought, making his proposal for decorticate consciousness not particularly groundbreaking. He suggests that brainstem sites are neglected in current theories of consciousness. This is so because broader definitions of consciousness are used. Split-brain data show that the cortex is important for full-blown consciousness; also, behaviors exhibited by hydranencephaly patients and decorticated rats do not seem to require reflective consciousness.

Consider the conscious states of a single subject at a time. Arguably, split-brain cases show that such states need not be jointly accessible. It is less clear that these cases also show that such states need not be jointly experienced. Michael Tye (2004) argues split-brain cases do have that implication, and Timothy Bayne and David Chalmers (2003) argue that they do not. I will develop two objections to Tye’s arguments. First, an analogy to blindsight on which he relies is questionable. Second, even if his analogy succeeds, it shows only that a single person can simultaneously have two separate sets of phenomenally conscious mental states. That result fails to undermine the phenomenalunity thesis that Bayne and Chalmers defend, on which phenomenal consciousness is necessarily unified.

In "Consciousness Explained," Dennett (1991) denies that split-brain humans have double consciousness: he describes the experiments as "anecdotal." In attempting to replace the Cartesian Theatre of the Mind" with his own "Multiple Drafts" view of consciousness, Dennett rejects the notion of the mind as a countable thing in favour of its being a mere "abstraction." His criticisms of the standard interpretation of the split-brain data are analyzed here and each is found to be open to objections. There exist people who have survived left ["dominant"] cerebral hemispherectomy; by Dennett's criteria, they would not have minds.

Abstract: This paper argues for a distinction between possession of a unified consciousness and possession of a single stream of consciousness. Although the distinction has widespread applicability in discussions of the structure of consciousness and of pathologies of conscious experience, I will illustrate its importance primarily using the debate about consciousness in split-brain subjects, suggesting that those who have argued that split-brain subjects have two streams of consciousness apiece and those who have argued that they have a unified consciousness may both be right.

Some argue that split-brain cases undermine the thesis that phenomenal consciousness is necessarily unified. This paper defends the phenomenal unity thesis against Michael Tye's (2003 ) version of that argument. Two problems are identified. First, his argument relies on a questionable analysis of the split-brain data. Second, his analysis leads to the view that in experimental situations split-brain patients are not single subjects – a result that would render the analysis harmless to the phenomenal unity thesis.

Foundations. The phenomenal field ; Phenomenal unity : mereology ; Phenomenal unity : closure -- Consciousness unified?. Motivating the unity thesis ; How to evaluate the unity thesis ; Fragments of consciousness? ; Anosognosia, schizophrenia, and multiplicity ; Hypnosis ; The split-brain syndrome -- Implications. The quilt of consciousness ; The body ; The self.

In Consciousness and persons, Michael Tye (Tye, M. (2003). Consciousness and persons. Cambridge, MA: MIT Press.) develops and defends a novel approach to the unity of consciousness. Rather than thinking of the unity of consciousness as involving phenomenal relations between distinct experiences, as standard accounts do, Tye argues that we should regard the unity of consciousness as involving relations between the contents of consciousness. Having developed an account of what it is for consciousness to be unified, Tye goes on to apply his account of the unity of consciousness to the split-brain syndrome. I provide a critical evaluation of Tye's account of the unity of consciousness and the split-brain syndrome.

In Consciousness and persons, Michael Tye (Tye, M. (2003). Consciousness and persons. Cambridge, MA: MIT Press.) develops and defends a novel approach to the unity of consciousness. Rather than thinking of the unity of consciousness as involving phenomenal relations between distinct experiences, as standard accounts do, Tye argues that we should regard the unity of consciousness as involving relations between the contents of consciousness. Having developed an account of what it is for consciousness to be unified, Tye goes on to apply his account of the unity of consciousness to the split-brain syndrome. I provide a critical evaluation of Tye's account of the unity of consciousness and the split-brain syndrome.