Personal Identity Through Time

Personal Identity Through Time

1. Types of change

   • Qualitative change
     • changes to an objects properties: painting a chair
   • Numerical Change
     • when something changes so radically that it is no longer the same object, example: reducing a chair to a pile of ashes
     • important for issues of personal responsibility - the general and the boy picking apples in the orchard Reid

2. Where does our unity of identity come from?

   • DESCARTES concluded that the essense of the self, because of inevitable constant physical change must be completely non physical in order to have unity of identity. The mind is NOT composite but the body IS. Cartesian Dualism
     • the cogito
   • LOCKE argued that the mind is not what underpins personal identity, as if we were reincarnated we would not be able to concieve of ourselves as the person in our previous life. Emphasis is on identity
   • HUME argued that we discover our identity through memory, and that at the core of our identity we are a 'bundle' of perceptions. Descartes countered this by asking who owned this bundle.
   • WILLIAMS rejects the view that only psychological continuity is important, saying that we recognise eachother physically, and that having a physically consistent brain is enough
   • KANT argued that as we could never hope to know anything about the self other than that it exists - so we must conclude that the concept of self or 'I' is logically primitive, as STRAWSON argued.
   • PARFIT is Lockean inso far as he believes that psychological connctedness is important, but they differ in his emphasis on survival rather than identity. Transitivity of memory.

3. physical

   • although we are constantly growing/changing, we exist continuously, so we can be said to have physical continuity to a degree
     • Theseus' ship
       • using this Hobbes suggests that despite complete numerical change, the ship is the same entity as the change happened over a long period of time
   • is it necessary?
     • Teleportation thought experiement
       • using this parfit suggests that physical continuity is not necessary, as if we are destroyed and replicated our identity remains intact.
   • is it sufficient?
     • Brain transplant thought experiement
       • Shoemaker's example suggests that physical continuity is not sufficient, as the mind survives in the absence of the original persons body.

4. psychological

   • based on the unity and connectedness of our minds through time
     • Prince and the Cobbler
       • Through this example Locke suggests that there is a difference betweet person and man
   • Is it necessarry?
     • The General and the Boy
       • Reids example demonstrates that forgetfullness could cause problems of responsilibilty in personhood through time, as some of our 'selves' are linked and others are not, however continuity remains through links between each self.
   • Is it sufficient?
     • Brain brothers
       • Parfits experiemnts suggests that phsychological continuity is not a sufficient condition for personal identity because even though the criteria for continuity have been met, we would not condier both of his brohers to be Derek

5. Survival Vs Identity

   • SURVIVAL is a broader term, and allows for continuity through transitivity rather than sameness
     • However, it is perhaps too elusive, and thus not practical for implementation in court cases etc.
     • Parfit's Prague example
   • IDENTITY implies sameness, or the need for at least one distinct unchanging characteristic