On Yale's open course phil-176, lecture 6

UPDATE: I had to go in and fix some stuff; Blogger's WYSIWYG editor is TERRIBLE. Sorry about the funky formatting.

(I've been listening to the lectures from this series on the philosophy of death. They are rather interesting and seem to be very well-thought out. Below are some thoughts I had on a particular section of Lecture 6, shown above)

Shelly Kagan, a philosophy professor at Yale, explains, starting at around the 5:52 in the above video, a interesting and quite illuminating counter to Descartes' argument for the existence of the soul. The Cartesian argument goes something like this:

1. I can imagine my soul (essentially synonymous with mind/subjective experience/stream of consciousness, in this case) existing without my body. (Try it. It shouldn't be too difficult).
2. I can imagine my body existing without my soul. (Give it a try).
3. If I can imagine thing A existing without thing B existing thing A and thing B must be separate and distinct things. Furthermore, if I cannot imagine thing A and thing B existing separate from each other, they must be identical and non-distinct from each other (they must be the same object).

Here it would be helpful to provide an illustrative example: I can imagine my arm existing without my hand, and vice versa, or my left hand existing without my right hand. My arm (excluding the hand) and my hand are two distinct things, as are my two hands. On the other hand (pun intended), I cannot imagine my left hand existing without my left hand existing (can you?). And my left hand is identical and non-distinct from itself.

Now, to tie it all together:

1. I can imagine my soul (essentially synonymous with mind/subjective experience/stream of consciousness, in this case) existing without my body. (Try it. It shouldn't be too difficult).
2. I can imagine my body existing without my soul. (Give it a try).
3. If I can imagine thing A existing without thing B existing thing A and thing B must be separate and distinct things. Furthermore, if I cannot imagine thing A and thing B existing separate from each other, they must be identical and non-distinct from each other (they must be the same object).
4. Because I can imagine my soul existing without my body (or vice versa--whichever happens to be easier for you to imagine), my body and my soul must be two distinct and separate things.

Okay. Now that that's out of the way, we can look at the counterargument. Watch the video from around 5:52 to 19:25. If you're lazy, and want a tl;dr, read the next paragraph. Otherwise, you can skip to the one following.

You may have heard of the two stars called the morning star and the evening star. The evening star appears just after sunset; the morning star just before sunrise. The argument is as follows:

1. It is possible to imagine a world in which the morning star exists and the evening star doesn't
2. [Premise (3) from the earlier argument.]
3. The morning star and the evening star must be two distinct objects.

Now, that argument might look fine--but it just so happens that the evening star and the morning star are the same celestial body! They are--or it is--the planet Venus (not even a star in the first place) appearing at different times of day. (Note that this does not necessarily prove that the soul and the body aren't distinct--just that the Cartesian argument is not sufficient to prove that they are, because premise (3) is false).

You're back from watching the video? Good, now that everyone's on more or less the same page...

Kagan stated in the beginning of the lecture series that he did not believe in a distinct soul, and I think (he might have just implied it--I don't remember) that he also mentioned that he thought the "soul" or "mind" is a manifestation of the body. It is, in other words, something the body does, just as (to use his analogy) a smile is something that a part of your body (your mouth) does, but it is not a separate thing. Furthermore, you can't have a smile without a mouth (this goes back to the existence argument--you can have a mouth without a smile, but you cannot have a smile without a mouth--what does this say about premise (3) from before? I don't know yet...). One can say that a smile is an emergent phenomenon which depends on the mouth for its existence. It is not a part of the mouth. It is something that a mouth does. Similarly, our experience of the evening star (or of the morning star) is a manifestation or emergent property of Venus. The evening star is not a part or component of Venus; it is a particular way that Venus appears to us. Appearing just after sunset (or just before sunrise) to viewers on the planet Earth, is something that Venus does.

So, a major question is, how does this argument match up with the Cartesian argument? There are a few major possibilities:

• The mind is analogous to the evening and morning stars; Venus is analogous to the body (I would guess that this is the analogy Kagan prefers, based on what he has said so far). This would imply that the body is the basic* phenomenon, and that the mind is the emergent phenomenon.
• The mind is analogous to the evening star; the body is analogous to the morning star (or vice versa). This would imply that the mind and the body are both emergent phenomenon of some more basic phenomenon.
• The body is analogous to the evening and morning stars; Venus is analogous to the mind.
• We live in an alternate universe in which the morning star and the evening star are actually two separate celestial bodies (the mind and the body happen to be separate).

