CONGRATULATIONS

To Joshua and Neal!

Two fantastic positions. Two great philosophers. Representin' WWU!!!

Spatial and Temporal Zeno Walls

We might be familiar with the following puzzle.  Suppose that there is a football field at the end of an inclined plan.  On the field there are a bunch of walls, each facing the inclined plane.  One wall is at the 50 yard line, another wall closer to the inclined plane, at the 25 yeard line.  Still another wall is even closer to the invlined place at the 12.5 yard line and so one all the way to the end zone.  The walls form a zeno series whose open end is at the end zone at the foot of the inclined plane.  Now, suppose we roll a ball down the inclined plane.  The laws of nature in this world include the law that an object in motion remains in motion.  Moreover, there are no impuritied in the plane that will make the ball deviate from its course toward the zeno series of walls.  Finally, there are no stray objects that will intervene in the balls trajectory.  The ball will make it to the end zone and it will make it all the way to the zeno series of wells.  However, there are also physical laws that prevent the ball from passing through any walls and discontinuously passing through space.  So, the ball must stop before it passes through the end zone.  But, what makes it stop?  It can't be any one of the walls.  After all, if any one of the walls made it stop, then it must have reached that wall.  But, in order for it to reach that wall, it would have to pass through some previous wall.  That, however, is not physically possible.  Hawthorne has suggested that the fusion of the walls stops the balls.  This commits Hawthorne to a liberal view of composition.  I am inclined to say that the walls have irreducibly plural causal powers.  In any case, some thing or things has to stop the ball from moving.  Since there are no other objects in the vacinity, it must be that some walls or fusion of walls stops the ball from moving.  

Here is a new puzzle though.  Suppose that there is a man who is happily persisting through time.  He is healthy and the laws of nature are inconsistent with his sudden and unexpected demise.  However, at 12:20 tomorrow a solid object composed of a single substance and filling all of space comes into existence for a mere instant.  At 12:10 tomorrow, a solid object composed of a single substance and filling all of space comes into existence for a mere instant.  At 12:05 tomorrow, a solid object composed of a single substance and filling all of space comes into existence for a mere instant . . . and so on . . .  There is a zeno series of walls in time whose open end is at 12:00 and no member of which exists before 12:00.  The young healthy man will persist all the way to 12:00.  However, the laws of nature prevent a young healthy man from passing though the solid objects or discontinuously persisting through an interval of time.  So, the young man must stop persisting through time.  In other words, the young man must cease to exist at 12:00, he must die.  But, what stops him from persisting, what makes him cease to exist or die?  Just as before, we might think that the fusion of the walls stops the man from persisting.  But, that commits us to a liberal view of diachronic composition.  In fact, that solution seems to commit us to the existence of something that has temporal parts.  We might say that the walls have irreducibly plural causal powers.  But, then something that doesn't yet exist seems to cause something else to go out of existence.  These are strange consequences.  Nevertheless, something must make the young man cease to exist.  

This last puzzle is particularly troubling for a presentist.  We can describe a world like the one above using only presentist friendly phrases.  There is a man and at 12:20 tomorrow a solid object composed of a single substance that fills all of space will come into existence for an instant.  At 12:10 tomorrow  solid object composed of a single substance that fills all of space will come into existence for an instant . . . The laws of nature guarantee that the young man will make it to 12:00 in perfect health.  However, the young man will not exist after 12:00.  So, it must be that something will make him cease to exist.  But, at no time will there be anything that makes him cease to exist.  So, nothing will make him cease to exist.  But, it cannot be that something will make him cease to exist and yet nothing will make him cease to exist.  Perhaps we have a reason, then, to think that presentism is false.  

Williamson on Judgment Skepticism

In chapter 7, Williamson discusses a type of skepticism he calls judgment skepticism. As he explains it, judgment skepticism "does not target the distinctive features of perception, memory, testimony, or inference" but instead "targets our practices of applying concepts in judgment" (p. 220). Williamson's paradigm example of a judgment skeptic is the person who, with van Inwagen, denies that mountains exist. Since it is the view of these folks that our ordinary geographical judgments are systematically false when understood strictly and literally, they count as judgment skeptics. Williamson then goes on to argue that judgment skepticism is on a par in important ways with skepticism about the external world.

