Metaphysics geek dream week

Warning: Major geeking out ahead (metaphysics and sci-fi!!!). Also, MAJOR HEROES SPOILERS from the 4/27/09 episode.

Last night's Heroes totally one-upped last Friday's episode of Dollhouse!

In the April 24 episode of Dollhouse, a murdered Dollhouse client named Margaret Bashford was temporarily resurrected when her mind (which had been copied a few weeks prior to her death) was downloaded into Echo's body. The resurrection was only temporary because at the end of the episode Echo/Margaret's mind was wiped. Then in the April 27 episode of Heroes, Nathan Petrelli, who had just had his throat slit by Sylar, was resurrected when psychic Matt Parkman made Sylar believe that he (Sylar) was Nathan; Sylar's power to know the complete history of any object (or person, I guess) that he touches allowed him to fill in his memory. Heroes went even further than Dollhouse, though, because Sylar's power to shapeshift allowed him to look exactly like Nathan.

We definitely have a theme going on here. Making copies of people's brains to grant them life after death. This is a fascinating plot device because it raises fundamental questions of identity. Is Margaret Bashford still alive? She knows everything that Margaret knew (up until three weeks before her death), thinks like Margaret thinks, and believes she is Margaret, but she is in Echo's body. And who is the man left standing at the end of the Heroes episode? He thinks he is Nathan, and he looks like Nathan, but is he Sylar? The tiny teaser at the end of the episode showed Nathan obsessing over a clock (something very Sylar, if I can turn him into an adjective), hinting that a bit of Sylar remains underneath. But if the transformation had been complete (without any remaining vestiges of Sylar), would he then actually be Nathan Petrelli?

I love thinking about these kinds of dilemmas. Even though I was an engineering major, I managed to fit two philosophy courses in metaphysics into my schedule. And identity was always one of my favorite topics, due in part perhaps to its frequently sci-fi nature. Some people can't stand discussing the issue: "What does it matter? We can't really scan in brains and download them into other people! This is pointless!" But these theoritical scenarios raise questions of how we define ourselves. Am I a certain cluster of molecules? Am I this body, which is allowed small, gradual changes? Or am I this specific set of memories and thoughts and feelings and natural disposition? What makes me me? To the uninitiated, I will attempt an introduction to these sorts of dilemmas (to those who have studied this before, I don't think I present anything new).

One simple explanation of one's identity is one's body. This independent form that looks like me and has all these parts exactly like my parts is me. But this is not a satisfactory explanation by any means. After all, I do not look very much like how I looked when I was three years old. My body may not even have any of the same molecules that it had when I was three. Cells die and I eat food and make new cells. If the completely same body is required for a person to be me, then we are constantly changing identities as we shed cells and make new ones. One could say, "Well, I'm not the same person that I was when I was three," but on the level of identity that I am talking about, that is absurd. If we are constantly changing identities, then I haven't met any of the people in my family, and they haven't met me either. The friends I grew up with are gone. I am a new person, I did not graduate from college, and thus my grad school application was a lie, but I can't be punished for it because I wasn't the one who submitted it. Okay, so the completely same body must not be a requirement for identity. We must allow a gradual change in body in the maintenance of identity. My body is not completely different moment to moment, so as long as it proceeds to change bit by bit, I will still be me.

Another definition of identity is my brain. Not my physical brain, since that is a part of my body, but my memories, tendencies, way of thinking, etc., which I will refer to collectively as my "psychology". This also changes constantly but, like with the body, it is a gradual change; the same defense of this definition of identity may be used.

So which am I, the body or the psychology? Are both required, or just one? Which one is more important? Consider death. P1 is alive at t1, but dies at t2. The psychology is gone, but the body remains (at first... though unless cremated it will continue to change gradually). The neighbor hears the gunshot and comes in to find a body, P2, dead on the floor. Is P2 the same entity as P1 (does P1=P2)? To those who say no, consider a case of sudden brain death. The body P2 is still alive, but the psychology is totally gone. In this case, does P2=P1? If P2 is not P1, then who is he?

