Skepticism

The Debunkers

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Why are they all blurry?

In a recent article, Michael Shermer says about UFOs:

UFOlogists claim that extraordinary evidence exists in the form of tens of thousands of UFO sightings. But SETI scientist Seth Shostak points out in his book Confessions of an Alien Hunter: A Scientist’s Search for Extraterrestrial Intelligence that this actually argues against UFOs being ETIs, because to date not one of these tens of thousands of sightings has materialized into concrete evidence that UFO sightings equal ETI contact. Lacking physical evidence or sharp and clear photographs and videos, more sightings equals less certainty because with so many unidentified objects purportedly zipping around our airspace we surely should have captured one by now, and we haven’t. And where are all the high-definition photographs and videos captured by passengers on commercial airliners? The aforementioned Navy pilot Ryan Graves told 60 Minutes’ correspondent Bill Whitaker that they had seen UAPs “every day for at least a couple of years.” If true, given that nearly every passenger has a smart phone with a high-definition camera, there should be thousands of unmistakable photographs and videos of these UAPs. To date there is not one. Here, the absence of evidence is evidence of absence.

So you say everything is always vague? There is never any clear evidence?

Richard Carrier accidentally gives the game away when making the same point:

Which leads to the next general principle: notice how real UFO videos (that is, ones that aren’t faked) are always out-of-focus or grainy, fuzzy, or in dim light or infrared or other conditions of extreme ambiguity (you can barely tell even what is being imaged). This is a huge red flag. Exactly as with the errors of human cognition, here we already know we should expect difficulty identifying an object, because we are looking at unclear footage. That “UFOs” always only ever show up in ambiguous footage like this is evidence they are not remarkable. Real alien ships endeavoring to be this visible would have been filmed in much clearer conditions by now. Whereas vehicles able to hide from such filming would never even show up under the conditions of these videos. When you make the conditions so bad you can barely discern obvious things, you have by definition made them so bad you won’t even see less-than-obvious things.

Notice what? “Ones that aren’t faked?” What I notice is that you aren’t actually saying that all UFO reports and videos and so on are vague and unclear. There are plenty of clear ones. You just believe that the clear reports are fake.

Which is fine. You are welcome to believe that. But don’t pretend that all the reports are vague. This drastically reduces the strength of the argument. Your real argument is more or less, “If UFOs were aliens, we would have expected, after all this time, there would be so much evidence that everyone would already have been convinced. But I am not convinced and many people are not convinced. Therefore UFOs must not be aliens.”

Even in its real form, this is not a weak argument. It is actually a pretty good one. It is nonetheless weaker in the case of UFOs than in many other cases where similar arguments are made, because the evidence could easily be reconciled with a situation where the vast majority of UFOs are not aliens, a few or many “clear” cases are hoaxes, and a few clear cases are aliens who typically are attempting to avoid human notice, but who fail or make an exception in a very small number of cases. And in general it is more likely to fail in situations where the phenomena might be very rare, or in situations where something is deliberately hidden (e.g. where there are actual conspiracies.)

The Courage of Robin Hanson

In a sequence of posts beginning around last December, Robin Hanson has been attempting to think carefully about the possibility of UFO’s as aliens. In a pair of posts at the end of March, he first presents a list of facts that would need to be explained under that hypothesis, and then in the next presents his proposal to explain those facts.

In the following post, he makes some comments on fact of having the discussion in the first place:

I’ve noticed that this topic of UFOs makes me feel especially uncomfortable. I look at the many details, and many seem to cry out “there really is something important here.” But I know full well that most people refuse to look at the details, and are quick to denigrate those who do, being confident in getting wide social support when they do.

So I’m forced to choose between my intellectual standards, which say to go where the evidence leads, and my desire for social approval, or at least not extra disapproval. I know which one I’m idealistically supposed to pick, but I also know that I don’t really care as much for picking the things you are supposed to pick as I pretend to myself or others.

We often fantasize about being confronted with a big moral dilemma, so we can prove our morality to ourselves and others. But we should mostly be glad we don’t get what we wish for, as we are often quite wrong about how we would actually act.

This is not merely theoretical. He in fact receives quite a bit of pushback in these posts, some of it rather insulting. For example, in this recent post, someone says in the comments:

When there’s a phenomenon like Bigfoot or the Loch Ness Monster or Alien visitors, believers often point to “all the evidence”. But lots of bad evidence doesn’t equal good evidence! Navy pilots who say they see UFOs “everyday” actually are providing support for the idea that they are misidentifying something mundane. When talking to those who believe in a phenomenon with low plausibility, the best way to start is by saying, “Lets discuss the *single best piece of evidence you have* and then consider other pieces separately.”

I have seen UFO’s twice and each time my brow was furrowed in a vain attempt to understand what I had just witnessed. If I hadn’t simply been lucky enough to see the illusion again from another perspective, each time I would have walked away convinced that I had seen a large, extremely fast craft far away and not a small, slow object quite close to me. And I’m not easy to fool, as I already understand how perspective can be deceiving.

…

I get the idea that your skeptic skills may be under-exercised compared to the rest of your intellect. I’d recommend reading the Shermer book, “Why People Believe Weird Things” or Sagan’s “The Demon Haunted World.” Both are fun reads.

(5ive)

Robin replies,

Your response style, lecturing me about basics, illustrates my status point. People feel free to treat anyone who isn’t on board with full-skeptical like children in need of a lecture.

The debunkers, who are very often the same few people (note that 5ive refers to a book by Michael Shermer), tend to batch together a wide variety of topics (e.g. “Bigfoot or the Loch Ness Monster or Alien visitors”) as “bunk.” You could describe what these things have in common in various ways, but one of the most evident ways is what makes them count as bunk: There is “lots of bad evidence.” That is, as we noted above about UFOs, there is enough evidence to convince some people, but not enough to convince everyone, and the debunkers suppose this situation is just not believable; if the thing were real, they say, everyone would already know.

