Immaterialism and replacement

For the previous two Mondays, owing to the inspiration of Kagan's online Philosophy of Death lectures, I've written about a couple of problems with the physicalist notion of personal identity: resurrection and duplication. To summarize: resurrection is the reconstruction and revival of the body of a deceased person; duplication is the creation of a body identical to that of a living person. Both cases are similar in that they involve two identical copies of one body whereby the copies are made disjoint by a break in continuity. In the case of resurrection that break is in time by way of death; in the case of duplication that break is in space by way of replication. The problem each presents for physicalism is that, according to the physicalist notion that personal identity is purely corporeal, discontinuity shouldn't matter to personal identity. But according to common intuition about identity in general, as shown when we think about bikes and block towers being reassembled, discontinuity seems to matter.

I wrote about resurrection and duplication to lay the foundation for expressing my own view about personal identity—which, as I've already alluded to, is that common intuition is misguided. But before I move on to explaining myself, I want to address an objection many people would raise now, if not sooner: that physicalism is wrong from the start because it neglects the non-physical aspect of a person's existence—i.e., their soul.

Far be it for me to convince anyone who believes in immaterialism to change that belief. There's no bulletproof argument against the existence of souls for the same reasons there are no bulletproof arguments against the existence of anything that's unfalsifiable. I've written about that here. I'm not going to argue against the existence of souls—not in this post.

Instead, I'll point out that immaterialism leads to the same kinds of philosophical conundrums as physicalism does. In particular, theories about immaterial existence struggle with discontinuity, too. First of all, immaterialism also suffers from the problem of duplication: Supposing a soul is copied into a second body, do the two souls constitute the same person or two different persons? Just as with duplication as it pertains to physicalism (and the case of two William Rikers), the answer isn't clear.

Replacement

A problem that's unique to immaterialism is replacement. Replacement is the swapping out of one soul with another. For example, if Jones goes to sleep one night with a soul, X, but wakes up with a different soul, Y, then his soul has been replaced.

Replacement may sound implausible, but the problem isn't how likely replacement is to occur. Instead the problem is: how can you know if or when replacement occurs? In short, the answer is: you can't.

Because souls are immaterial, they are undetectable by direct observation. Instead, we observe souls only by indirect means, such as knowing a person's behavior, memories, and desires. If a soul is swapped out with a soul that produces the same behaviors, memories, desires, etc. as the first soul, then it's impossible to know replacement has occurred. To everyone outside that person, it will appear as though one soul has existed all along, undisturbed. Even to the person (or persons) of the replaced soul, the newly swapped-in soul could produce all the same qualia as the previous soul did, thus giving even Jones the himself the illusion that no replacement occurred.

I won't elaborate on the problem of replacement. Just as I'm not going to argue against the existence of souls, it's not my purpose to argue the merits of replacement as an objection to immaterialism. Instead, my point is that while many people may think immaterialism is immune to the kinds of problems of continuity that plague physicalism, both belief systems suffer their share of problems. It's that both systems suffer these problems that leads me to my view on personal identity, which I'll explain next Monday.

F' parentheses

Most parentheses annoy me. Too often they interrupt the grammatical flow of a sentence. Too often they hide digressions that would be better left unsaid. Too often they're used as stream-of-consciousness crutches, as though they give the author a pass from having to clarify thoughts before putting them into words. And too often parentheses are just plain ugly.

But my biggest problem with the parenthetical is something else. Too often—and once is more than enough—parentheses are used for evasion. They're accomplices to an author whose crimes are obfuscation and bullying the reader. The parenthetical is passed off as a casual aside but is instead the author's main point or tenuous assumption—as though punctuation can shield a bad argument. Maybe this kind of disingenuousness fools some readers, but it makes me want to disagree with everything the author says, if only on principle.

Take the following, an example of parenthetical slyness:

Since we cannot get inside the mind of another creature—or another human being for that matter—we can never be sure whether that creature is self-aware. (Observations of the way chimpanzees behave in front of mirrors do not demonstrate self-awareness, despite claims to the contrary.)

It may very well be that chimpanzees' behavior in front of mirrors doesn't demonstrate self-awareness, but that's not obvious to me. Has that assertion been backed up elsewhere? I don't know, and the author doesn't alert me to the evidence. Rather, I'm supposed to take it on faith.

