One Possible Case For Illusionism

Broadly construed, illusionism is a thesis about awareness of phenomenal character. It is the claim that any awareness of phenomenal character is non-veridical. On the face of it, illusionism seems patently absurd. If I seem to be aware of a bent stick, it’s certainly possible that no bent stick is actually present. But if I *seem* to be aware of the qualitative features presented by my experience, it appears that this is totally sufficient for *actually* being aware of such features. When it comes to phenomenal character, it is hard to deny that appearance simply is reality. 

Why do we think that phenomenal character is unique in this way? One plausible answer is that, in experience, the essence of phenomenal character is completely revealed to us. When I am aware of some phenomenal character, this is enough for me to completely grasp the nature of that phenomenal character. Consequently, I cannot be mistaken about what I am aware of because I have complete knowledge of what it is to be that phenomenal character. Since I have this knowledge, I know that being aware of something like *that* (where ‘that’ refers to what I am aware of), is the same as being aware of the relevant phenomenal character. 

If experience does, in fact, reveal the essence of phenomenal character to us in this way, how could illusionism possibly be true? One possibility is that, although experience completely reveals the nature of phenomenal character to us, the relevant phenomenal character is never actually instantiated. In other words, when we are aware of a certain phenomenal character, this does not entail the instantiation of any phenomenal character that we are aware of.

This might sound strange at first, but it is very similar to a phenomenon that we are all familiar with: Suppose that someone is thinking about a unicorn. Even though, in such a case, it is true that someone is thinking about a unicorn, this does not entail that there is any unicorn that someone is thinking about. If it did, we could simply infer that unicorns exist from the fact that people can think about them. But this inference is blocked in such a context. The cases in which this sort of inference is blocked are known as “intensional contexts”. Thinking is such a context and it is open to the illusionist to claim that awareness is such a context as well. If this were the case, the fact that someone is aware of a certain phenomenal character is not, on its own, sufficient to conclude that any phenomenal character is actually present. If one is aware of some phenomenal character that is not actually instantiated, such awareness is non-veridical. In this sense, such awareness is illusory. 

So, perhaps realists about phenomenal character are correct about revelation. In experience, the nature of phenomenal character is wholly revealed to us. But the illusionist might nevertheless hold that they are wrong insofar as they hold that phenomenal character is actually instantiated in the world. But why would anyone think this? On the face of it, experience seems to at least provide defeasible evidence for believing that phenomenal character is present just like it does for anything else we seem to be aware of. If we think that phenomenal character is illusory, why not think that the ordinary objects of our environment are illusory as well? Why not think that everything we seem to experience is an illusion? The illusionist owes us some reason for thinking that phenomenal character is illusory that does not also apply to everything else that we perceive. Otherwise, they undermine the very sorts of scientific evidence that led them to propose illusionism in the first place.

One reason of this sort that the illusionist can give takes the form of a debunking argument against our knowledge of phenomenal character. Specifically, they can argue that our beliefs about the presence of phenomenal character are “accidental” in a problematic sense that is incompatible with such beliefs counting as knowledge. 

In what sense might our beliefs about phenomenal character be accidental? In order to count as knowledge, one plausible requirement is that the things that our beliefs are about must play some role in explaining why we form reliably true beliefs about them. For instance, suppose someone takes a pill that causes them to develop a completely random disposition to form beliefs about when it is going to rain. Suppose that, as a matter of sheer coincidence, they happen to form a disposition to believe it is going to rain when it is dark and cloudy, the weatherman says it’s going to rain, etc. In such a case, the person would have reliably true beliefs about rain that were formed on the basis of good reasons for thinking it is going to going to rain. Nevertheless, because their disposition was a completely random result of the pill that they took, it is accidental. Consequently, it reasonable to suppose that their beliefs still fail to count as knowledge.

If this sort of “non-accidental” constraint is accepted, it can also be applied in the case of phenomenal character. Suppose it is granted that, when we have phenomenally conscious experiences, we reliably form true beliefs that are caused by the appropriate sorts of phenomenally conscious experiences. Nevertheless, the illusionist might claim that the reason we form reliably true beliefs on the basis of those experiences has nothing to do with the phenomenal character that those experiences actually have. For example, according to many panpsychists, the same causal-structural properties described by physics could be realized by quiddities that lacked phenomenal consciousness. In this sense, although phenomenally conscious experiences do, in fact, cause us to form true beliefs about them, their phenomenal character plays no role in an explanation of why we form the beliefs that we do. That sort of explanation might only appeal to the causal-structural features that are only contingently associated with the quiddities responsible for phenomenal consciousness. If this is so, our beliefs about phenomenal character might be accidental and, thus, fail to count as knowledge *even if* they are actually caused by phenomenally conscious experiences. 

By appealing to the requirement that our doxastic dispositions must be non-accidental, illusionists can argue that our beliefs about phenomenal character do not count as knowledge without ruling out our knowledge of other objects and properties in our environment. On this basis, they can defend a form of physicalism that does not countenance phenomenal character and hold that experiences of such properties are non-veridical. Furthermore, they can also explain our apparent certainty that such properties are instantiated by appealing to the revelatory character of our experiences. Since experience might reveal the essence of phenomenal character without phenomenal character actually being instantiated, revelation alone cannot undermine illusionism. 