There is some interesting stuff in this chapter about philosophical methodology, but I'm not quite sure what to say about that. So instead I'll raise two issues with the way he construes judgment skeptics like those who deny the existence of inanimate macroscopic objects.

First, he seems to think that judgment skepticism is going to have drastic consequences for the natural sciences. He says:

Judgment skeptical arguments apply to standard perceptual judgments, on which the natural sciences systematically depend: microscopes, telescopes, and other scientific instruments enhance ordinary perception but do not replace it, for we need ordinary perecption to use the instruments. If the contents of those perceptual judgments concern ordinary macroscopic objects, they are vulnerable to judgment skepticism about common sense ontology. If so, the empirical evidence for scientific theories is threatened. To assume that the evidence can be reformulated without relevant loss in ontologically neutral terms, in the absence of any actual such reformulation, would be optimistic to the point of naivety.

Well, perhaps I'm just being naive here, but I feel much more optimistic for such a reformulation project. At least, I don't see any reason to think that it couldn't be successfully carried out. Exactly what drastic consequence would follow for natural science if we agreed with van Inwagen that, strictly speaking, there are no mountains, or even that there are no telescopes? I just don't see it.

Also, he talks about judgment skeptics as though they argue for their position in a way precisely analogous to the more familiar sort of skepticism, but that doesn't seem true to me. As he points out, the skeptic about the external world may well argue employing the following bit of reasoning: since everything would appear to us exactly as it currently appears to us even if we were just brains in a vat, we don't know that we're not. The parallel move in the case of the van Inwagen-style skeptic would be: since it would still appear to us that there were mountains even if there were no mountains, we don't know that there are mountains. Perhaps someone who argued for mountain-skepticism using this sort of reasoning would be open to Williamson's objections, but van Inwagen doesn't argue in this way, does he? I thought the argument was supposed to employ more general mereological considerations about, for example, the downsides of DAUP and Unrestricted Composition, among other things. So it's unclear to me that judgment skepticism really is the sort of view Williamson is painting it to be -- or perhaps eliminativist views like van Inwagen's shouldn't count as versions of judgment skepticism after all?

Lying about PowerPoint

In chapter 6, Williamson says that sometimes when he is teaching his students about Gettier cases, he says certain things to them so that they are actually in a Gettier case themselves. But I'm wondering whether what he says to them actually succeeds in Gettierizing their beliefs. He says he starts off by telling them:

(1) The only time I've used PowerPoint in the past it was a complete disaster.

From this they naturally come to believe:

(2) Williamson has never successfully used PowerPoint.

(2) is in fact true, and they seem to be justified in believing it (given that they have no reason to distrust his testimony in (1)), but they don't know (2) because the belief it represents is based on a lie. In fact, Williamson has never even tried to use PowerPoint and thus he says that (1) is false. Since they base (2) on something false, it looks like they don't know (2) despite the fact that it is a justified true belief.

But is (1) false? I guess it depends on what's being said. If what he is saying is this:

There exists a time at which I used PowerPoint and my using PowerPoint at that time was a disaster,

then it is indeed false. But if what he is saying is this:

Every time I've used PowerPoint in the past it has been a disaster,

then it looks vacuously true given the peculiarity of the universal quantifier.

Of course, maybe what this shows is that Gettier situations can arise even if the belief in question isn't based on a false belief. And, in any case, Williamson could just as well start his classes by saying, "I have used PowerPoint once before and it was a failure". So I'm not questioning the possibility of Gettierizing students...I'm just wondering whether the case as he presented it does the trick, and what it might tell us about Gettier cases even if it does.

Anaphora and Conditionals

Let me say, before I get started, that I am way out of my league when it comes to issues involving anaphora and conditionals. In spite of that fact, I will be expressing a bit of skepticism about Williamson's treatment of conditionals with anaphora.