Reread the passage and imagine it without the parentheses. The last sentence hangs in the air, speculative and meaningless. I wrote sentences like that for college papers when I procrastinated too much or was otherwise too lazy to find sources or explain myself. If colleges had teeth they would flunk students like me—or at least make me go rewrite the paper. But somehow when bald speculation is cloaked in parentheses it's good enough for publication; and we're supposed to accept it as fact. (This is nonsense.)

Here's an example of parenthetical browbeating, taken from a comment here at JEC about metaphysics:

We know that cataracts are privations because we know the purpose of the eye. The eye enables us to see, therefore its function is to enable human beings to see (note how this is a basic, evident truth, without need of argumentation. We're able to discern the function of things the same way we are able to know that there is an external world, or that change exists; i.e. Through direct, more-or-less immediate observation).

When I encounter a parenthetical like this, it occurs to me that all the words outside the parentheses are throwaway; it's the stuff inside the parentheses that marks what the author is really trying to say. And what the author says here is: I forbid you to disagree with me. But it's unacceptable to openly browbeat, so instead that message is shoved into a pair of parentheses, where it masquerades as a casual, offhand observation. The result is awkward, like those group conversations where someone disagrees with you but doesn't outright say so. Instead, that person lowers their voice and expresses their disagreement to the person sitting next to them, sure that everyone can hear them anyway. It's not bullying if you don't say it to someone's face, right?

Here's an example of parenthetical diversion, taken from an essay about starting an open source software project:

I started making designs ... and sent them around. Nothing happened. I tried to get people involved, but collaboratively working on a design is very hard (besides, it is probably not the best way to create software in the first place).

This is a case where parentheses are used in lieu of the author taking the more responsible action of using the backspace key. The author makes a valid point based on firsthand experience—that collaborative design is hard—but can't resist tossing in another, unsubstantiated claim: that collaborative design is bad. This extra claim doesn't add anything to the author's point, but otherwise this example is like parenthetical slyness in that the reader is expected to accept a claim without reason.

Parentheses have their place, and they are useful from time to time for clarification. But parentheses should be exceptional, and they should never express new ideas.

Physicalism and duplication

This is another post I'm inspired to write in response to Shelly Kagan's Philosophy of Death class, which is freely available online.

Last week I wrote about physicalists' problem of explaining resurrection: is a resurrected person the same person after death as before death? Or is a resurrected person a new person? Borrowing from Kagan, I gave two analogies to the problem that each suggest a different answer. The first analogy involves a bicycle that's taken apart, fixed up, and put back together. In that case, there seems to be only one bicycle throughout, both before and after the fix-up. But in the second analogy, which involves a boy's block tower that's destroyed and rebuilt by his dad, there seem to be two distinct block towers, one before the destruction and one after the reconstruction. I said I think the first analogy has it more right, that in the second analogy both towers are the same tower, but also I think both analogies miss the point.

But before I divulge how I think the analogies miss the point, I'm going to describe another problem for the physicalist view: the problem of duplication. Duplication is like resurrection but without the person first dying. Instead, two identical copies of the person's body exist simultaneously. In the block-tower example, duplication happens if the block tower isn't knocked over, but instead the dad builds an identical tower to the first while the first tower still stands. Are both towers the same tower? Or are they different towers?

But why resort to using examples of block towers? Science fiction gives us the same scenario with real people—albeit of the fictional variety. In the Star Trek TNG episode Second Chances, Commander William Riker leads an away team to the surface of the planet Nervala IV. The mission is a routine one other than how the planet has a strong distortion field that makes transporting impossible for eight years at a time, while the planet is too far from its sun. The away team has a three chances over four days to get in and out.

However, after first beaming down to the planet's surface, the team is surprised to discover the presence of another human, one who appears to be just like Commander Riker. The man says he is Riker and that he's been stranded on the planet for eight years ever since he failed to transport out in time during his last mission. The away-team Riker corrects him, saying he (the away-team Riker) was there eight years ago, but he transported out OK. But neither man's account explains how there are now two Rikers, and the away team, along with the new Riker, beam back to the ship to sort out what's going on.

It turns out the problem was due to a transporter accident. Eight years ago while Riker beamed back to his ship, part of the transporter energy beam made it to the ship, where Riker rematerialized, but part of the energy beam was deflected back to the planet's surface, where another Riker materialized. But everyone in the ship, including the successfully beamed Riker, figured the transport worked, and so the ship's crew and all the universe went on with business, unaware of the second Riker doomed to playing Robinson Crusoe on the planet below.

That raises the question: Are both Rikers the same Riker?

