Philosophy as metaphysics: A very biased view

A Traveling Forms Interpretation of Quantum Mechanics

Paper is here.

Abstract: The Traveling Minds interpretation of Quantum Mechanics is a no-collapse interpretation on which the wavefunction evolves deterministically like in the Everett branching multiple-worlds interpretation. As in the Many Minds interpretation, minds navigate the Everett branching structure following the probabilities given by the Born rule. However, in the Traveling Minds interpretation (a variant by Squires and Barrett of the single-mind interpretation), the minds are guaranteed to all travel together--they are always found in the same branch.

The Traveling Forms interpretation extends the Traveling Minds interpretation in an Aristotelian way by having forms of non-minded macroscopic entities that have forms, such as plants, lower animals, bacteria and planets, travel along the branching structure together with the minds. As a result, while there is deterministic wavefunction-based physics in the branches without minds, non-reducible higher-level structures like life are found only in the branch with minds.

Ontological grounding nihilism

Some people are attracted to nihilism about proper parthood: no entity has proper parts. I used to be rather attracted to that myself, but I am now finding that a different thesis fits better with my intuitions: no entity is (fully) grounded. Or to put it positively: only fundamental entities exist.

This has some of the same consequences that nihilism about proper parthood would. For instance, on nihilism about proper parthood, there are no artifacts, since if there were any, they'd have proper parts. But on nihilism about ontological grounding, we can also argue that there are no artifacts, since the existence of an artifact would be grounded in social and physical facts. Moreover, nihilism about ontological grounding implies nihilism about mereological sum: for the existence of a mereological sum would be grounded in the existence of its proper parts. However, nihilism about ontological grounding is compatible with some things having parts--but they have to be things that go beyond their parts, things whose existence is not grounded in the existence and relations of their parts.

The direction of fit for belief

It’s non-instrumentally good for me to believe truly and it’s non-instrumentally bad for me to believe falsely. Does that give you non-instrumental reason to make p true?

Saying “Yes” is counterintuitive. And it destroys the direction-of-fit asymmetry between beliefs and desires.

But it’s hard to say “No”, given that surely if something is non-instrumentally good for me, you thereby have have non-instrumental reason to provide it.

Here is a potential solution. We sometimes have desires that we do not want other people to take into account in their decision-making. For instance, a parent might want a child to become a mathematician, but would nonetheless be committed to having the child to decide on their life-direction independently of the parent’s desires. In such a case, the parent’s desire that the child become a mathematician might provide the child with a first-order reason to become a mathematician, but this reason might be largely or completely excluded by the parent’s higher-order commitment. And we can explain why it is good to have such an exclusion: if a parent couldn’t have such an exclusion, she’d either have to exercise great self-control over her desires or would have to have hide them from their children.

Perhaps we similarly have a blanket higher-order reason that excludes promoting p on the grounds that someone believes p. And we can explain why it is good to have such an exclusion, in order to decrease the degree of conflict of interest between epistemic and pragmatic reasons. For instance, without such an exclusion, I’d have pragmatic reason to avoid pessimistic conclusions because as soon as we came to them, we and others would have reason to make the conclusions true.

By suggesting that exclusionary reasons are more common than I previously thought, this weakens some of my omnirationality arguments.

My new toy

I've acquired a 3D printer (a used DaVinci 1.0a, hacked by the previous user to have custom firmware), and I've been having fun with it. I still don't have the ideal printing parameters figured out (ABS works OK, but PLA is dodgy, because the printer wasn't designed for it--I had to add a heat sink to help it), but I'm learning how to design 3D solid objects.

I've been finding graphical 3D design tools like Sketchup and Fusion 360 highly unintuitive--maybe with more practice I can improve--but I've also come across OpenSCAD where one uses a simple programming language to code shapes, and that is much more intuitive to me. Last night I designed and printed a super-simple collimator box for the laser collimator for my telescope. Rotating, drawing and dragging faces would have been a big nuisance, but it was a simple bit of code, and it's easily customizable for other dimensions of laser.

Cessation of existence and theories of persistence

Suppose I could get into a time machine and instantly travel forward by a hundred years. Then over the next hundred (external) years I don’t exist. But this non-existence is not intrinsically a harm to me (it might be accidentally a harm if over these ten years I miss out on things). So a temporary cessation of existence is not an intrinsic harm to me. On the other hand, a permanent cessation of existence surely is an intrinsic harm to me.