As I said, this is a pretty good argument, and this generally holds for the sorts of things the debunkers oppose. But this argument can also easily fail, as it did in the case of the meteorites. While people might accept this as a general remark, it nonetheless takes a great deal of courage to suggest that some particular case might be such a case, since as Robin notes, it automatically counts as low status and causes one to be subject to immediate ridicule.

In any case, whether or not the debunkers are right about UFOs or any other particular case, there are at least two general things that they are definitely mistaken about. One is the idea that people who discuss such topics without complete agreement with them are automatically ridiculous. The second will be the topic of another post.

Revisiting Russell on Cause

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We discussed Bertrand Russell’s criticism of the first cause argument here. As I said there, he actually suggests, although without specifically making the claim, that there is no such thing as a cause, when he says:

That argument, I suppose, does not carry very much weight nowadays, because, in the first place, cause is not quite what it used to be. The philosophers and the men of science have got going on cause, and it has not anything like the vitality it used to have.

This is absurd, and it is especially objectionable that he employs this method of insinuation instead of attempting to make an argument. Nonetheless, let me attempt to argue on Russell’s behalf for a moment. It is perhaps not necessary for him to say that there is no such thing as a cause. Suppose he accepts my account of cause as an explanatory origin. Note that this is not purely an objective relationship existing in the world. It includes a specific relationship with our mind: we call something a cause when it is not only an origin, but it also explains something to us. The relatively “objective” relationship is simply that of origin.

A series of causes, since it is also a series of explanations, absolutely must have a first, since otherwise all explanatory force will be removed. But suppose Russell responds: it does not matter. Sure, this is how explanations work. But there is nothing to prevent the world from working differently. It may be that origins, namely the relationship on the objective side, do consist of infinite series. This might make it impossible to explain the world, but that would just be too bad, wouldn’t it? We already know that people have all sorts of desires for knowledge that cannot be satisfied. A complete account of the world is impossible in principle, and even in practice we can only obtain relatively local knowledge, leaving us ignorant of remote things. So you might feel a need of a first cause to make the world intelligible, Russell might say, but that is no proof at all that there is any series of origins with a first. For example, consider material causes. Large bodies are made of atoms, and atoms of smaller particles, namely electrons, protons, and neutrons. These smaller particles are made of yet smaller particles called quarks. There is no proof that this process does not go on forever. Indeed, the series would cease to explain anything if it did, but so what? Reality does not have to explain itself to you.

In response, consider the two following theories of water:

First theory: water is made of hydrogen and oxygen.

Second theory: every body of water has two parts, which we can call the first part and the second part. Each of the parts themselves has two parts, which we can call the first part of the first part, the second part of the first part, the first part of the second part, and the second part of the second part. This goes on ad infinitum.

Are these theories true? I presume the reader accepts the first theory. What about the second? We are probably inclined to say something like, “What does this mean, exactly?” But the very fact that the second theory is extremely vague means that we can probably come up with some interpretation that will make it true, depending in its details on the details of reality. Nonetheless, it is a clearly useless theory. And it is useless precisely because it cannot explain anything. There is no “causality” in the second theory, not even material causality. There is an infinite series of origins, but no explanation, and so no causes.

The first theory, on the other hand, is thought to be explanatory, and to provide material causes, because we implicitly suppose that we cannot go on forever in a similar way. It may be that hydrogen and oxygen are made up of other things: but we assume that this will not go on forever, at least with similar sorts of division.

But what if it does? It is true, in fact, that if it turns out that one can continue to break down particles into additional particles in a relatively similar manner ad infinitum, then “water is made of hydrogen and oxygen” will lose all explanatory force, and will not truly be a causal account, even in terms of material causes, even if the statement itself remains true. It would not follow, however, that causal accounts are impossible. It would simply follow that we chose the wrong account, just as one would be choosing wrongly if one attempted to explain water with the second theory above. The truth of the second theory is irrelevant; it is wrong as an explanation even if it is true.

As I have argued in a number of places, nature is not in the business of counting things. But it necessarily follows from this that it also does not call things finite or infinite; we are the ones who do that. So if you break down the world in such a way that origins are infinite, you will not be able to understand the world. That is not the world’s problem, but your problem. You can fix that by breaking down the world in such a way that origins are finite.

Perhaps Russell will continue to object. How do you know that there is any possible breakdown of the world which makes origins finite? But this objection implies the fully skeptical claim that nothing can be understood, or at least that it may turn out that nothing can be understood. As I have said elsewhere, this particular kind of skeptical claim implies a contradiction, since it implies that the same thing is known and unknown. This is the case even if you say “it might be that way,” since you must understand what you are saying when you say it might be that way.

Kantian and Anti-Kantian Confusion

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I introduced what I called the “Kantian error” in an earlier post, and have since used it in explaining several issues such the understanding of unity and the nature of form. However, considering my original point, we can see that there are actually two relevant errors.

First, there is the Kantian error itself, which amounts to the claim that nothing real can be truly known.

Second, there is an anti-Kantian error, namely the error opposed to the element of truth in Kant’s position. I pointed out that Kant is correct that we cannot know things “as they are in themselves” if this is meant to identify the mode of knowing and the mode of being as such. The opposite error, therefore, would be to say that we can know things by having a mode of knowing which is completely identical to the mode of being which things have. Edward Feser, for example, effectively falls into this error in his remarks on sensible colors discussed in an earlier post on truth in the senses, and more recently at his blog he reaffirms the same position:

Part of the reason the mechanical conception of matter entails the possibility of zombies is that it takes matter to be devoid of anything like color, sound, taste, odor, heat, cold and the like, as common sense conceives of these qualities.  On the mechanical conception, if you redefine redness (for example) as a tendency to absorb certain wavelengths of light and reflect others, then you can say that redness is a real feature of the physical world.  But if by “redness” you mean what common sense understands by it – the way red looks in conscious experience – then, according to the mechanical conception, nothing like that really exists in matter.  And something similar holds of other sensory qualities.  The implication is that matter is devoid of any of the features that make it the case that there is “something it is like” to have a conscious experience, and thus is devoid of consciousness itself.

