Personal Identity Dr. Ron Mallon

Why Care About Personal Identity? Survival (Death, Dying, Afterlife, etc.) Individual Change Responsibility

How shall we proceed? Consider various cases in which we compare two entities over time Make judgments about those cases Try to develop a theory that systematizes those judgments Example of an a priori approach to a philosophical problem

Possible Criteria Psychological Continuity (Mind) Bodily Continuity Social Continuity

Often times we can describe the same case in two ways E.g. John Perry’s “The Problem of Personal Identity” Case Psychological Description: “The morning of the committee vote you wake up … Something seems strange. … Puzzled, you go to the mirror. Staring out you see not your familiar clean shaven face and squatty body, but the strapping frame and bearded countenance of [your enemy] Peter Pressher”

The ‘Body Transplant Peter’s Brain goes to Your Body Your Brain goes to Peter’s Body

The Psychological Interpretation You are in Peter’s body, Peter is in your body. You are where your personality and memories go.

Example 1: Mind & Body Suppose that in the future, scientists develop the ability to perform ‘open brain surgery’. In this procedure, surgeons remove a person’s brain from that person’s head in order to perform surgical procedures more effectively. The brain is then replaced, and the head closed. Suppose that one day two patients, Brown and Robinson, were having open brain surgery at the same hospital. Unfortunately, during the procedures, the surgeons became confused and Brown’s brain was placed in Robinson’s head, while Robinson’s brain was placed in Brown’s head. Due to complications, Brown’s body (containing Robinson’s brain) died immediately. But Robinson’s body (with Brown’s brain) lived on, and eventually woke up from the surgery. The patient was in Robinson’s body, but seemed to have the beliefs, desires, character, and memories of Brown. For insurance purposes, the doctors must indicate which person has survived the operation. Who should they say has survived? Brown has survivedRobinson has survived

Example 2: Mind & Body Imagine that in the distant future, a skillful surgeon switches the brain of Eva with the brain of Sammy. At the completion of the operation, Eva’s body wakes up and talks as if she has no memories of the things Eva’s body has experienced. But she does seem to have memories of what Sammy’s body has experienced. And Sammy’s body talks as if he has memories of what Eva’s body has experienced, but no memories of the things Sammy’s body has experienced. Soon after they undergo the operation, it comes to light that several months before the procedure, Sammy committed a horrible murder. As a result, the police decide to arrest Sammy. Which one should the police arrest? Sammy’s body with Eva’s brain and memories Eva’s body with Sammy’s brain and memories

This Class

But wait … The Physical Interpretation “You are a Senator … One morning, you wake up seeming to remember being Peter Pressher … A man emerges from a bedroom who seems to remember being you. … What actually happened … is that two people underwent radical changes in character and personality, and acquired delusive memories, as a result of brain surgery.” (Perry, 5-6)

It’s Possible To Manipulate the Cases to Cue into the Body Lack of a ‘closer’ candidate Cued into identification with the body Something at stake?

Example 1: Body over Mind Simon hated dogs so much, that he used to roam the neighborhood and poison dogs. One day, when he was on his way to the store to buy more poison, Simon got into a bad auto accident and suffered a head injury. The accident caused Simon to lose his memories: he could not remember his family or his childhood, and he no longer hated dogs. In fact, he couldn’t remember anything from before the accident. He didn’t even remember disliking dogs! Luckily, his family visited him often in the hospital, and eventually they brought him home and cared for him during his recovery. Shortly after he returned home from the hospital, the police came to Simon’s home. Apparently, someone had videotaped Simon poisoning dogs, and the police had come to arrest Simon for cruelty to animals. But when they arrived, Simon explained that he has no memory of poisoning dogs. The doctors confirm that Simon has no memory of the poisoning. Should Simon be punished for dog poisoning anyway? YesNo

Example 2: Body over Mind Mr. Chan has a degenerative spinal cord condition that requires extremely painful surgery to correct. Unfortunately, there is no way for doctors to numb the pain during this operation. Mr. Chan does not want to undergo the operation if he has to undergo the pain. The doctors develop a way around this problem. They give Mr. Chan a drug before the operation that causes him to lose all of his memories. After the operation, the doctors give him another drug that both restores his old memories and also causes him to forget the intense pain of the operation. The physician explains that, “With these drugs, while it is true that my patient was in very intense pain during the operation, the patient was not Mr. Chan” Is the doctor correct? Did Mr. Chan avoid the pain? YesNo

Favoring the Body?

What do these examples show? One thing they might show: Psychological continuity is sufficient, but not necessary.

The Robot Case Suppose that, in the future, brain scans become so accurate that scientists can read a person’s beliefs, desires, intentions, and character from a brain scan. And suppose that scientists can then transfer these mental features into a neural net which can then be placed into the body of another person or a robot. When Melanie dies, the scientists decide to go a step further. A few days after her death, scientists take a scan of her brain and are able to recover a reading of her mental states. They then transfer these readings into a neural net that they place into a humanoid robot body. The robot awakens, and it claims to be Melanie. Moreover, the robot seems to act like Melanie and have Melanie’s memories. Despite all this, Melanie’s family does not accept the robot. They refuse to talk with it, or to allow it into their home. The robot cannot even acquire Melanie’s things from the family home. This makes the robot very sad. Is the robot Melanie? YesNo

Melanie