Williamson takes the following sentence to express one of the primary propositions in a Gettier style argument against the justified true belief account of knowledge:

(5) If a thinker were Gettier related to a proposition, then he/she would have a justified true belief without knowledge.

Williamson wants to formalize this statement. Surprisingly, Williamson's formalization of (5) is the following (again, I hope everyone can figure out my crude notation system. If not, this is intended to be identical to what Williamson labels (3*) in the book):

(3*) ExEp GC(x, p) []--> AxAp (GC(x, p) --> (JTB(x, p) & ~K(x, p)))

I find this a surprising formalization of (5) because it seems to have a lot more quantifiers and conditionals that (5) does. Put another way, (3*) seems to say that if something were in a Gettier situation, then it would be the case that anything in a Gettier situation has justified true belief without knowledge. But, that doesn't seem to be what (5) says. So, it does not seem like (3*) is a correct formalization of (5).

Williamson happens to have a few argument for the claim that (5) is a correct formalization of (3*). To understand Williamson's argument, we need to first have another candidate formalization in front of us. Here it is:

(10) AxAp (GC(x, p) []--> (JTB(x, P & ~K(x, p))

We also need a couple of candidate formalizations of the following monkey sentence:

(13) if an animal escaped from the zoo, it would be a monkey.

Here are the candidate formalizations:

(14) Ax ((animal(x) & Escaped(x)) []--> Monkey(x)

(15) Ex (animal(x) & escaped(x)) []--> Ax ((Animal(x) & Escaped(x)) --> Monkey(x)

Williamson seems to have two arguments. The first argument says that if (10) is the correct formalization of (5), then (14) is the correct formalization of (13). But, (14) is not the correct formalization of (13). So, (10) is not the correct formalization of (5).

The second argument says that if (15) is the correct formalization of (13), then (3*) is the correct formalization of (5). Moreover, (15) is the correct formalization of (13). So, (3*) is the correct formalization of (5).

Williamson seems to think that the sentences are similar enough that their formalizations will have (roughly) the same logical structure. But, this isn't obviously true to me. For instance, it seems like it follows straightfowardly from (5) that if Neal were in a Gettier situation, then Neal would have justified true belief without knowledge. But, it does not seems to follow straightforwardly from (13) that if George had escaped from the zoo, then George would be a monkey. But, if the sentences have the same logical structure, then the inferences would be both be valid.

I have to admit I've been agonizing over these sentences for a while. In fact, I've been agonizing long enough that I think I should have more to say. Unfortunately, I do not. I am unhappy with both the proposed formalizations and I have not been able to think of any plausible alternatives.

Counterpossibles

Sorry I'm late posting on chapter 5...I just finished reading it today. I found this chapter more interesting than the rest of the book so far, but then again I also felt like Williamson was here just doing straightforward modal epistemology instead of furthering the overall project of the philosophy of philosophy. In any case, I like the suggestions he makes connecting the epistemology of counterfactuals with the epistemology of modality.

I'm unconvinced, though, by his responses to the counterpossible objection. The objection is that Williamson is wrong to say that counterfactuals with impossible antecedents are vacuously true since some such counterfactuals are false. For example, suppose you ask me what is the sum of 5 and 7 and I say '11'. Further suppose that I mistakenly think I said '13' and I then go on to assert: "If 5 + 7 were 13 I would have got that sum right." This counterfactual has an impossible antecedent, but it seems straightforwardly false. Since I actually answered '11', I would still have gotten the sum wrong even if 5 + 7 were 13. This seems right to me.