Now, what if P1 knew that he was going to go brain dead at t2, so at t2 he arranged to have his entire psychology scanned into another body, P3. The plan works, so now we're left with P2, a brain-dead empty shell, and P3, who in spite of a new body feels quite like his old P1 self. Which of these is P1? The body P2, which is molecularly the same as P1, or P3, whose psychology is the same? They can't both be P1; if P2=P1, and P3=P1, then P3=P2, which is definitely not true (the brain-dead person has neither body nor psychology in common with P3; they are not the same person). So which is it? Consider the reactions of the family members. Assuming they get over the shock of having their loved one talking out of the body of P3, they would probably embrace P3, who knows them and loves them, and leave the brain-dead P2. This is similar to the Margaret Bashford case, except that in her case P2 is actually dead, not just brain dead, and P3's psychology is a continuation not of P1, but of a P0 who had her brain scanned three weeks before her death at t2. Does this make a difference in the question of identity? Does the body of P3 matter? If P3's body once belonged to a different person, does that make us less likely to accept that P3=P1 than if the body were a synthetic Cylon skin job type of construct (which looks like a human). If the body of P3 looked exactly the same as the body of P1, would that help confirm that P1=P3? This is similar to the Sylar/Nathan case.

Are you still with me, or have you ready to haul me to the loony bin? I'm going to switch gears slightly to one of my favorite examples: the Star Trek transporter. Now, I am not entirely certain of how transporters are supposed to work in Star Trek; I am totally psyched about the upcoming movie, but I am not a Trekker. However, this is a thought experiment, so whether or not this explanation is true to the Star Trek world doesn't matter.

Captain Kirk steps onto the transporter and says, "Beam me down, Scotty." Scotty presses the button, and the transporter scans in all the information that is Captain Kirk, vaporizes his body on the ship, then reassembles Kirk on the planet using the molecules on the planet into exactly the same configuration that Kirk was in on the ship. Kirk down on the planet brushes himself off and commences to explore the planet. Is the Kirk on the planet the same person as Kirk on the spaceship? The people in the Star Trek universe certainly believe so. The other option is that Kirk died in the vaporization, and this man on the planet is an imposter who has no right to the title of "captain". In the world of Star Trek, transportation is not murder, but a convenient way to get from here to there. They believe that K2, Kirk on the planet = K1, Kirk on the ship.

Now, let's say that the transporter is not working properly. K1 steps onto the transporter and says "Beam me down, Scotty," and the transporter scans him in and reassembles K2 down on the planet as in the previous case. The only problem is, the vaporization didn't work, so now we have K3 still standing in the transporter saying, "Scotty, what went wrong? Why am I not on the planet?" while K2 is happily exploring the planet without knowing that anything went wrong. It is clear that K2 does not equal K3, since one is on the planet and the other on the ship, but then which one is the same person as K1? In the previous example, we, and the denizens of the Star Trek universe, had decided that K2 was the same person as K1, but now it is hard to imagine that K3 is not K1. K3, after all, has the advantage of being continuous in both psychology and body to K1. But K2 has the advantage of intention: K2 is the one who is supposed to exist; K3 is a mistake. Imagine the epic showdown between Kirk2 and Kirk3: It's a fight to the death, winner takes all!!!

It is probably clear by now that I could go on and on about this topic. I hope you don't think I'm entirely insane. Hopefully you appreciate the relevance of this issue (no, it's not as immediately important as what you're going to eat for lunch today, but it still is a sort of fundamental question about our lives). And maybe you find it interesting and will now spend some time thinking through these questions and coming up with scenarios of your own. If that is the case, then welcome to my world.

There's a new episode of Fringe tonight. As a show about the fringe sciences, this scenario is right up their alley. I've got my fingers crossed...