It's hard to see how they're the same, and indeed the show plays to that conclusion. Without giving too much away, by the episode's end the second Riker gets an assignment on a different ship and has decided to change his name from William to Thomas, his middle name. But the show also shows how Tom Riker is very much like Will Riker by way of Tom romantically rejecting Counselor Deanna Troi to instead focus on his career, just as Will Riker had rejected her eight years previously.

Back to physicalism. The problem duplication presents for physicalism is that if, as according to physicalism, a person is nothing more than a body, then there should be something purely corporeal to account for what makes the two Rikers different. The quick answer is that there is such a difference. Will Riker spent eight years normally, serving as a Star Fleet officer; meanwhile, the other Riker, Tom, spent eight years alone and abandoned on the surface of Nervala IV. It's remarkable Tom didn't go insane, given such a lengthy solitary existence, and in any event the two Rikers now have enough sufficiently different experiences to be different people—to have different thoughts, desires, goals, etc.

But that answer ignores the moment when both Rikers rematerialized, one in the ship and one on the planet's surface, back when they had the same experiences, thoughts, desires, goals, etc. Were the two Rikers the same person at that moment? Presumably the two Rikers, if they were ever the same person, forked in identity as soon as their sensory organs took in different input: different sights, different sounds, different smells, etc. From that moment on the two Rikers diverged physiologically and thus became different people. But in that one moment after the split but before differentiation, were the two Rikers the same person?

It's a fun question to ponder. But I think that it, like the two analogies I wrote about last week, misses the point.

Bartlett Lake overnighter: lessons learned

My original intention was to ride twice as far, east into mining country. That trip would have had me ride twenty miles on unpaved road through the Superstition Mountains, sleep alongside a highway, and achieve a personal best in burrito-eating. But the Arizonan economy has been unkind to burrito restaurants, with the proximate effect of Big Burrito shutting down its Miami, AZ location and the ultimate effect of me biking instead to Bartlett Lake for my overnighter. It's just as well: The trip proved a good test run, and there are other Mexican food restaurants to eat at.

Here are a few lessons I learned:

• Use lighter, thinner tires. When commuting to and from work, I use nearly-invulnerable-but-slow-rolling tires that cost me a few minutes each day but in return reduce the odds that I'll sometimes lose fifteen minutes to change a flat. It's a worthwhile trade because it optimizes for predictability. But on a long bike trip, that extra predictability is a waste of calories. Not only do those "few minutes" lost add up to a lot of time, but changing a flat may make for a welcome break off the saddle. I estimate the Schwalbe Marathon Plus tires I used made the Bartlett Lake trip 10-20% longer, virtually.

• Increase water-storing capacity. I left the town of Cave Creek Saturday afternoon carrying one pint shy of a gallon. I returned to Cave Creek Sunday morning with only one pint remaining. That's a consumption of three quarts—over the course of a cool February evening and night. If I'm going to do a trip in the desert in the spring or fall then I'll need to be able to carry several gallons. This means adding more bottle cages, wearing a backpack with a bladder, and storing more water in the panniers.

• Buy a camera. I lost my camera over a year ago when I left it behind at a restaurant. Now I don't have a good way to document my bike adventures. Instead, I have only these words.

Physicalism and resurrection

Those of us who don't believe in souls have some explaining to do. Without a soul to identify what a person is, we're left with only the person's body and the physical stuff it comprises. But that's not the whole story—there are loose ends. Some of those loose ends came up in Kagan's Philosophy of Death class, the first half of which covers a collection of theories and arguments about personal identity. Though Kagan himself is settled as a physicalist, and thus rejects the existence of souls, he acknowledges that his arguments leave open many questions.

One problem for physicalists has to do with our notion of resurrection. According to one version of physicalism, resurrection entails nothing more than reconstructing a body identical to that of a body from the past—presumably the body of someone now dead. Such a reconstruction could be the result of a Star-Trek-like replicator device, which conjures physical things from raw materials. After replicating a body, the body's corresponding person would be brought back into existence. Or would it? Here are two analogies of bodily reconstruction that lead to different answers to that question.

Analogy #1, the bicycle

(In his class, Kagan uses an example of a watch, but I prefer to use a bike because I know more about bikes.)

Imagine you have a bicycle. You take the bicycle to a mechanic to have it overhauled. As part of the overhaul, the mechanic will take the bike completely apart to clean the parts and possibly replace some parts. He'll strip everything from the frame—wheels, chain, gears, cranks, brakes, cables, shifters, etc. After having cleaned or replaced each part, he'll put the bike back together to make a bike nearly as good as new.