The implication here is that the way red looks is the way a red thing is. Since the emphasis is in the original, it is reasonable to take this to be identifying the mode of the senses with the mode of being. In reality, as we said in the earlier discussion, there is no “redefinition” because the senses do not define anything in the first place.

Both mistakes, namely both the Kantian and anti-Kantian errors, imply contradictions. The claim that there is something that we cannot know in any way contradicts itself, since it implies that we know of something of which we know nothing. Thus, it implies that an unknown thing is known. Similarly, the claim that the mode of knowing as such is the same as the mode of being, to put it in Kant’s words, “is as much as to imagine that experience is also real without experience.” In other words, suppose that “the way red looks” is the very way a red apple is apart from the senses: then the apple looks a certain way, even when no one is looking, and thus precisely when it does not look any way at all.

Thus both errors imply similar contradictions: an unknown thing as such is known, or a known thing as such is unknown. The errors are generated in much the way Kant himself seems to have fallen into the error. Either knowledge is possible or it is not, we say. If it is not, then you have the Kantian error, and if it is, it appears that our way of knowing must the same as the way things are, and thus you have the anti-Kantian error.

As I pointed out in discussing consistency, an inconsistent claim, understood as such, does not propose to us any particular way to understand the world. The situation described is unintelligible, and in no way tells us what we should expect to find if it turns out to be the case. Given this fact, together with the similarity of the implied contradictions, we should not be surprised if people rarely double down completely on one error or the other, but rather waver vaguely between the two as they see the unpalatable implications of one side or the other.

Thus, the problem arises from the false dichotomy between “knowledge is not possible” and “knowledge is possible but must work in this particular way, namely by an identity of the mode of knowing and the mode of being.” I said in the linked post that this is “one of the most basic causes of human error,” but it might be possible to go further and suggest that it is the principal cause of philosophical error apart from error caused by trading truth for other things. At any rate, the reader is advised to keep this in mind as a distinct possibility. We may see additional relevant evidence as time goes on.

Skeptical Scenarios

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I promised to return to some of the issues discussed here. The current post addresses the implications of the sort of skeptical scenario considered by Alexander Pruss in the associated discussion. Consider his original comparison of physical theories and skeptical scenarios:

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.

If we consider this in light of our analysis of form, it is not difficult to see that Pruss is correct both about the ordinary chair sentence being consistent with a large variety of physical theories, and about the implication that it is consistent with most situations that would normally be considered “skeptical.” The reason is that to say that something is a chair is to say something about its relationships with the world, but it is not to say everything about its relationships. It speaks in particular about various relationships with the human world. And there is nothing to prevent these relationships from co-existing with any number of other kinds of relationships between its parts, its causes, and so on.

Pruss is right to insist that in order for the ordinary sentence to be true, the corresponding forms must be present. But as an anti-reductionist, his position implies hidden essences, and this is a mistake. Indeed, under the correct understanding of form, our everyday knowledge of things is sufficient to ensure that the forms are present: regardless of which physical theories turn out to be true, and even if some such skeptical scenario turns out to be true.

Why are these situations called “skeptical” in the first place? This is presumably because they seem to call into question whether or not we possess any knowledge of things. And in this respect, they fail in two ways, they partially fail in a third, and they succeed in one way.

First, they fail insofar as they attempt to call into question, e.g. whether there are chairs in my room right now, or whether I have two hands. These things are true and would be true even in the “skeptical” situations.

Second, they fail even insofar as they claim, e.g. that I do not know whether I am a brain in a vat. In the straightforward sense, I do know this, because the claim is opposed to the other things (e.g. about the chairs and my hands) that I know to be true.

Third, they partially fail even insofar as they claim, e.g. that I do not know whether I am a brain in a vat in a metaphysical sense. Roughly speaking, I do know that I am not, not by deducing the fact with any kind of necessity, but simply because the metaphysical claim is completely ungrounded. In other words, I do not know this infallibly, but it is extremely likely. We could compare this with predictions about the future. Thus for example Ron Conte attempts to predict the future:

First, an overview of the tribulation:
A. The first part of the tribulation occurs for this generation, beginning within the next few years, and ending in 2040 A.D.
B. Then there will be a brief period of peace and holiness on earth, lasting about 25 years.
C. The next few hundred years will see a gradual but unstoppable increase in sinfulness and suffering in the world. The Church will remain holy, and Her teaching will remain pure. But many of Her members will fall into sin, due to the influence of the sinful world.
D. The second part of the tribulation occurs in the early 25th century (about 2430 to 2437). The Antichrist reigns for less than 7 years during this time.
E. Jesus Christ returns to earth, ending the tribulation.

Now, some predictions for the near future. These are not listed in chronological order.

* The Warning, Consolation, and Miracle — predicted at Garabandal and Medjugorje — will occur prior to the start of the tribulation, sometime within the next several years (2018 to 2023).
* The Church will experience a severe schism. First, a conservative schism will occur, under Pope Francis; next, a liberal schism will occur, under his conservative successor.
* The conservative schism will be triggered by certain events: Amoris Laetitia (as we already know, so, not a prediction), and the approval of women deacons, and controversial teachings on salvation theology.
* After a short time, Pope Francis will resign from office.
* His very conservative successor will reign for a few years, and then die a martyr, during World War 3.
* The successor to Pope Francis will take the papal name Pius XIII.

Even ignoring the religious speculation, we can “know” that this account is false, simply because it is inordinately detailed. Ron Conte no doubt has reasons for his beliefs, much as the Jehovah’s Witnesses did. But just as we saw in that case, his reasons will also in all likelihood turn out to be completely disproportionate to the detail of the claims they seek to establish.

