Many of you are probably familiar with the story of Phineas Gage. He was widely regarded as a kind and generous man, but he suffered from a freak accident during his work on a railroad, and the result was that a railroad spike ended up entering his brain. After the accident was over, the person who remained was not a kind or generous man. He was impulsive, callous, and clearly lacked all of the moral virtues that Phineas had previously shown.
Now, let's consider this case as a problem of personal identity. In particular, let's ask yourself whether the following sentence is correct:
- The original man named Phineas does not exist anymore; the man after the accident is a different person.
Many people have the intuition that this sentence is correct. It might seem, then, that our intuitions conform to an approach to personal identity that emphasizes psychological similarity. Since the man after the accident is not sufficiently similar to the original Phineas, we conclude that they are not the same person.
In a new paper in Analysis, Kevin Tobia make an incisive criticism of this interpretation. As he points out, it is indeed the case that the man after the accident is dissimilar in certain respects from the original Phineas, but there is also another quite salient fact about him. Specifically, he is morally worse than the original Phineas. That is, it is not just that he differs psychologically in some way; he specifically differs by lacking some of the original Phineas's moral virtues. Might that be the explanation of our intuitions here?