These observations have interesting connections with theories of persistence and time. First, observe that whether a cessation of existence is bad for me depends on whether I will come back into existence. This fits neatly with four-dimensionalism and less neatly with three-dimensionalism. If I am a four-dimensional entity, it makes perfect sense that as such I would have an overall well-being, and that this overall well-being should depend on the overall shape and size of my four-dimensional life, including my future life. Hence it makes sense that whether I undergo a permanent or impermanent cessation of existence makes a serious difference to me.

But suppose I am three-dimensional and consider these two scenarios:

1. In 2017 I will permanently cease to exist.

2. In 2017 I will temporarily cease to exist and come back into existence in 2117.

I am surely worse off in (1). But if I am three-dimensional, then to be worse off, I need to be worse off as a three-dimensional being, at some time or other. Prior to 2117, I’m on par as a three-dimensional being in the two scenarios. So if there is to be a difference in well-being, it must have something to do with my state after 2117.

But it seems false that, say, in 2118, I am worse off in (1) than in (2). For how can I be better or worse off when I don’t exist?

The three-dimensionalist’s best move, I think, is to say that I am actually worse off prior to 2017 in scenario (1) than in scenario (2). For, prior to 2017, it is true in scenario (1) that I will permanently cease to exist while in (2) it is false that I will do so.

It can indeed happen that one is worse off at time t₁ in virtue of how things will be at a later time t₂. Perhaps the athlete who attains a world-record that won’t be beaten for ten years is worse off at the time of the record than the athlete who attains a world-record that won’t be beaten for a hundred years. Perhaps I am worse off when publishing a book that will be ignored than when publishing a book that will be taken seriously. But these are differences in external well-being, like the kind of well-being we have in virtue of our friends doing badly or well. And it is counterintuitive that permanent cessation of existence is only a harm to one’s external well-being. (The same problem afflicts Thomas Nagel’s theory that the badness of death has to do with unfinished projects.)

The problem is worst on open future views. For on open future views, prior to the cessation of existence there may be no fact of the matter of whether I will come back into existence, and hence no difference in well-being.

The problem is also particularly pressing on exdurantist views on which I am a three-dimensional stage, and future stages are numerically different from me. For then the difference, prior to 2017, between the two scenarios is a difference about what will happen to something numerically different from me.

The problem is also particularly pressing on presentist and growing block views, for it is odd to say that I am better or worse off in virtue of non-existent future events.

Of the three-dimensionalists, probably the best off is the eternalist endurantist. But even there the assimilation of the difference between (1) and (2) to external well-being is problematic.

Progress

I was doing logic problems on the board in class and thinking about rock climbing, and I was struck by the joy of knowing one's made progress on a finite task. You can be pretty confident that if you've got an existential premise and you've set up an existential elimination subproof then you've made progress. You can be pretty confident that if you've got to a certain position on the wall and there is no other way to be at that height then you've made progress. And there is a delight in being really confident that one has made progress.

Moreover, the value of the progress doesn't seem here to be merely instrumental. Even if in the end you fail, still having made progress feels valuable in and of itself. One can try to say that what's valuable is the practice one gets, or what the progress indicates about one's skills, but that doesn't seem right. It seems that the progress itself is valuable. Of course, it has to be genuine progress, not mere going down a blind alley (though recognizing a blind alley, in a scenario where there are only finitely many options, is itself progress).

The value of progress (as such) at a task derives from the value of fulfilling the task, much as the value of striving at a task derives from the value of fulfilling it. But in both cases this is not a case of end-to-means value transfer. Maybe this has something to do with the idea developed by Robert M. Adams of standing for a good. Striving and a fortiori progress are ways of standing and moving in favor of a task. And that's worthwhile even if one does not accomplish the task.

Realism and anti-reductionism

The ordinary sentence "There are four chairs in my office" is true (in its ordinary context). Furthermore, its being true tells us very little about fundamental ontology. Fundamental physical reality could be made out of a single field, a handful of fields, particles in three-dimensional space, particles in ten-dimensional space, a single vector in a Hilbert space, etc., and yet the sentence could be true.