In a similar way, a skeptical scenario can be seen as painting a detailed picture of a larger context of our world, one outside our current knowledge. There is nothing impossible about such a larger context; in fact, there surely is one. But the claim about brains and vats is very detailed: if one takes it seriously, it is more detailed than Ron Conte’s predictions, which could also be taken as a statement about a larger temporal context to our situation. The brain-in-vat scenario implies that our entire world depends on another world which has things similar to brains and similar to vats, along presumably with things analogous to human beings that made the vats, and so on. And since the whole point of the scenario is that it is utterly invented, not that it is accepted by anyone, while Conte’s account is accepted at least by him, there is not even a supposed basis for thinking that things are actually this way. Thus we can say, not infallibly but with a great deal of certainty, that we are not brains in vats, just as we can say, not infallibly but with a great deal of certainty, that there will not be any “Antichrist” between 2430 and 2437.

There is nonetheless one way in which the consideration of skeptical scenarios does succeed in calling our knowledge into question. Consider them insofar as they propose a larger context to our world, as discussed above. As I said, there is nothing impossible about a larger context, and there surely is one. Here we speak of a larger metaphysical context, but we can compare this with the idea of a larger physical context.

Our knowledge of our physical context is essentially local, given the concrete ways that we come to know the world. I know a lot about the room I am in, a significant amount about the places I usually visit or have visited in the past, and some but much less about places I haven’t visited. And speaking of an even larger physical context, I know things about the solar system, but much less about the wider physical universe. And if we consider what lies outside the visible universe, I might well guess that there are more stars and galaxies and so on, but nothing more. There is not much more detail even to this as a guess: and if there is an even larger physical context, it is possible that there are places that do not have stars and galaxies at all, but other things. In other words, universal knowledge is universal, but also vague, while specific knowledge is more specific, but also more localized: it is precisely because it is local that it was possible to acquire more specific knowledge.

In a similar way, more specific metaphysical knowledge is necessarily of a more local metaphysical character: both physical and metaphysical knowledge is acquired by us through the relationships things have with us, and in both cases “with us” implies locality. We can know that the brain-in-vat scenario is mistaken, but that should not give us hope that we can find out what is true instead: even if we did find some specific larger metaphysical context to our situation, there would be still larger contexts of which we would remain unaware. Just as you will never know the things that are too distant from you physically, you will also never know the things that are too distant from you metaphysically.

I previously advocated patience as a way to avoid excessively detailed claims. There is nothing wrong with this, but here we see that it is not enough: we also need to accept our actual situation. Rebellion against our situation, in the form of painting a detailed picture of a larger context of which we can have no significant knowledge, will profit us nothing: it will just be painting a picture as false as the brain-in-vat scenario, and as false as Ron Conte’s predictions.

Thing In Itself

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The last two posts might feel uncomfortably close to total skepticism. “Wait,” you might say, “doesn’t this seem to imply that we don’t know anything about the real world, but only about our experiences?”

We can consider a similar claim with a similar argument, taken from Kant’s Prolegomena to Any Future Metaphysics (§52c):

If I speak of objects in time and space, I am not speaking of things in themselves (since I know nothing of them), but only of things in appearance, i.e. of experience as a distinct way of cognizing objects that is granted to human beings alone. I must not say of that which I think in space or time: that it is in itself in space and time, independent of this thought of mine; for then I would contradict myself, since space and time, together with the appearances in them, are nothing existing in themselves and outside my representations, but are themselves only ways of representing, and it is patently contradictory to say of a mere way of presenting that it also exists outside our representation. The objects of the senses therefore exist only in experience; by contrast, to grant them a self-subsistent existence of their own, without experience or prior to it, is as much as to imagine that experience is also real without experience or prior to it.

There could be a way of understanding this to say something true, but it is more easily understood as asserting something deeply erroneous. Kant may in fact have both the truth and the error in mind, or perhaps he is ambivalent concerning the correct interpretation.

Consider the distinction between the way things are known by us and the way things are in themselves. It is possible to fall into error by asserting that since things are known by us in a certain way, they must be that way in themselves. Thus we know things in a general way, and thus some Platonists might conclude that things exist in themselves in a general way, but this is an error.

But another way to fall into error would be to admit that our way of knowing is distinct from the way of being, and then to conclude from the fact that our way of knowing does not correspond precisely to the way of being, that our knowledge is false, or that we do not know at all. This is the deeply erroneous claim that Kant seems to be making above.

Consider the meaning of the statement: “We know things as they are in themselves.” If we take the phrase, “as they are in themselves,” as expressing our mode of knowing adverbially, just as we might say “We know things in general terms,” and then intend to assert that our mode of knowing is the same as the mode of the being of the thing, then the statement that we know things as they are in themselves is surely false. For the meaning would be that the things exist in our knowledge in exactly the same way as they exist in themselves — thus for example it would be implied that our knowledge is not general but particular. But more precisely, it would imply that there is no distinction whatsoever between our knowledge and the thing. In other words, if we know a horse, our knowledge is actually a horse, physically and literally. And this is manifestly false.

From this we can see both the truth and the error. The truth is that we do not know things as they are in themselves in the above sense, precisely because our knowledge is distinct from the thing known. And the error would be the conclusion that therefore we do not know things at all. Kant seems most clearly to assert the error when he says, “I am not speaking of things in themselves (since I know nothing of them), but only of things in appearance.” The Kantian may insist that this follows necessarily from the truth that we do not know things as they are in themselves in the above sense.