But midway through the overhaul, the mechanic spots a problem. He phones you during lunch and says your cassette shows signs of wear, do you want to have it replaced? You're wary of the bike shop and wonder if the mechanic is trying to overcharge you by selling you unneeded parts, and so you respond that you'll stop by the store that afternoon and take a look yourself. Later that day, in the bike shop, the mechanic greets you and shows you your bike. It consists of a frame, fork, handlebars, and wheels lying in a heap on the floor and the other components in a cardboard box on the counter. Where's my bike? you ask.

Right here, say the mechanic, pointing to the heap on the floor. "And there," then pointing to the box on the counter.

That's no bicycle, you say. That's just a bunch of bike parts.

Well, yeah, it's your bike midway through an overhaul, responds the mechanic. By the way, your shifters are gunked up. You want to just upgrade your whole drive chain? We have a special deal on Campy—

—But the shifters were working fine when I brought the bike in… And so you drop the ontology argument and instead argue with the mechanic to keep your original parts (and a smaller bill). The next day, overhaul completed and a new cassette installed, you go to the shop and retrieve your bike, restored to full form from the mere heaps of parts it was the previous day.

In summary: Take a bike, strip it down to bare parts, clean some and replace others, and then put the bike back together: same bike.

Analogy #2, the block tower

A four-year-old boy builds a massive tower out of toy blocks in the living room. He's proud of his achievement and shows his dad, who's impressed with his young son's promising architectural skills. But alas, it's past the boy's bedtime, and the dad says as much.

But can't I show Mom my tower? the boy asks.

No, kiddo, it's bedtime, says Dad, and Mom is out with her friends till late tonight. I tell you what: I promise I'll show Mom your tower as soon as she gets home. Now, off to bed.

Father and son walk to the boy's bed, where Dad tucks the boy in. On the way back to the couch in the living room, when passing by the tower, Dad accidentally kicks a key block at the tower's base, causing the entire tower to fall over, sending blocks scattering across the floor, the tower now thoroughly destroyed. Oh no! Dad thinks. I just promised him I would show Mom that tower.

Fortunately, Dad took a photo of the tower before its untimely destruction, back when the boy was showing it off. Gathering the scattered blocks, and using the photo, Dad constructs a tower identical to the one his son made an hour ago. He places the base of the tower in the same spot on the floor, and he meticulously chooses blocks of the right color and shape to match the blocks in the photo. After a few hours of careful reconstruction work, Dad finishes the tower, just as the front door opens and Mom walks through the door. What's that? she asks.

That's a tower our son made. Isn't it wonderful?

Here, many people will say the dad is lying, or at least not being truthful. The son didn't make that tower; he make a tower that was knocked over and no longer exists. The new tower, however much a facsimile of the original tower, is a different tower than the one the son made.

In summary: Take a block tower, knock it over, and have someone else recreate it: different tower.

Which story?

Which story best matches the resurrection of people's bodies? Is a body like a bike, where taking it apart and putting it back together means the same person is brought back into existence? Or is a body like a block of towers, where if destroyed and brought back into existence a new person is created?

My own interpretation is that both analogies fall short—for a reason I'll discuss in a future blog post. But if I had to choose from the two choices here—bike or tower—I would say that a body is more like a bike. I would think the summary from the second analogy is wrong: that the tower built by the dad is indeed the same tower built by the son. The tower isn't defined by who constructed (or reconstructed) it; rather, the tower is defined by what it is.

But what I find most interesting is how both analogies fail.

Stop

Yet again in Arizona there's a proposed law to allow cyclists to treat stop signs as yield signs. This isn't the first time this change his been proposed and killed, so there's reason to doubt its passage. But if the bill does pass, it won't change much in the real world: most cyclists treat most stop signs as yield signs already, so the effect of the bill would be to decriminalize what cyclists already do, not change their behavior.

I don't advocate that cyclists follow traffic laws. Instead, I advocate that cyclists protect themselves. Usually that means following the law, but sometimes it means breaking the law. In the case of stop signs, I fail to see how coming to a full stop is de facto safer for the cyclist. Rather, I see the opposite. By default, a bicycle is unbalanced when at rest and unwieldy when started from a full stop. Also, unlike motorists, cyclists are vulnerable while stopped in the road; we don't have bumpers and two tons of mass to protect us from rear-end collisions.