The above considerations strike me as a plausible line that illusionists might take in response to realism about phenomenal character. While I do not personally accept the illusionist thesis, it does strike me as being more plausible than any realist proposal that demands a radical transformation of physics in light of phenomenal consciousness.

Names And Propositions

A proposition can occur in discourse with or without being asserted (Geach, “Assertion”). For example, if I assert “If P then Q”, Q occurs without being asserted (though, of course, I certainly could assert it). However, we have to distinguish between two sets of cases. First, there are cases where a proposition occurs in an assertion without itself being asserted. Second, there are cases where it appears as though a proposition occurs without being asserted when, in fact, what occurs is merely a name. 

The first sorts of cases occur when logical operations are applied to form new propositions such as “P v ~P” or “If P, Then Q”. These propositions do not add any descriptive content over and above what is described by the simple, unasserted propositions that they contain. Instead, they simply depend for their truth/falsehood upon the logical relations that hold between the states of affairs that the simple propositions describe. 

The second sorts of cases occur when a simple proposition seems to occur unasserted within a proposition that, unlike propositions of the first sort, *does* describe some further bit of reality. For example, “Q” seems to occur within “A believes that Q” even though the latter proposition apparently describes a further relation between “Q” and a subject. However, despite appearances, I think these can only be understood as cases where “Q” is a name that refers to some proposition that, correctly or incorrectly, describes reality. Among other things, this is why “A believes ‘Hesperus is a star’” does not entail “A believes ‘Phosphorus is a star’”. It also explains why “A believes ‘Unicorns have four legs’” does not entail “Unicorns have four legs” (since the former proposition does not describe a relation between A and whatever some proposition describes). 

If the above claims are true, a problem arises for inferences of the following form:

1. John believes that ‘P’

2. P

3. John believes truly that ‘P’ (or “John’s thought is true” or “‘P’ is true”, etc.) 

As discussed previously, ‘P’ occurs in the first premise as a name. Furthermore, John’s belief is true iff the proposition the ‘P’ names is true.  It may seem that this is precisely what the second premise affirms. However, despite appearances, the first and second premises have nothing in common with one another. In the first premise, ‘P’ is a name. In the second, “P” is a proposition (affirming the name ‘P’ makes no more sense than affirming the name ‘John’). Affirming “P” does not license us to infer that ‘P’ is true any more than it licenses us to infer that some arbitrary proposition named ‘A’ is true. As a matter of fact, ‘P’ names the very proposition that we affirm, so the conclusion is true, but there’s no logical reason why ‘P’ could not name a completely different proposition. As a matter of logical inference, concluding that John’s belief is true is totally unjustified. 

In order to avoid this problem, one might hold that genuine propositions can occur in intensional contexts without being asserted. However, one must then explain why such propositions have their unusual features that differ from those that result from ordinary logical operations. Alternatively, one might reject inferences of the sort presented above and explain their apparent legitimacy on other grounds. Finally, one might deny that intensional propositions describe relations between subjects and propositions at all. In this case, one must give an alternative account of what this form of discourse amounts to and why the relevant inferences are justified. In my opinion, this final option holds the most promise.

“That the propositional sign is a fact is concealed by the ordinary form of expression, written or printed. (For in the printed proposition, for example, the sign of a proposition does not appear essentially different from a word. Thus it was possible for Frege to call the proposition a compounded name.)” - Ludwig Wittgenstein

From Physicalism To Mysterianism

 In a previous post on this blog, I defended a broadly physicalist approach to the mind-body problem. Arguments from causal closure and scientific explanation led me to the think that the mind, like many other aspects of our “manifest image”, should be identified with physical phenomena on a posteriori grounds. 

Recently, I’ve come to think that this view is mistaken for an unexpected reason: It seems to me that we are not in a position to make any confident claims about whether the mind is or is not physical. To the extent that the question of mind-body identity can be meaningfully posed at all, I now lean towards a form of mysterianism. Here is a brief outline of my reasons:

A compelling way to frame the mind body problem is in terms of what has been called the “explanatory gap”. This highlights the intuitive sense in which, even if all the physical facts are explained, we’ll still be no closer to understanding how the physical “stuff” yields our technicolor phenomenal experiences. Why are those brain states like *this*!? Someone might ask. 

In one sense, the explanatory gap may seem to depend upon a confusion. Namely, identities aren’t really the sorts of things that can be explained at all. There’s no explanation for why I’m me or why Clark Kent is Superman. In each case, it’s the same person. If explanations ever come to an end, surely it must be with identity. Likewise, if we have good reasons for thinking that the mind is identical with the brain, we don’t require any further explanation for why they are, in fact identical. 