An interesting consequence: Even if in fact physical reality is made out of particles in three-dimensional space, we should not analyze the sentence to mean that there are four disjoint pluralities of particles each arranged chairwise in my office. For if that were what the sentence meant, it would tell us about which of the fundamental physical ontologies is correct. Rather, the sentence is true because of a certain arrangement of particles (or fields or whatever).

If there is such a broad range of fundamental ontologies that "There are four chairs in my office" is compatible with, it seems that the sentence should also be compatible with various sceptical scenarios, such as that I am a brain in a vat being fed data from a computer simulation. In that case, the chair sentence would be true due to facts about the computer simulation, in much the way that "There are four chairs in this Minecraft house" is true. It would be very difficult to be open to a wide variety of fundamental physics stories about the chair sentence without being open to the sentence being true in virtue of facts about a computer simulation.

But now suppose that the same kind of thing is true for other sentences about physical things like tables, dogs, trees, human bodies, etc.: each of these sentences can be made true by a wide array of physical ontologies. Then it seems that nothing we say about physical things rules out sceptical scenarios: yes, I know I have two hands, but my having two hands could be grounded by facts about a computer simulation. At this point the meaningfulness of the sceptical question whether I know I am not a brain in a vat is breaking down. And with it, realism is breaking down.

In order for the sceptical question to make sense, we need the possibility of saying things that cannot simply be made true by a very wide variety of physical theories, since such things will also be made true by computer simulations. This gives us an interesting anti-reductionist argument. If the statement "I have two hands" is to be understood reductively (and I include non-Aristotelian functionalist views as reductive), then it could still be literally true in the brain-in-a-vat scenario. But if anti-reductionism about hands is true, then the statement wouldn't be true in the brain-in-a-vat scenario. And so I can deny that I am in that scenario simply by saying "I have two hands."

But maybe I am moving too fast here. Maybe "I have two hands" could be literally true in a brain-in-a-vat scenario. Suppose that the anti-reductionism consists of there being Aristotelian forms of hands (presumably accidental forms). But if, for all we know, the form of a hand can inform a bunch of particles, a fact about a vector or the region of a field, then the form of a hand can also inform an aspect of a computer simulation. And so, for all we know, I can literally and non-reductively have hands even if I am a brain in a vat. I am not sure, however, that I need to worry about this. What is important is form, not the precise material substrate. If physical reality is the memory of a giant computer but it isn't a mere simulation but is in fact informed by a multiplicity of substantial and accidental forms corresponding to people, trees, hands, hearts, etc., and these forms are real entities, then the scenario does not seem to me to be a sceptical scenario.

Accretion, excretion and four-dimensionalism

Suppose we are four-dimensional. Parthood simpliciter then is an eternal relation between, typically, four-dimensional entities. My heart is a four-dimensional object that is eternally a part of me, who am another four-dimensional object.

But there is surely also such a thing as having a part at a time t. Thus, in utero my umbilical cord was a part of me, but it no longer is. What does it mean to have a part at a time? Here is the simplest thing to say:

1. x is a part of y at t if and only if x is a part of y and both x and y exist at t.

But (1) then has a very interesting metaphysical consequence that only a few Aristotelian philosophers endorse: parts cannot survive being accreted by or excreted from the whole. For if, say, my finger survived its removal from the whole (and not just because I became a scattered object), there would be a time at which my finger would exist but wouldn’t be a part of me. And that violates (1) together with the eternality of parthood simpliciter.

This may seem to be a reductio of (1). But if we reject (1), what do we put in its place, assuming four-dimensionalism? I suspect we will have to posit a second relation of parthood, parthood-at-a-time, which is not reducible to parthood simpliciter. And that seems to be unduly complex.

So I propose that the four-dimensionalist embrace (1) and conclude to the thesis that parts cannot survive their accretion or excretion.

Dualist survivalism

According to dualist survivalism, at death our bodies perish but we continue to exist with nothing but a soul (until, Christians believe, the resurrection of the dead, when we regain our bodies).

A lot of the arguments against dualist survivalism focus on how we could exist as mere souls. First, such existence seems to violate weak supplementation: my souls is proper part of me, but if the body perished, my soul would be my only part—and yet it would still be a proper part (since identity is necessary). Second, it seems to be an essential property of animals that they are embodied, an essential property of humans that they are animals, and an essential property of us that we are humans.