But it's not my intention to argue in favor of the law. Yes, I support it because it would decriminalize part of my behavior, but the practical effect would be small: I've never been ticketed for running a stop sign—and that's not for lack of police witness.

Legally, a bicycle is a vehicle, and cyclists are subject to most of the same laws as motorists. However, in the real world, cyclists constitute a tiny minority of traffic and are mostly left alone by law enforcement. The unwritten rule for cyclists is: stay off the busy roads and don't cause trouble, and the police will leave you alone. It's the kind of just privilege that history often affords tiny, voiceless minorities, and it's as it should be.

But I fear someday cycling will catch on and grow from being a voiceless minority into being a vocal minority, and consequently its truce with law enforcement will end. Rather than empowering the cycling community, the result, I predict, would be to spark a backlash from motorists. Roads are built by motorists for motorists, just as traffic law is written by motorists for motorists. Cyclists don't pay gasoline taxes, yet we're tossed 1% of urban road budgets by way of perks such as bike lanes. That fuels resentment from motorists. And we break lots of their laws too; that also fuels resentment.

The greatest danger in being a cyclist is that you're invisible to motorists: they don't see you coming. But we're also invisible to the establishment, and that's our greatest safety.

Writing philosophy

By listening to the two remaining lectures this morning, I completed my audit of Shelly Kagan's Philosophy of Death class that Shafik recommended to me a year ago. The lectures are freely available as both video and audio-only clips recorded from the spring 2007 semester Kagan taught at Yale.

Like with a lot of other great philosophical discourses, Kagan's lectures left me with the impression that I didn't learn much. But I know that impression is false; it's just that Kagan is so clear in making his points that everything I learned seemed obvious in hindsight, as though I was merely rediscovering my own knowledge rather than learning anything new. Kagan always has the perfect example to isolate philosophical principles and to exaggerate consequences to absurdity, such as with his example against the two-state requirement.

The two-state requirement has to do with the topic of suicide and whether it ever makes sense to say so-and-so Jones is better off dead. According to the requirement, such statements are always illogical because Jones can be better off following some X only if he's around to experience the effects of X. For example, Jones may be better off learning Spanish because he'll have a before state of not knowing Spanish and an after state of knowing Spanish and he may be better off in the after state than in the before state. But in the case of death, Jones has no after state because after dying Jones doesn't exist. Therefore, Jones can't ever be better off dead.

But against the two-state requirement, Kagan uses the following example.

Imagine that you've got some happy person, some incredibly happy person with a wonderful life filled with whatever goods you think are worth having in life—love and accomplishment and knowledge and whatever it is. He's walking across the street and he's about to get hit by a truck. And so, at some risk to yourself, you leap into the way, pushing him out of the way, saving his life. And happily, you don't get hurt either. He looks up, realizes he was this close from death and he says, Thank you. Thank you for saving my life.

And now what you have to say is, I'm afraid you're rather confused. Because to say thank you for my saving your life is to presuppose I've benefited you in some way. To presuppose I've benefited you in some way is to assume that you're—it's a good thing that your life has continued. But, you see, given the two-state requirement, we can't say it's a good thing that your life continued, because the two-state requirement says we can only make that kind of remark when there's a before state and an after state. And the after state would have been nonexistence. So, you see, you're really rather philosophically confused in thinking that I've done you some sort of favor by saving your life.

Brilliant! No amount of theoretical abstraction will dispel the two-state requirement as well as an example like that. If pictures are worth a thousand words, then examples are worth a thousand arguments.

As I continued listening to the lectures, I became increasingly impressed by Kagan's clear way of talking, and I thought about how to bring that clarity into my own philosophical writing. It's one thing to write clearly about other, less abstract topics, such as some maintenance work I did on my bike or having reinstalled Linux on my laptop. But philosophy is conceptual and thus hard to write about.

But there's more to writing well than merely producing better blog posts. If, as William Zinsser says, clear writing is clear thinking, then one's philosophical ideas are only as good as one's writing. That's the challenge in writing better philosophy.

Funny movies for men and women

Few women appreciate Blazing Saddles for the brilliant movie it is. This isn't Mel Brooks's fault; most comedies appeal unevenly across gender. But there are exceptions.

Here's my tentative list of the five funniest non-romantic comedies that are equally funny to both men and women.

• Groundhog Day
• My Cousin Vinny
• Toy Story, or just about any Pixar or Disney animated movie
• The Princess Bride
• The Mask

Please respond with your own additions or corrections to the list.