The Social Brain (Gazzaniga1987)
Gazzaniga does newresearch on the split-brain patients of his(teacher and ? ) colleagueRoger Sperry
Nobel 1981(1913 – 1994)
Split Brain Argument (373)
Premise 1. Surgical separation of brain lobes yields 2 streams of consciousness.
Premise 2. There are three possibilities:
2, 1, or 0 persons.
Parfit to argues for 0 person theory.
Person Theory
Two Person Theories
[Parfit does not consider all theories]:
Ego (Cartesian)
Bundle (Hume) = no self
Parfit argues for Bundle theory:
a no self/ego/person theory.
Buddha
[Parfit’s argumentam ad verecundiam?]Buddha says
Self is “only a conventional name given to a set of elements.”
Analogue: carriage. [Cf. computer, plant, animal]
Parfit: “Most of us therefore…have false beliefs about ourselves.” (375)
Teletransportation Arguments
Point: to reveal our false beliefs. (375-7)
Case: original brain and body destroyed, and perfect replica made.
Range: different proportions of cells in brain and body replaced.
Variant: original is not destroyed, and replica still made.
Teletransportation Arguments
ARGUMENT (375-6): [cf: Lycan’s “Henrietta”]i) Variant case shows result of 100% replacement
is not you.ii) If only 1% of cells replaced, then the result is you.iii) Assume result either is you or is not.
[identity is all-or-none]iv) It is “implausible” that a precise percentage
maintains identity.SO: There is no such thing as
personal identity.
Club Analogy Argument (376)
Personal identity is like
[is analogous to] club identity.
But: there are no criteria for
club identity.
SO: there are no criteria for
personal identity
Parfit’s take on teletransportation
“You do not merely want there to be psychological continuity between you and some future person. You want to be this future person. On the bundle theory there is no such special further fact…judged from the standpoint of your natural beliefs, even ordinary survival is about as bad as teletransportation.”