Huemer's Argument For Reincarnation Implies That You Can Be In Multiple Places At Once

But you probably can't be in multiple places at once

There are two types of philosophical undead that philosopher extraordinaire Michael Huemer believes in. The first kind is relatively straightforward: the philosophical zombie. These zombies, being the brainchildren of philosophers rather than Hollywood screenwriters, do no more shambling or brain-eating than the average human (thank god for that!). These brainchildren avoid children’s brains. Instead, philosophical zombies are beings that are physically identical to humans—exactly the same molecule for molecule—but that lack consciousness. Thus, the zombie version of me would sit at my computer, typing out brilliant pose, looking just sublime, in exactly the same way as I do, but would lack consciousness. As Chalmers says, all is dark inside the zombie. The zombie version of me does not think as I do, or at all, though it does act exactly as I do. There’s more to say about such beings, but seeing as my invocation of them is merely a convenient plot device to describe Huemer’s view on reincarnation, I shall speak of them no more.

The second kind of undead that Huemer believes in is reincarnated beings. Huemer thinks that long after my heart stops, long after my brain has long since dissolved into soil and been devoured by bugs, bacteria, and snakes, I will rise again, in a different time and place. You see, Huemer thinks that I am just a soul, and the soul will latch onto a different body.

What the heck is a soul? It’s a non-physical thing that is supposed to ground personal identity. Souls seem weird to a lot of people, but they do explain our intuitions about personal identity. For example, the reason that I would remain the same person even if my body was replaced by metal is that, though my body would be different, my soul would be the same. If someone on the other side of the universe had the same conscious experiences as me, his mental states might be the same as mine, but he might nonetheless not be me. Why? Because I am my soul and while I’m sure he has a very good soul too, it would not be mine. Experiences don’t just exist in the void—they are experienced by someone. The thing that makes your experiences experienced by you is that they are had by your soul.

I’m a bit dubious about this whole soul business. But there are some pretty convincing arguments for it, so I’m pretty uncertain. Maybe there are souls, maybe I am just a soul, but I’m not convinced. If you enjoy watching one of the rare occurrences in which the author of this blog is destroyed in a debate on whether or not souls exist, see here.

But let’s grant that souls exist. Huemer certainly thinks that they do. If they do, it’s not inconceivable that my soul could rise again—that it could eventually be attached to a different body. If this happens, I will rise again, with none of my previous memories.

Okay, so maybe this shows that it’s possible that reincarnation could happen—that after I die my soul could latch onto the body of someone else, resulting in me once again existing. But why in the world would we think that this actually will happen? Arguments of the form “it’s not utterly inconceivable that X could happen, therefore X does happen,” are, of course, fallacious. Fortunately, Huemer has a fascinating argument for the conclusion that reincarnation happens. It involves appealing to a few premises.

1. I exist now (controversial!).

2. If the past or future is infinite, and there is no reincarnation, the odds I’d exist now would be zero.

3. The past or future is infinite.

4. So there is reincarnation.

1 is obviously true. 3 is not argued for but seems to be widely believed, so let’s just grant it as a premise. Huemer has a bunch of arguments for the conclusion.

But why think 2. Well, if there’s no reincarnation, then you’ll only live once. But if you only live once, what are the odds you’d be alive this particular year? Well, you’d be alive one out of the infinity years, meaning that the odds you’ll be alive during this year in particular are 1 divided by infinity. 1 divided by infinity = 0. So the odds that you’d be alive during this particular year are 0 if you only live once. In contrast, if reincarnation is possible, then after you die, you’ll rise again, thus living in lots of years. As a result, if there is reincarnation, it’s not terribly improbable that you’d be alive during this year in particular. Thus, if there’s no reincarnation, you wouldn’t be around now, but you are around now, so there is reincarnation—capiche?

Now, maybe this argument rests on some weird anthropic reasoning. Anthropic reasoning involves reasoning about what the odds are that you’d be in some particular circumstance. If you want to read more about it, Google the doomsday argument or just anthropic reasoning generally. What people who think hard about anthropics tell me is that it gets very confusing, and having thought about it a bit myself, I’ve been nothing but confused, so I won’t weigh in on whether Huemer’s basic argument is right.

I’m sort of suspicious that Huemer’s argument is like waltzing into a room and declaring that we should think that there are no other rooms, because if there are no other rooms then there’s a 100% chance that you’d be in that particular room, or is illicit in some way, but I’m not so sure. What’s more interesting, though, is that you can use Huemer’s argument to argue that your soul can latch onto multiple bodies at once—that you can be in multiple places at the same time. The argument for this is as follows:

1. I exist here.

2. If space is infinite, and I can’t be in multiple places at once, the odds I’d exist here would be zero.

3. Space is infinite.

4. So I can be in multiple places at once.

Now, I don’t think space is infinite any more than I think that the past or future is infinite, but most people disagree with me, so I’ll just assume that 3 is true. The point of this is mostly to illustrate what would be true if space were infinite, not to settle the question of whether it is, in fact, infinite. And Huemer thinks that space is infinite, so I think this should be convincing to him.

Why think that 2 is true? Well, if I can only be in one place, then I’ll be in one random place in an infinitely large universe. But the odds that I’d be in this particular part of the infinitely large universe are one divided by infinity, which is zero. So if I can only be in one place at once, the odds that I’d be here are zero; thus, the fact that I am here is infinitely strong evidence that I can’t be in only one place at once.

What should we take away from this argument? I think one of four things.

1) Maybe we should think that the self doesn't really exist in a robust sense, so the data that you have is just that there is a chain of psychological continuity comprising your consciousness.  On this view, the odds that your chain of psychological continuity would be here now are decently high.

2) Perhaps we should think that there is some anthropic way to avoid the argument.  I
haven't thought too much about this option, so I’ll leave it to the well-dressed people in suits who say things like “well, that assumes a controversial self-sampling assumption that’s been criticized by Glitchfield et al 2001.”

3) We could avoid the puzzle by thinking that the universe is finite in size.

4) Finally, we can just bite the bullet and accept that your soul can be in multiple bodies simultaneously. 

I’m personally pretty attracted to all of these options. But I think lots of people wouldn’t want to accept any of them, so I’d be curious about what they’d say.