But it is easy to see why this is wrong. We do not know things “as they are in themselves” by having a mode of knowledge identical to the mode of their being. But this does not mean that there is anything that we do not know; in fact, having an identical mode of knowing and being would precisely mean not knowing at all, but being the thing instead. In other words, it does not follow that there is any knowledge that we are missing out on; on the contrary, knowing requires a specific mode of knowing which is different from the mode of being of the thing. It is not that the difference between mode of knowing and being implies that we do not know, but rather this difference is the very condition for knowledge to exist at all. Ayn Rand rightly said of this matter:

Even apart from the fact that Kant’s theory of the “categories” as the source of man’s concepts was a preposterous invention, his argument amounted to a negation, not only of man’s consciousness, but of any consciousness, of consciousness as such. His argument, in essence, ran as follows: man is limited to a consciousness of a specific nature, which perceives by specific means and no others, therefore, his consciousness is not valid; man is blind, because he has eyes—deaf, because he has ears—deluded, because he has a mind—and the things he perceives do not exist, because he perceives them.

Again, the Kantian may insist that perhaps we know the things. But again, we are just admitting we know the things as they appear to us, not as they are in themselves. So even if we know all things, we do not know their mode of being. The response is that we can know both the things and their mode of being, but we know both according to our mode of knowing, not according to their mode of being. This is similar to knowing someone else’s mode of knowing; when you do this, you do not therefore know with their mode of knowing, but with your own. Likewise, when you know the mode of the being of things, you know not with their mode of being, but with your own mode of knowing.

How does this answer our original question? Okay, you might say, there is no proof that there is anything that we cannot know in principle. But in practice it seems clear that our knowledge is entirely superficial, and thus hardly seems to be knowledge at all.

There is a large difference, however, between the assertion, “Most of our actual knowledge is rather superficial,” and the skeptical assertion, “Our knowledge is superficial in principle, and it is therefore impossible to know things as they truly are.” The first assertion is largely correct, and the second is quite wrong. It is true that the understanding of things that we attain “automatically,” as it were, from common experience, is a superficial knowledge, and thus ordinary language about ordinary things expresses such a superficial knowledge. It does not follow that a deep knowledge of things is impossible. However, if someone does not actually have such a deep knowledge, they may also misunderstand what it would even be like to have such a knowledge; and thus for example they might suppose that it would be necessary to have a knowledge of “things in themselves” in the Kantian sense, which of course is impossible, since it would eliminate the distinction between the mode of knowing and the mode of being.

In fact, not only is it not a contradiction to assert that we can know things as they are, but it would be a contradiction to assert, “There is something which we cannot know in any way, even in principle.” For “there is something” purports to refer to the thing and assert its existence, and such reference and assertion, if true, would be a kind of knowledge. Ludwig Wittgenstein makes the similar point, “We cannot think what we cannot think; so what we cannot think we cannot say either.”

It is not, however, a contradiction to say that there are some things that we cannot know in some ways. And this is surely true.

Form and Reality

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In a very interesting post Alexander Pruss discusses realism and skeptical scenarios:

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.

I am not completely sure what Pruss means by “realism is breaking down,” but he is looking at something important here. One question that needs to be addressed, however, is what counts as a skeptical scenario in the first place. In the rest of the post, Pruss makes an interesting suggestion about this:

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.

A skeptical scenario, according to Pruss, is a situation where the things we normally talk about do not have forms. If they do have forms, we are not in a skeptical scenario at all, even if in some sense we are in a computer simulation or even if someone is a brain in a vat. On the face of it this seems a very odd claim: “form” seems to be a technical philosophical explanation, while asking if we are in a skeptical scenario seems to be asking if our everyday common sense understanding of things is mistaken.

Nonetheless, there is a lot of truth in his explanation. First let us consider what is meant by a skeptical scenario in the first place. In terms of his example, it is supposed to go something like this: “Is it possible that you are a brain in a vat without realizing it? If so, then almost everything you believe is false, since you do not have hands, the people you speak to are not real, and so on.”

In the post Pruss is pointing out a problem with the skeptical question. The skeptical question is like a skeptic in the remote past asking, “Is it possible that the earth is spinning without us realizing it? If so, then our everyday opinion that the sun rises every morning is false, since the sun does not move.”

The response to the second skeptic is evident: our everyday opinion that the sun rises every morning is not false, not even if the earth turns out to be spinning, because “the sun rises every morning,” is to be understood in whatever way is needed in order for it to be true. It refers to what happens every morning, whatever that actually happens to be.

Pruss is pointing out that we can answer the first question in the same way: our everyday opinion that we have hands is not false, not even if we are in a computer simulation or in a vat, because “I have two hands” is to be understood in whatever way is needed in order for it to be true. It refers to these two things in front of me right now, whatever they actually are.

Let’s suppose the skeptic tries to come up with a response. He might say, “Look, computer programs do not have hands, and brains do not have hands. So if you are a computer program or a brain in a vat, then you just do not have hands, period. So those scenarios do indeed mean that your common understanding would be false.”

It is certainly true that according to our common understanding, brains in vats do not have hands. So there is a tension here: the argument that it would be true to say we have hands even in that situation seems like a good argument, but so does the argument that it would be false that we have hands.

The answer to the difficulty is that we need to consider the meaning of “I am a brain in a vat.” Just as the word “hands” should refer to these two things in front of me, whatever they are, so the word “brain” refers to things inside of people’s heads, whatever they are, and the word “vat” refers to other things we sometimes experience in real life, at occasionally, or something very like them. But this means that just as “I have two hands” is to be understood in whatever way is needed to make it true, so also “I am not a brain in a vat,” is understood in whatever way is needed to make it true.

This means that correct answer to the original question was simply, “No, it isn’t possible that I will turn out to be a brain in a vat, regardless of any later discoveries, and it isn’t possible that the sun will turn out not to rise, regardless of discoveries about the motion of the sun and of the earth.”

The skeptic will want to insist. Surely events like those of The Matrix are at least conceivable. And if some such situation turned out to be true, then wasn’t it true that you were in a skeptical scenario and that your beliefs about hands and brains and vats were all false, and especially would it not be the case that your belief that you weren’t in a situation like that was false?

