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.