Week 4: Parfit, 'What we believe ourselves to be'

 

DQ1. Here is a reconstruction of Parfitt's argument against using memory as a criterion of identity.

Parfit's Transitivity Argument Against Locke

  1. If the Memory Criterion of Identity is true, then my future Earth-self is identical to me, and also my future Mars-Replica is identical to me (Branch-Line Case).
  2. If my future Earth-self is identical to me, and I am identical to my future Mars-Replica, then my future self is identical to my Mars-Replica (Transitivity).
  3. My future Earth-self is not identical to my future Mars-Replica.
  4. Therefore, the Memory Criterion of Identity is not true.

The argument is motivated by the 'Branch-Line' (Case 2) example of the Teletransporter. Evaluate the validity and soundness of this argument.

 

DQ2. Consider the Physical Criterion and the Psychological Criterion of personal identity:

  1. What does each say about personal identity in the case of the Simple Replicator?
  2. What does each say about personal identity in the case of the Branch-Line Replicator?
  3. What does each say about personal identity insofar as human aging is like the Ship of Theseus?

 

(Optional) DQ3. Parfit says that Psychological Connectedness and Continuity (which he calls 'Relation R') is what matters for moral and political considerations about past and future beings, and that the question of the 'correct' definition of personal does not. Evaluate this claim.