Split brains that result in two simultaneous streams of consciousness cut off from each other are wrongly held to be grounds for doubting the existence of the divinely created soul. The mistake is based on two related errors: first, a failure to appreciate the soul's dependence upon neurological functioning; second, a fallacious belief that if the soul is simple, i.e. without parts, then there must be a unity to its thought, all of its thoughts being potentially accessible to reflection or (...) even unreflective causal interactions. But a soul theorist can allow neurological events to keep some conscious thoughts unavailable to others. (shrink)

Many experimental findings with split-brain subjects intuitively suggest that each such subject has two minds. The conceptual and empirical basis of this duality intuition has never been fully articulated. This article fills that gap, by offering a reconstruction of early neuropsychological literature on the split-brain phenomenon. According to that work, the hemispheres operate independently of each other insofar as they interact via the mediation of effection and transduction—via behavior and sensation, essentially. This is how your mind and my mind interact (...) with each other, however, giving rise to the intuition that a split-brain subject has two minds. (shrink)

In this paper I will provide a hylomorphic critique of Jeff McMahan’s “An Alternative to Brain Death.” I will evaluate three puzzles—the dicephalus, the braintransplant, and the split-brain phenomenon—proposed by McMahan which allow him to deny that a human being is identical to an organism. I will contend thatMcMahan’s solution entails counterintuitive consequences that pose problems to organ transplant cases. A Thomistic hylomorphic metaphysics not only avoids these unwelcome consequences and provides solutions to the three puzzles but in doing so (...) allows for an alternative definition of death. Since McMahan has constructed his definition of death around his own metaphysics, alternative metaphysics, in this case a hylomorphic metaphysics, allow for an alternative definition of death. (shrink)

In biology, man is an object of research; therefore the question might be asked whether inspirations can go from biological data to the reflections on the mind-matter relation in man. The social aspect of man, as treated by sociobiology, is left out of consideration. The knowledge that man is mind, or has a mind, is no result of biological research. It is a datum from philosophy. The biologist, however, is living in a culture which knows about the mental character of (...) man, and this is incorporated in his investigations. He knows that mental activities are connected with processes in the central nervous system and that, especially in the brain, localizations of mental activities are found. As a result of the split-brain experiments with patients and animals, some have arrived at the conclusion that there is a double consciousness.An approach from biology can lead to statements of a philosophical character, as, for example, statements about the unity, or even identity, of mind and matter. The theories of identity meet with great interest in scientific circles, and the truth value of identity statements is investigated. The system theory is taken into consideration. On a philosophical level a revaluation of the concept of matter can lead to a different sort of identity theory. (shrink)

Many contemporary bioethicists claim that the possession of certain psychological properties is sufficient for having full moral status. I will call this thepsychological approach to full moral status. In this paper, I argue that there is a significant tension between the psychological approach and a widely held model of Dissociative Identity Disorder (DID, formerly Multiple Personality Disorder). According to this model, the individual personalities or alters that belong to someone with DID possess those properties that proponents of the psychological approach (...) claim suffice for full moral status. If this account of DID is true, then the psychological approach to full moral status seems to entail that the two standard therapies for treating DID might, on occasion, be seriously immoral, for they may well involve the (involuntary) elimination of an entity with full moral status. This result should give proponents of the psychological approach pause, for most people find the claim that current treatments of DID are ethically suspect highly counter-intuitive. (shrink)

In _Consciousness and persons_, Michael Tye. 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. (shrink)