The correct answer, again, is that your original beliefs were not false. But in view of your new knowledge of the world, you might well want to adopt a new mode of speaking, and say things that would sound opposed to your original beliefs. They would not be opposed, however, but would simply be speaking about things you did not originally speak about.

Note however that “your belief that you weren’t in a situation like that” could now be taken in two ways. It could mean my belief that I am not a brain in a vat, and this belief will never turn out to have been false. Or it could mean a belief that there is not some larger view of reality where “he was a brain in a vat” would be a reasonable description, in the way that someone coming out of the Matrix would acquire a larger view. In reality I have the latter belief as well, as I consider it improbable that any intelligent beings would behave in such a way as to make that scenario probable. But I don’t think it is impossible for this belief to be falsified; and if it were, I would not say that my previous common sense beliefs had been false. This corresponds to what Pruss says at the end of his post, where he says that as long as things have forms, it is not really a skeptical scenario, even if in some sense he is in a computer simulation or whatever.

Why the insistence on form? This is related to what we called the Semi-Parmenidean Heresy. There we discussed Sean Carroll’s view, and noted that his position in essence is this: Metaphysically, the eliminativists are right. But it is useful to talk as though they are wrong, so we’re going to talk as though they are wrong, and even say they are wrong, by saying that common sense things are real.

This is ultimately incoherent: if the eliminativists are mistaken, they are mistaken in their metaphysics, since the position is just a certain metaphysical position.

It is not difficult to see the connection. According to a strict eliminativist, it would be literally true that we do not have hands, because there is no such thing as “we” or as “hands” in the first place. There are just fundamental particles. In other words, eliminativism would be even more of a skeptical scenario than the Matrix; the Matrix would not imply that your common sense beliefs are false, while eliminativism simply says that all of your beliefs are false, including your belief that you have beliefs.

And on the other hand, no scenario will be truly skeptical, even one like the Matrix, if it admits that our common sense beliefs are true. And as I said at the end of the post on Carroll’s view, this requires a metaphysics that allows those beliefs to be true, and this requires formal causes.

Alexander Pruss, however, seems to me to interpret this in a rather narrow way in his concluding remark:

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.

It is not clear what it means to be “real entities” rather than being unreal, given that you acknowledge them in the first place, and it isn’t clear to me what he means by a “mere simulation.” But this sounds a lot to me like, “If the world isn’t Aristotelian, understood in a very narrow way, then that would be a skeptical scenario.” This seems to me a kind of stubbornness much like that of James Larson. Disagreeing with you is not a war against being, and believing that your account of form and matter didn’t get every detail right, is not saying that our common sense beliefs are not true.

As an illustration of the narrowness in question, consider Pruss’s position on artifacts:

Suppose I am a plumber, and I take a section of pipe, insert a blowgun dart, and blow.  I just shot a dart out of a blowgun.  When did the pipe turn into a blowgun, though?

Did it happen when I formed the intention to use the pipe as a blowgun?  No: I do not have the power to make new material objects come into existence just by thinking about it.

When I picked up the pipe?  There are at least there is contact.  But surely it’s not the right kind of contact.  It would be magic if I could make a new material object come into existence by just picking up a material object with a certain thought in mind.

When I inserted the dart?  Presumably, not any insertion will do, but one with a plan to blow.  For I could just be doing plumbing, using the outer diameter of the dart to measure the inner diameter of the pipe, and that shouldn’t turn the pipe into a dart.  Again, we have some magic here–thinking about the pipe in one way while inserting the dart creates a blowgun while thinking about it another way leaves it a boring pipe.  Moreover, putting the dart into the pipe seems to be an instance of loading a blowgun rather than making a blowgun.

…

The solution to all this is to deny that there are pipes and blowguns.  There is just matter (or fields) arranged pipewise and blowgunwise.  And for convenience we adopt ways of speaking that make it sound like such objects are among the furniture of the universe.

Pruss is not simply putting out a position for discussion; this is what he believes to be true, as is easily confirmed elsewhere on his blog. Note that he is falling into the Semi-Parmenidean heresy here, except that he is even going farther than Carroll, and suggesting that “there are no pipes and blowguns” is a true statement, which Carroll would rightly deny. In this way Pruss is almost a pure eliminativist about artifacts. (He does also speak elsewhere more in the manner of Sean Carroll about them.)

To the degree that he is eliminativist about artifacts, he contradicts common sense in the same kind of way that someone contradicts common sense who says, “You do not have hands.” He just contradicts it about different things. And why about these things, and not others? I suggest that it is because under the ordinary Aristotelian account, it is likely that a man or a horse has a substantial form, but unlikely that a pipe has one. And although a pipe would have various accidental forms, the idea of a unified form of “pipeness” seems pretty unlikely. If this is actually his reason or part of it, then he is identifying skepticism with disagreeing with his philosophical opinions, even though his own opinions actually contain the skepticism: namely, disagreement with common sense.

My own response to this question would be different: being is said in many ways, and consequently also form and unity. And I reject any disagreement with common sense: men and horses are real, but so also are pipes. If I am not mistaken, all of these will have being and form in the way that is appropriate to them.

Semi-Parmenidean Heresy

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In his book The Big Picture, Sean Carroll describes the view which he calls “poetic naturalism”:

As knowledge generally, and science in particular, have progressed over the centuries, our corresponding ontologies have evolved from quite rich to relatively sparse. To the ancients, it was reasonable to believe that there were all kinds of fundamentally different things in the world; in modern thought, we try to do more with less.

We would now say that Theseus’s ship is made of atoms, all of which are made of protons, neutrons, and electrons-exactly the same kinds of particles that make up every other ship, or for that matter make up you and me. There isn’t some primordial “shipness” of which Theseus’s is one particular example; there are simply arrangements of atoms, gradually changing over time.