There are answers to these kinds of worries in the literature, but I want to note that things become much simpler for the dualist survivalist if she accepts a four-dimensionalism that says that we are four-dimensional beings (this won't be endurantist, but it might not be perdurantist either).

First, there will be a time t after my death (and before the resurrection) such that the only proper part of mine that is located at t is my soul. However, the soul won’t be my only part. My arms, legs and brain are eternally my parts. It’s just that they aren’t located at t, as the only proper part of me that is located at t is my soul. There is no violation of weak supplementation. (We still get a violation of weak supplementation for the derived relation of parthood-at-t, where x is a part-at-t of y provided that x is a part of y and both x and y exist at t. But why think there is weak supplementation for parthood-at-t? We certainly wouldn’t expect weak supplementation to hold for parthood-at-z, where z is a spatial location and x is a part-at-z of y provided that x is a part of y and both x and y are located at z.)

Second, it need not follow from its being an essential property of animals that they are embodied that they have bodies at every time at which they exist. Compare: It may be an essential property of a cell that it is nucleated. But the cell is bigger spatially than the nucleus, so it had better not follow that the nucleus exists at every spatial location at which the cell does. So why think that the body needs to exist at every temporal location at which the animal does? Why can’t the animal be bigger temporally than its body?

Of course, those given to three-dimensional thinking will say that I am missing crucial differences between space and time.

Three strengths of desire

Plausibly, having satisfied desires contributes to my well-being and having unsatisfied desires contributes to my ill-being, at least in the case of rational desires. But there are infinitely many things that I’d like to know and only finitely many that I do know, and my desire here is rational. So my desire and knowledge state contributes infinite misery to me. But it does not. So something’s gone wrong.

That’s too quick. Maybe the things that I know are things that I more strongly desire to know than the things that I don’t know, to such a degree that the contribution to my well-being from the finite number of things I know outweighs the contribution to my ill-being from the infinite number of things I don’t know. In my case, I think this objection holds, since I take myself to know the central truths of the Christian faith, and I take that to make me know things that I most want to know: who I am, what I should do, what the point of my life is, etc. And this may well outweigh the infinitely many things that I don’t know.

Yes, but I can tweak the argument. Consider some area of my knowledge. Perhaps my knowledge of noncommutative geometry. There is way more that I don’t know than that I know, and I can’t say that the things that I do know are ones that I desire so much more strongly to know than the ones I don’t know so as to balance them out. But I don’t think I am made more miserable by my desire and knowledge state with respect to noncommutative geometry. If I neither knew anything nor cared to know anything about noncommutative geometry, I wouldn’t be any better off.

Thinking about this suggests there are three different strengths in a desire:

1. S_p: preferential strength, determined by which things one is inclined to choose over which.

2. S_h: happiness strength, determined by how happy having the desire fulfilled makes one.

3. S_m: misery strength, determined by how miserable having the desire unfulfilled makes one.

It is natural to hypothesize that (a) the contribution to well-being is S_h when the desire is fulfilled and −S_m when it is unfulfilled, and (b) in a rational agent, S_p = S_h + S_m. As a result of (b), one can have the same preferential strength, but differently divided between the happiness and misery strengths. For instance, there may be a degree of pain such that the preferential strength of my desire not to have that pain equals the preferential strength of my desire to know whether the Goldbach Conjecture is true. I would be indifferent whether to avoid the pain or learn whether the Goldbach Conjecture is true. But they are differently divided: in the pain case S_m >> S_h and in the Goldbach case S_m << S_h.

There might be some desires where S_m = 0. In those cases we think “It would be nice…” For instance, I might have a desire that some celebrity be my friend. Here, S_m = 0: I am in no way made miserable by having that desire be unfulfilled, although the desire might have significant preferential strength—there might be significant goods I would be willing trade for that friendship. On the other hand, when I desire that a colleague be my friend, quite likely S_m >> 0: I would pine if the friendship weren’t there.

(We might think a hedonist has a story about all this: S_h measures how pleasant it is to have the desire fulfilled and S_m measures how painful the unfulfilled desire is. But that story is mistaken. For instance, consider my desire that people not say bad things behind my back in such a way that I never find out. Here, S_m >> 0, but there is no pain in having the desire unfulfilled, since when it’s unfulfilled I don’t know about it.)

