


Maybe what makes you you is your brain’s data-your memories and your personality. This suggests a new theory we’ll call the data theory, which says that you’re not your physical body at all. Under Locke’s definition of you, the new Bill Clinton in this latest example is you, despite not containing any part of your physical body, not even your brain. Philosopher John Locke’s memory theory of personal identity suggests that what makes you you is your memory of your experiences. The body and brain of Bill Clinton would still run out and go freak out about this to your family. And again, after a significant amount of convincing, they would indeed accept that you were alive, just in Bill Clinton’s body. After all, Bill Clinton’s brain now has all of your thoughts, memories, fears, hopes, dreams, emotions, and personality. What if the mad scientist, after capturing you and Bill Clinton, instead of swapping your physical brains, just hooks up a computer to each of your brains, copies every single bit of data in each one, then wipes both of your brains completely clean, and then copies each of your brain data onto the other person’s physical brain? So you both wake up, both with your own physical brains in your head, but you’re not in your body-you’re in Bill Clinton’s body. Meanwhile, your old body would not be you-it would be Bill Clinton. So what makes you you must be your brain. The brain theory says that wherever the brain goes, you go-even if it goes into someone else’s skull. You’d still feel like you, just with a different body. So unlike your other organs, which could be transplanted without changing your identity, when you swapped brains, it wasn’t a brain transplant- it was a body transplant.