That doesn’t mean we can’t talk about ships just because we understand that they are collections of atoms. It would be horrendously inconvenient if, anytime someone asked us a question about something happening in the world, we limited our allowable responses to a listing of a huge set of atoms and how they were arranged. If you listed about one atom per second, it would take more than a trillion times the current age of the universe to describe a ship like Theseus’s. Not really practical.

It just means that the notion of a ship is a derived category in our ontology, not a fundamental one. It is a useful way of talking about certain subsets of the basic stuff of the universe. We invent the concept of a ship because it is useful to us, not because it’s already there at the deepest level of reality. Is it the same ship after we’ve gradually replaced every plank? I don’t know. It’s up to us to decide. The very notion of “ship” is something we created for our own convenience.

That’s okay. The deepest level of reality is very important; but all the different ways we have of talking about that level are important too.

There is something essentially pre-Socratic about this thinking. When Carroll talks about “fundamentally different things,” he means things that differ according to their basic elements. But at the same kind the implication is that only things that differ in this way are “fundamentally” different in the sense of being truly or really different. But this is a quite different sense of “fundamental.”

I suggested in the linked post that even Thales might not really have believed that material causes alone sufficiently explained reality. Nonetheless, there was a focus on the material cause as being the truest explanation. We see the same focus here in Sean Carroll. When he says, “There isn’t some primordial shipness,” he is thinking of shipness as something that would have to be a material cause, if it existed.

Carroll proceeds to contrast his position with eliminativism:

One benefit of a rich ontology is that it’s easy to say what is “real”- every category describes something real. In a sparse ontology, that’s not so clear. Should we count only the underlying stuff of the world as real, and all the different ways we have of dividing it up and talking about it as merely illusions? That’s the most hard-core attitude we could take to reality, sometimes called eliminativism, since its adherents like nothing better than to go around eliminating this or that concept from our list of what is real. For an eliminativist, the question “Which Captian Kirk is the real one?” gets answered by, “Who cares? People are illusions. They’re just fictitious stories we tell about the one true world.”

I’m going to argue for a different view: our fundamental ontology, the best way we have of talking about the world at the deepest level, is extremely sparse. But many concepts that are part of non-fundamental ways we have of talking about the world- useful ideas describing higher-level, macroscopic reality- deserve to be called “real.”

The key word there is “useful.” There are certainly non-useful ways of talking about the world. In scientific contexts, we refer to such non-useful ways as “wrong” or “false.” A way of talking isn’t just a list of concepts; it will generally include a set of rules for using them, and relationships among them. Every scientific theory is a way of talking about the world, according to which we can say things like “There are things called planets, and something called the sun, all of which move through something called space, and planets do something called orbiting the sun, and those orbits describe a particular shape in space called an ellipse.” That’s basically Johannes Kepler’s theory of planetary motion, developed after Copernicus argued for the sun being at the center of the solar system but before Isaac Newton explained it all in terms of the force of gravity. Today, we would say that Kepler’s theory is fairly useful in certain circumstances, but it’s not as useful as Newton’s, which in turn isn’t as broadly useful as Einstein’s general theory of relativity.

…

A poetic naturalist will agree that both Captain Kirk and the Ship of Theseus are simply ways of talking about certain collections of atoms stretching through space and time. The difference is that an eliminativist will say “and therefore they are just illusions,” while the poetic naturalist says “but they are no less real for all of that.”

There are some good things about what Carroll is doing here. He is right of course to insist that the things of common experience are “real.” He is also right to see some relationship between saying that something is real and saying that talking about it is useful, but this is certainly worth additional consideration, and he does not really do it justice.

The problematic part is that, on account of his pre-Socratic tendencies, he is falling somewhat into the error of Parmenides. The error of Parmenides was to suppose that being can be, and can be thought and said, in only one way. Carroll, on account of confusing the various meanings of “fundamental,” supposes that being can be in only one way, namely as something elemental, but that it can be thought and said in many ways.

The problem with this, apart from the falsity of asserting that being can be in only one way, is that no metaphysical account is given whereby it would be reasonable to say that being can be thought and said in many ways, given that it can be in only one way. Carroll is trying to point in that direction by saying that our common speech is useful, so it must be about real things; but the eliminativist would respond, “Useful to whom? The things that you are saying this is useful for are illusions and do not exist. So even your supposed usefulness does not exist.” And Carroll will have no valid response, because he has already admitted to agreeing with the eliminativist on a metaphysical level.

The correct answer to this is the one given by Aristotle. Material causes do not sufficiently explain reality, but other causes are necessary as well. But this means that the eliminativist is mistaken on a metaphysical level, not merely in his way of speaking.

Knowing Knowing is Secondary

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It would be a mistake in general to suppose that one could derive all important truths from a few first principles, but one particular way to fall into this error would be to think that one can or should derive metaphysics or other branches of scientific or philosophical knowledge from epistemology. One reason for this is implied by the previous post: insofar as we come to know knowledge from a knowledge of the known or knowable, it is never possible to begin by thinking about knowledge, but one must begin by thinking about things.

Descartes’s discussion of the scenario of the evil demon appears to be an example of this error, insofar as he seems to suggest that his first knowledge is of the fact that he is thinking something. In fact, it is quite evident that one must know oneself in order to have the thought, “I am thinking,” and that one would never think about thinking without first thinking about something else.

