On Personal Identity

I just listened to

Christopher Shields on Personal Identity

Personal identity - the question of what, if anything, makes an individual the same person despite change over time - is an idea that has interested philosophers since antiquity. Christopher Shields discusses this topic in this Philosophy Bites interview.

Here is a fun little story that goes with it (part of the podcast):
 

A borrowed 5 drachma from B.

B says at some point: It's time to give me the 5 drachma!

A: What 5 drachma? Let me ask you a question: If we had a pile of 3 pebbles and took one away, would we have the same pile or a different pile?

B: A different pile

A: And if we added a pebble, would we have the same or a different pile?

B: Well, a different pile

A: Aha, you see, a human being is like a pile of pebbles: There's matter flowing in and out, and each time the quantity changes, we have a new and different person. Therefore it was not I who borrowed the money, but somebody else altogether. So you can't possibly ask me to pay the 5 drachma back!

At this point B smacks A in the face.

A: Why did you do that??

B: Who? Me?