Introspection should not be trusted

A case study in failures of judgment on the deepest, most subjective level

By Yervant Kulbashian. You can support me on Patreon here.

Everybody at some point or other has entertained the following brain-teaser:

Is my experience of red the same as other people’s? What if how I experience red is how you experience blue?

The popularity of this phenomenological musing is based partly on the fact that it has no easy answer, and partly since everyone feels confident they know at least half the answer through direct introspective experience. You are sure you know what red and blue feel like to you, and you might guess that other people have similar experiences, but you can’t prove or disprove the latter.

What this question fails to notice is the dubiousness of one of its core pillars: that you know what the experience of red and blue are like for you. To doubt this seems impossible, and all discussion about subjectivity begins with the assumption that this is ground truth. In the debate on consciousness between Chalmers and Dennett, neither party questioned this fundamental premise — they merely interpreted the events surrounding one’s experience of colour in different ways¹. People even feel slightly offended if you question their ability to “know” their own subjective experiences. Introspection is sacrosanct. And in the end, how could anyone disprove you?

Let’s take another look at that assumption, and by digging into it we’ll see that it cannot be the case, on any level.

To begin with, whenever you say that you know what the experience of red is like (its “quale”; plural “qualia”) you are also saying that it is consistent across time. Otherwise how would you assert that your experience of red could be like my experience of blue? What would you be comparing against what? So the first question really should be:

How sure are you that your experience of red is consistent over time?

Of course, no one else can tell you that this is the case; you must make this judgment for yourself through introspection. And the only way to do that is to somehow compare two experiences of red at two different times, and find that they match, or don’t.

This presents a problem. You can’t actually compare an experience of red in the past to one in the present, for the simple reason that you can’t experience something in the past, now. For objective physical events it is possible to create a recording of an event in the past and compare it with recordings at other times. But this can’t be done for subjective experiences of colours. The only recording you have is your memory. So the only way to compare your experience of red in the past with one in the present is to recall the former memory in your mind, and compare it to your current experience. It is not the content of the memory, however, but the experience of its content that you are hoping to recall. That means you are comparing your present experience of a recollection to another experience, which is also in the present.

This makes it impossible to compare two subjective experiences at two different times. It is therefore also logically impossible to know if your experience of red is consistent across time. The experience could be changing every second, and you would never know. We may even cast doubt on whether red has what you might call a subjective experience; it seems unlikely if every judgment about it is so questionable. Either way, it doesn’t make sense to ask if your experience of red is the same as or different from mine, since the question contains an unjustifiable premise. Perhaps they are the same in this second, and not the same later on.

Although you might be able to understand this argument intellectually, it is unlikely it will convince you to change your judgment about the constancy of your subjective experiences. The illusion is still too strong, and the intuition too powerfully embedded in how your mind forms beliefs. This should remind you that even during introspection your mind can be tricked, since it is subject to the same machinery of transcendental judgments as all the rest of our contemplations.

The mind is by default “credulous”. We have little innate motivation to mistrust or doubt any of our existing beliefs — the effort to do so consistently, at all times, would be too great. So you will tend to continue comfortably with a belief unless there is a compelling reason to raise questions about it, such as when you receive pushback from other people or encounter an inconsistency. The more diligent of us will gradually internalise pieces of criticism and pushback and generate them on our own, as a precautionary measure during contemplation; but we would still only do this on an “as needed” basis.

What happens, then, when no one can give you objective feedback about a belief? As we saw, it is by definition impossible for someone to directly question or doubt conclusions you reach through subjective introspection. Your peers may introduce sceptical doubts about how your experiences relate to our shared world — for example, by showing that one of them was based on an optical illusion or faulty memory — but they cannot provide an outside perspective about the immediate experience itself. Who could tell you that your subjective experience isn’t what you think it is?

This leads to a situation where people simply do not, or cannot doubt their subjectivity. They hold it sacrosanct. David Chalmers made this the cornerstone of his argument about the unique nature of consciousness, arguing that subjective consciousness is in a special category of unquestionable entities. And since no one can (usually) provide a counterargument about your subjective judgments, it becomes nearly impossible to disprove his claims.

The goal of this post was to show how introspection can in fact be subject to the same criticisms as empirical experiences of the world. All contemplation and belief formation are based in, and on, the same machinery of thought and judgment, regardless of the source or subject matter. That the above logical contradiction was not immediately apparent to most people — even to Dennett, who was looking for it — and that it is difficult to absorb the argument even after you hear it, demonstrates that the mind cannot be unmoored from its transcendental foundations. Even at the deepest level, and regardless of how sceptical you claim to be, you will continue to believe as the structure of your mind forces you to believe — it is inescapable².

¹ From Dennett:

You are not authoritative about what is happening in you, but only about what seems to be happening in you — Consciousness Explained

The argument of this post is that even the latter is highly suspect. In fairness, Dennett came pretty close to realising this point in other ways.

² The articles throughout the rest of this website provide a path around this difficulty. They present an alternate mode or model of cognitive psychology that incorporates this inherent difficulty, and prevents it from becoming a problem.