*i.e., non-emergent. I use the term in a relative sense, as it is probably possible to have emergent phenomena of emergent phenomena. Higher level programming languages seem to be, with my limited knowledge of computer science, emergent from lower-level languages, which are in turn emergent from the little electrical charges on the computer chip (any of you computer science people know more about this? Leave a comment). If you believe minds are emergent, a society or group is a phenomenon which emerges from several emergent phenomena--human psyches.

I think it is very possible that the first three interpretations are actually indistinguishable if one takes a view of extreme skepticism, which is, ironically, just like the one Descartes held (the fourth interpretation probably deserves its own post, so I'll save it for later). If you're familiar with "Cogito ergo sum" or The Matrix, you know that it is, in principle, possible that the world as we know it does not really "exist"; that there is some deeper reality behind everything we see. The only thing we know is that our consciousness must exist in some sense--otherwise, we could not begin to ask ourselves whether we existed or not!

Similarly, if the mind and the body are not necessarily separate entities, but could in fact be emergent phenomena of each other or of an unknown entity, how would we know? How would be able to tell the difference? Is it not possible that we are metaphysical brains-in-vats; that our sensory experiences of our bodies and the world around us emerge unassisted from our minds (whatever they may be)? What if our minds themselves, in this scenario, emerge from something else altogether? Is it not possible that our minds are simply an illusion created by our bodies? (And that our bodies in turn are created by something else)? Is it not possible, in fact, that both our minds and our bodies are illusory emergent properties of some larger, unknown or unrecognized system? We can't know.

As a final point to round out the above line of inquiry, I think that these possibilities are not only empirically indistinguishable but also can be separated only by semantics. Does the mind emerge from the body? Does the body emerge from the mind? Do they both emerge from something else? You say tomayto, I say tomahto. On the one hand, research like that explained in The Self Illusion

would seem to indicate that our conscious experience, personality, or egos are illusory feelings and thoughts created by the brain. (What does that mean? Are any thoughts illusory? Aren't all thoughts?) On the other hand, we cannot truly be certain that our physical world is not the dream of a giant celestial bug monster, or some future humans' elaborate immersive simulation, or something like that. So the body might be an emergent property of the mind (which is in turn an emergent property of the body, etc.) And whose to say our bodies and our minds are not simply virtual objects in a vast computer network (although we don't have to be virtual to be one of those)? 

Is it really meaningful to ask any of these questions? I think it suffices to realize that, in the world as we are able to experience it, the current empirical science seems to indicate that, at the very least, there is some level of reality on which the mind emerges from the brain. To borrow an analogy from Stephen Hawking (from the beginning of The Grand Design, I believe), our world might as well be a fish tank. We may create very complex laws of physics to explain why objects appear to move in such wonky ways through the curved glass surface of our watery home. And since we can never know the world that lies outside (this is a perfect metaphysical fish tank, not a real one), the best thing for us to do is use our fishy theories to figure out when and how objects outside the tank might move. It makes no difference to us whether there is another world outside the fish bowl or not. It also makes no difference whether the "outside world" is in fact another fish bowl, or whether the entire world is "fishbowls all the way down." By the same token, we might never know the "true" nature of reality--whether there is a deeper reality beyond our own, of which our reality is but a part, or an emergence, or a chain of parts or emergences--but for our purposes it suffices to know the laws of our own world and our own minds.

There is only one realm in which it could possibly matter--and that is in all of our inevitable exits from this world (is Goldy who disappeared last week really gone, or did the owners just flush him down the toilet?). I am going to assume, considering the title of the lecture series, that Kagan is going to touch on this at some point. His thoughts so far bring to mind some Eastern views on reincarnation, which I can't say I believe, but are certainly worth a look as a challenge to the currently fashionable view that materialism must imply the ceasing of conscious experience upon death. 

So tune in next week (ish) for an update!