But the anti-physicalist has a more pressing version of this problem available to them: In normal cases of scientific identification, it seems possible to deduce all higher-order physical truths from the actual set of microphysical truths. To use a simple example, if I know all the facts about H20, it seems clear that I will be in a position to deduce all the facts about water on the basis of those truths. We know that water is whatever liquidy stuff plays the “water” role in our environment, so once we know that that role is filled by H20, we’ll know everything we need to know about water, right? If that’s the case, it seems like the obvious impossibility of deducing such truths about consciousness is good evidence against physicalism.

One of the most popular (and plausible, in my opinion) physicalist replies to this claim comes from what has been called “a posteriori physicalism”. According to a posteriori physicalism, microphysical truths alone do not put us in a position to deduce higher-order physical truths, even in humdrum cases such as water and H20. The key mistake that they point out is the assumption that we know, a priori, that water is the liquidy stuff that plays the water role in our environment. While this might seem completely obvious, keep in mind that what matters is whether that claim is a priori, not whether it is obvious. 

Upon reflection, we can easily imagine cases in which that obvious fact turns out to be false. For instance, we could discover that water isn’t actually liquid at all and that we are being deceived by technologically advanced aliens about its nature. In such a case, knowing that H20 is a liquidy stuff wouldn’t be enough to know anything about water because water isn’t a liquidy stuff at all! We discovered, a posteriori, that it was very different than what we initially supposed. As far fetched as this may seem, this case and many others like it cannot be ruled out on a priori grounds. Consequently, we cannot deduce all physical truths, a priori, from microphysical truths alone.

However, while this reply may succeed as a reply to the a priori physicalist, it fails to address what I’ve come to think is a much deeper divide between the mind and other physical phenomena.

Consider any physical phenomena of the everyday world. Water, heat, plants, and anything else that science appears to explain. In normal cases, when we identify something like water with an empirical concept from a more developed theory such as H20, we are effectively concluding that truths about one of the identified terms (water) are systematically correlated with truths about the other term (Complex structures of H20 molecules). Even if we don’t make the exact same judgements about each, what matters is that judgements about one can be, in principle, replaced by judgements about the other (or some disjunctive set of such judgements). 

It doesn’t matter if we never reach a level of sophistication where this is actually possible. What matters is that, in ordinary cases, a necessary condition for a posteriori identity is the *in principle* dispensability of the higher-order theoretical vocabulary. In other words, it must be possible to replace our talk about water with talk about H20 without missing out on any significant truths about reality (excluding, of course, trivial cases such as the fact that we use the term “water”). Just like we can capture all the truths about the world by talking about Clark Kent alone, rather than Clark Kent and Superman, we should be able to talk about H20 instead of water and still say everything we said before. If they’re really the same thing, this much seems to me to be obvious. 

In light of the above considerations, we now have a new necessary conditions for a posteriori identification that can replace that of the a priori physicalist: If some empirical phenomenon X is identical with some empirical phenomenon Y, the vocabulary associated with “X” must be, in principle, capable of being replaced by the vocabulary associated with “Y” without any loss of expressive power with respect to the coarse grained empirical facts those terms were used to describe. (For a more sophisticated development of ideas along these lines, see Sellars 1965)

Now, if this condition is necessary for a posteriori identification, how does the mind fare? With respect to phenomenal consciousness, there is one simple reason why I believe this condition can never be satisfied: Unlike our ordinary empirical concepts, our sensory experiences do not merely serve to describe reality. They also play an essential epistemic role in justifying our empirical beliefs. Even if I am mistaken about what I perceive, I am always in a privileged epistemic position with respect to what seems to be the case. It is because we have such experiences that we can be in a position to form judgements about the world at all. Most importantly, such experiences put us in a position to form judgements about the brain. 

Because our judgements about the brain depend upon the epistemic function of our sensory experiences, we can never be in a position to replace judgements about phenomenal consciousness with judgements about brain states. Why not? Because judgements about brain states are empirical judgements. As such, they require us to recognize what we experience as what we experience in order for us to have justified beliefs about them at all. If we abandoned the vocabulary of conscious experience, we would undermine the very basis for identifying the mind with the brain in the first place. Since abandoning our mental vocabulary is self-refuting, we cannot be in a position to identify the mind with the brain. 

Does this conclusion entail anti-physicalism? Not quite. Recall the reason why the mind cannot be identified with the brain. It had nothing to do with the metaphysical nature of consciousness. Rather, the impossibility derived from the epistemic role that consciousness plays. This epistemic role, however, carries no implications for what the nature of consciousness actually is. On the contrary, because it plays an essential epistemic role for our empirical knowledge, our inability to identify consciousness with anything physical derives from factors that have nothing to do with what consciousness actually is. Whether consciousness is physical or non-physical, we are not in a position to identify it as such. And since this inability does not stem from the metaphysical nature of consciousness, it does not allow us to draw any metaphysical conclusions about consciousness for or against physicalism. In short, the epistemic role played by sensory consciousness prevents us from being in a position to reach any firm conclusion about whether it is a physical phenomenon. 

Taken alone, this thesis yields a novel form of mysterianism that appeals to the epistemic features of consciousness, rather than the conceptual limitations of our current scientific framework. I believe there is a further question to ask about whether this leaves any meaningful way to formulate the mind body problem at all, but for now I’ll end at that.