"Should know"

I’ve been thinking about the phrase “x should know that s”. (There is probably a literature on this, but blogging just wouldn’t be as much fun if one had to look up the literature!) We use this phrase—or its disjunctive variant “x knows or should know that s”—very readily, without its calling for much evidence about x.

• “As an engineer Alice should know that more redundancy was needed in this design.”

• “Bob knows or should know that his behavior is unprofessional for a librarian.”

• “Carl should have known that genocide is wrong.”

Here’s a sense of “x should know that s”: x has some relevant role R and it is normal for those in R to know that s under the relevant circumstances. In that sense, to say that x should know that s we don’t need to know anything specific about x’s history or mental state, other than that x has role R. Rather, we need to know about R: it is normal engineering practice to build in sufficient redundancy; librarians have an unwritten code of professional behavior; human beings normally have a moral law written in their hearts.

This role-based sense of “should know” is enough to justify treating x as a poor exemplar of the role R when x does not in fact know that s. When R is a contingent role, like engineer or librarian, it could be a sufficient for drumming x out of R.

But we sometimes seem use a “should know” claim to underwrite moral blame. And the normative story I just gave about “should know” isn’t strong enough for that. Alice might have had a really poor education as an engineer, and couldn’t have known better. If the education was sufficiently poor, we might kick her out of the profession, but we shouldn’t blame her morally.

Carl, of course, is a case apart. Carl’s ignorance makes him a defective human being, not just a defective engineer or librarian. Still a defective human being is not the same as a morally blameworthy human being. And in Carl’s case we can’t drum him out of the relevant role without being able to levy moral blame on him, as drumming him out of humanity is, presumably, capital punishment. However, we can lock him up for the protection of society.

On the other hand, we could take “x should know that s” as saying something about x’s state, like that it is x’s own fault if x doesn’t know. But in that case, I think people often use the phrase without sufficient justification. Yes, it’s normal to know that genocide is wrong. But we live in a fallen world where people can fall very far short of what is normal through no fault of their own, by virtue of physical and mental disease, the intellectual influence of others, and so on.

I worry that in common use the phrase “x should know that s” has two rationally incompatible features:

• Our evidence only fits with the role-based normative reading.

• The conclusions only fit with the personal fault reading.

Two senses of "decide"

Suppose:

1. Alice sacrifices her life to protect her innocent comrades.

2. Bob decides that if he ever has the opportunity to sacrifice his life to protect his innocent comrades, he’ll do it.

We praise Alice. But as for Bob, while we commend his moral judgment, we think that he is not yet in the crucible of character. Bob’s resolve has not yet been tested. And it’s not just that it hasn’t been tested. Alice’s decision not only reveals but also constitutes her as a courageous individual. Bob’s decision falls short both in the revealing but also in the constituting department (it’s not his fault, of course, that the opportunity hasn’t come up).

Now compare Alice and Bob to Carl:

3. Carl knows that tomorrow he’ll have the opportunity to sacrifice his life to protect his innocent comrades, and he decides he will make the sacrifice.

Carl is more like Bob than like Alice. It’s true that Carl’s decision is unconditional while Bob’s is conditional. But even though Carl’s decision is unconditional, it’s not final. Carl knows (at least on the most obvious way of spelling out the story) that he will have another opportunity to decide come tomorrow, just as Bob will still have to make a final decision once the opportunity comes up.

I am not sure how much Bob and Carl actually count as deciding. They are figuring out what would or will (respectively) be the thing to do. They are making a prediction (hypothetical or future-oriented) about their action. They may even be trying by an act of will to form their character so as to determine that they would or will make the sacrifice. But if they know how human beings function, they know that their attempt is very unlikely to be successful: they would or will still have a real choice to make. And in the end it probably wouldn’t surprise us too much if, put to the test, Bob and Carl failed to make the sacrifice.

Alice did something decisive. Bob and Carl have yet to do so. There is an important sense in which only Alice decided to sacrifice her life.

The above were cases of laudable action. But what about the negative side? We could suppose that David steals from his employer; Erin decides that she will steal if she has the opportunity; and Frank knows he’ll have the opportunity to steal and decides he’ll take it.