Still, Descartes’s adoption of this error is only partial. He does realize that this is not the natural order of coming to know. Thus in the Synopsis of his Meditations he says:

Finally in the Sixth I distinguish the action of the understanding from that of the imagination; the marks by which this distinction is made are described. I here show that the mind of man is really distinct from the body, and at the same time that the two are so closely joined together that they form, so to speak, a single thing. All the errors which proceed from the senses are then surveyed, while the means of avoiding them are demonstrated, and finally all the reasons from which we may deduce the existence of material things are set forth. Not that I judge them to be very useful in establishing that which they prove, to wit, that there is in truth a world, that men possess bodies, and other such things which never have been doubted by anyone of sense; but because in considering these closely we come to see that they are neither so strong nor so evident as those arguments which lead us to the knowledge of our mind and of God; so that these last must be the most certain and most evident facts which can fall within the cognizance of the human mind. And this is the whole matter that I have tried to prove in these Meditations, for which reason I here omit to speak of many other questions which I dealt incidentally in this discussion.
Descartes cannot be excused from error here insofar as he asserts that “the knowledge of our mind and of God” are “the most certain and most evident facts” that we can know, but he does realize that people do not actually deduce the existence of an external world from the fact that they think. This is why he admits that such things “never have been doubted by anyone of sense.”

Evil Demon

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Descartes begins his Meditations on First Philosophy:

It is now some years since I detected how many were the false beliefs that I had from my earliest youth admitted as true, and how doubtful was everything I had since constructed on this basis; and from that time I was convinced that I must once for all seriously undertake to rid myself of all the opinions which I had formerly accepted, and commence to build anew from the foundation, if I wanted to establish any firm and permanent structure in the sciences.

In order to do this, he says, it is necessary to doubt all of his former opinions. So he invents a hypothesis to render them doubtful:

I shall then suppose, not that God who is supremely good and the fountain of truth, but some evil genius not less powerful than deceitful, has employed his whole energies in deceiving me; I shall consider that the heavens, the earth, colours, figures, sound, and all other external things are nought but the illusions and dreams of which this genius has availed himself in order to lay traps for my credulity; I shall consider myself as having no hands, no eyes, no flesh, no blood, nor any senses, yet falsely believing myself to possess all these things; I shall remain obstinately attached to this idea, and if by this means it is not in my power to arrive at the knowledge of any truth, I may at least do what is in my power [i.e. suspend my judgment], and with firm purpose avoid giving credence to any false thing, or being imposed upon by this arch deceiver, however powerful and deceptive he may be. But this task is a laborious one, and insensibly a certain lassitude leads me into the course of my ordinary life. And just as a captive who in sleep enjoys an imaginary liberty, when he begins to suspect that his liberty is but a dream, fears to awaken, and conspires with these agreeable illusions that the deception may be prolonged, so insensibly of my own accord I fall back into my former opinions, and I dread awakening from this slumber, lest the laborious wakefulness which would follow the tranquility of this repose should have to be spent not in daylight, but in the excessive darkness of the difficulties which have just been discussed.

He continues with his second meditation:

The Meditation of yesterday filled my mind with so many doubts that it is no longer in my power to forget them. And yet I do not see in what manner I can resolve them; and, just as if I had all of a sudden fallen into very deep water, I am so disconcerted that I can neither make certain of setting my feet on the bottom, nor can I swim and so support myself on the surface. I shall nevertheless make an effort and follow anew the same path as that on which I yesterday entered, i.e. I shall proceed by setting aside all that in which the least doubt could be supposed to exist, just as if I had discovered that it was absolutely false; and I shall ever follow in this road until I have met with something which is certain, or at least, if I can do nothing else, until I have learned for certain that there is nothing in the world that is certain. Archimedes, in order that he might draw the terrestrial globe out of its place, and transport it elsewhere, demanded only that one point should be fixed and immoveable; in the same way I shall have the right to conceive high hopes if I am happy enough to discover one thing only which is certain and indubitable. I suppose, then, that all the things that I see are false; I persuade myself that nothing has ever existed of all that my fallacious memory represents to me. I consider that I possess no senses; I imagine that body, figure, extension, movement and place are but the fictions of my mind. What, then, can be esteemed as true? Perhaps nothing at all, unless that there is nothing in the world that is certain. But how can I know there is not something different from those things that I have just considered, of which one cannot have the slightest doubt? Is there not some God, or some other being by whatever name we call it, who puts these reflections into my mind? That is not necessary, for is it not possible that I am capable of producing them myself? I myself, am I not at least something? But I have already denied that I had senses and body. Yet I hesitate, for what follows from that? Am I so dependent on body and senses that I cannot exist without these? But I was persuaded that there was nothing in all the world, that there was no heaven, no earth, that there were no minds, nor any bodies: was I not then likewise persuaded that I did not exist? Not at all; of a surety I myself did exist since I persuaded myself of something [or merely because I thought of something]. But there is some deceiver or other, very powerful and very cunning, who ever employs his ingenuity in deceiving me. Then without doubt I exist also if he deceives me, and let him deceive me as much as he will, he can never cause me to be nothing so long as I think that I am something. So that after having reflected well and carefully examined all things, we must come to the definite conclusion that this proposition: I am, I exist, is necessarily true each time that I pronounce it, or that I mentally conceive it.

Descartes’s demon is not very powerful. Otherwise, why should it not deceive him into believing that it is necessarily true that he must exist in order to think that he exists, even if this is false? In other words, it may be that Descartes can think that he exists even without existing, but the evil demon can deceive him into believing that it is perfectly obvious that this is impossible.

The situation is of course incoherent. But it would also be incoherent for two and two not to make four, and presumably Descartes meant to call this into question as well, or his existence would no longer have the special place of primacy that he is giving it here.

We noted earlier that in order to have a good conversation, we need to concede something to our conversational partner. We can take to this to its ultimate limit by noting that we cannot hold a conversation at all with someone who will not respond except in order to say, “no, that’s wrong.” Suggesting that an evil demon hypothesis (or some equivalent) is true about someone is in effect replying to everything he says in this way. Likewise, suggesting that such a hypothesis might be true about someone, in the sense that there is a substantial doubt about the hypothesis, is in effect responding to everything with, “you might be wrong anyway,” which will be no more effective in producing a conversation.