One of Williamson's objections is that when we think through the example, it falls apart. He says: "For example, if 5 + 7 were 13 then 5 + 6 would be 12, and so (by another eleven steps) 0 would be 1, so if the number of right answers I gave were 0, the number of right answers I gave would be 1." But I don't understand what Williamson is saying here. Is he saying that the friend of counterpossibles in this case has to say that if 5 + 7 were 13, then I would have got the sum right, since it would follow from my giving 0 right answers that I did give 1 right answer after all? If this is what he's saying, I'm not sure why the friend of counterpossibles has to follow him in reasoning this way. It's much less clear to me, for example, that if 5 + 7 were 13 then 5 + 6 would be 12, than it is that if 5 + 7 were 13 then I would have got that sum right. Moreover, his objection here seems to rely on the fact that this is a mathematical example. But surely there are plenty of other intuitively false counterpossibles. Suppose, as Joshua does below, that it is impossible for two objects to be co-located. Then isn't the following both false and a counterpossible: "If Joshua's finger and my finger were co-located, then Joshua would be my son"?

Aliens and Ghosts

There are no ghosts haunting our attics and there are no aliens flying in saucers at night. I will assume that we all agree to these claims. Nevertheless, we might wonder what evidence might make us change our minds. I have some strange intuitions that I think others might share. I'd like to present those intuitions and see if there is anything interesting we can learn from the fact that we have those intuitions.

Suppose we learn that there really are skinny gray creatures that fly around in saucers abducting humans and cows; We learn that many of those people who claim to have seen or experienced such events really did have such sights and experiences. However, we also learn that the little gray creatures are actually creatures who evolved on earth; they are creatures who have never left earth, but have lived in secret for thousands of years deep in the ocean. Some of these creatures have traveled far from their majestic cities and have begun observing life on dry land. they travel in their finely constructed saucer shaped aircraft and sometimes they take a human or cow on board for close observation. If we were to learn that all this is true, would we say that there really are aliens flying in saucers at night? It seems to me that we would not. Rather we would say that what we thought were aliens turned out to be something like highly evolved fish.

However, suppose that we learned that there really are human shaped apparitions that move through our houses at night, disturbing our pets and making various noises; we learn that many people who claim to have seen or experienced such events really did have such sights and experiences. However, we learn that the apparitions are actually semi-corporeal creatures who evolved on earth. They were never any spiritual part of any human being, but have lived in secret for thousands of years in various dark places. Some have moved into our attics and move around at night making a little noise and sometimes disturbing our pets. If we were to learn that all this is true, then would we say that there really are ghosts haunting our attics? It seems to me that we would. We would be surprised to learn that ghosts aren't really the spirits of deceased human beings but rather a new life form living amongst us.

So, why do I have different intuitions about the two cases? Why do I think that in the first case we do not learn that there are aliens flying in saucers, but in the second case we do learn that there are ghosts? Moreover, do others share my intuitions?

I have tried to think of a couple of explanations for my different counterfactual judgments. My first idea was that the concepts applied in the two cases might have been introduced in different ways. One might think that the concept of a ghost was introduced into the community by ostension whereas the concept of an alien was introduced by way of a generalization. Thus, particular judgments about ghosts might carry more weight than general judgments and visa versa for judgments about aliens. But, this doesn't seem right. after all, I have no idea how the concept was first introduced into the community.

Perhaps I was introduced to the concept of a ghost by ostension whereas the concept of an alien was introduced by way of a generalization. But, this doesn't seem right. I am willing to bet rather heavily that I was introduced to the concepts in rather similar ways (perhaps via Robert Stack and Unsolved Mysteries). I suppose if I am mistaken, then we can test this hypothesis by introducing the various concepts to children in different ways and then asking them to make counterfactual judgments various cases while employing those concepts.

My second idea was that I have the judgments that I do because I think the concept of an alien is satisfied whereas my concept of a ghost is not. My concept of an alien is probably satisfied by some lifeform on a distant planet. But, I don't think anything satisfies my concept of a ghost. If this fact could explain why I make different judgments, then we should expect people who do believe in ghosts (as in disembodies spirits) to make a different judgment than me about the counterfactual circumstances in the ghost case above. I have done an unscientific survey of one person (who believes in disembodied spirits) and found that this was not the case; my survey participant had the same judgments that I did.

So, I guess I am at a loss. I’d like to know if any of you have the same judgments that I do and I’d like to know if any of you has an explanation for those judgments.