I think we’ll blame Erin and Frank much more than we’ll praise Bob and Carl (this is an empirical prediction—feel free to test it). But I think that’s wrong. Erin and Frank haven’t yet gone into the relevant crucible of character, just as Bob and Carl haven’t. Bob and Carl may be praiseworthy for their present state; Erin and Frank may be blameworthy for theirs. But the praise and the blame shouldn’t go quite as far as in the case of Alice and David, respectively. (Of course, any one of the six people might for some other reason, say ignorance, fail to be blameworthy or praiseworthy.)

This is closely to connected to my previous post.

Two senses of "intend"?

Consider these sentences:

1. Intending to kill the wolverine, Alice pulled the trigger

and:

2. Intending to get to the mall, Bob started his car.

If Alice pulls the trigger intending to kill the wolverine and the wolverine survives, then necessarily Alice’s action is a failure.

But suppose that Bob intends to get to the mall, starts his car, changes his mind, and drives off for a hike in the woods. None of the actions described is a failure. He just changed his mind.

If nanoseconds after the bullet leaving the muzzle Alice changed her mind, and it so happens the wolverine survived, it is still true that Alice’s action failed. Given her intention, she tried to kill the wolverine, and failed.

In the change of mind case, Bob, however, didn’t try to get to the mall. Rather, he tried to start to get to the mall, and he also started trying to get to the mall. His trying to start was successful—he did start to get to the mall. But it makes no sense to attribute either success or failure to a mere start of trying.

There seems to be a moral difference, too. Suppose that killing the wolverine and getting to the mall are both wrong (maybe the wolverine is no danger to Alice, and Bob has promised his girlfriend not to go to this mall). Then Alice gets the opprobrium of being an attempted wolverine killer by virtue of (1), while Bob isn’t yet an attempted mall visitor by virtue of (2)—only when he strives to propel his body through the door does he become an attempted mall visitor. Even if killing the wolverine and getting to the mall are equally wrong, Bob has done something less bad—for the action he took in virtue of (2) was open to the possibility of changing his mind, as bringing it to completion would require further voluntary decisions. What Bob did was still wicked, but less so than what Alice did.

Action (1) commits Alice to killing the wolverine: if the wolverine fails to die, Alice is still an attempted wolverine killer. But Bob has undertaken no commitment to visiting the mall by starting the car.

This suggests to me that perhaps “intends” may be used in different senses in (1) and (2). In (1), it may be an “intends” that commits Alice to wolverine killing; in (2), it may be an “intends” that only commits Bob to starting trying to visit the mall. In (1), we have an intending that p that constitutes an action as a trying to bring it about that p.

Conditional vs. means-limited intentions

This morning, I set out to walk to the Philosophy Department. If asked my intention, I might have said that it was to reach the Department. And in actual fact I did reach it. Suppose, however, that as I was walking, my wife phoned me to inform me of a serious family emergency that required me to turn back, and that I did in fact turn back.

Here’s a puzzle. The family emergency in this (fortunately) hypothetical scenario seems to have frustrated my intention to reach the Department. On the other hand, surely I did not intend to reach the Department no matter what. That would have been quite wicked (imagine that I could only reach the Department by murdering someone). If I did not intend to reach the Department no matter what, it seems that my intention was conditional, such as to reach the Department barring the unforeseen. But the unforeseen happened, so my conditional intention wasn’t frustrated—it was mooted. If I intend to fail a student if he doesn’t turn in his homework, and he turns in his homework, my intention is not frustrated. So my intention was frustrated and not frustrated, it seems.

Perhaps rather than my intention being frustrated, it was my desire to reach the Department that was frustrated. But that need not be the case. Suppose, contrary to fact, that I was dreading my logic class today and would have appreciated any good excuse to bail on it. Then either I had no desire to reach the Department or my desire was conditional again: to reach the Department unless I can get out of my logic class. In neither case was my desire frustrated.

Let me try a different solution. I intended to reach the Department by morally licit means. The phone call made it impossible for me to reach the Department by morally licit means—reaching the Department would have required me to neglect my family. My intention wasn’t relevantly conditional, but included a stipulation as to the means. Thus my intention was frustrated when it became impossible for me to reach the Department by morally licit means.

The above suggests that our intentions should generally be thus limited in respect of means, unless the means are explicitly specified all the way down (and they probably never are). Otherwise, our intention wickedly commits us to wicked courses of action in some possible circumstances. Of course, the limitation, just as the intention itself, will typically be implicit.