In a previous essay, I described how radical skepticism could be used to investigate the nature of one's reality. Here I will continue that line of reasoning to support the claim that materialism is a philosophical dead-end, and why idealism should be given more consideration.
First, let us recall the basic argument of radical skepticism. A simplified form goes like this:
Consider the hypothesis that all of reality sprang into being, fully formed, last Thursday—with only the appearance of being billions of years old.
How could you distinguish this hypothesis from the standard (materialist) view?
By its very construction, it is impossible to use any evidence whatsoever to tell it apart from the usual view. You may have a memory of last Wednesday, but perhaps those are false memories that popped into being last Thursday. Same with all your photographs, history books, etc. Even general principles (like Occam's Razor) become unavailable for use, since they could only have been justified in a past that you cannot rely on.
To tighten the noose further, replace "last Thursday" with "yesterday," or better yet, "one moment ago." Can you be sure that you actually read the start of this very piece? You certainly have a strong memory and feeling that you did, but perhaps you and those memories popped into being just a moment ago.
No amount of reasoning or evidence can tell this hypothesis apart from the standard one. Therefore, your belief in either one is completely unjustified. You cannot say that either is "more likely" to be true.
By a similar argument, there is no way to disprove the hypothesis that reality is a simulation, where the simulators are clever enough to hide all evidence of this fact from us. In fact, there are an infinite number of strange possibilities that are impossible to disprove. Upon realizing this, a common response is to say: in that case, I am free to pick whichever possibility is simplest—and materialism is the most straightforward of all. This logic contains a subtle but egregious error. Let us see why.
If materialism is true, then you are a human with limited capacities. In particular, you are limited to using evidence and reasoning to discover truth. But as we have just seen, no amount of evidence and reasoning could ever allow you to disprove the possibility that this is all a dream (for example). Putting these facts together, we see that even if materialism were true, you would have no reason whatsoever to believe that it was true. This makes it a complete dead end. Why waste your time with a belief that you not only have no reason to believe in, but that you could not even come one iota closer to confirming, even if it somehow happened to be true?
The only reason people take it seriously is that they believe that all metaphysics suffer from this same devastating criticism, and so they're all equally valid (or invalid). But while it's true that evidence and reasoning are insufficient to distinguish between metaphysics, concluding that they therefore cannot be distinguished is to presuppose that evidence and reasoning are the only tools available to you. In other words, it presupposes (something like) materialism. The game is rigged. But there's another possibility.
Suppose that what you really are is the very ground of being, having woven itself into a beautiful dream, in which you seem to be a human with limited capacities. While still in human form, you indeed seem to be limited. But in this metaphysics, nothing prevents you from waking up and discovering your true nature.
This is a subtle but crucial point, so let's go over it carefully. If you are the very ground of reality, then there is nothing outside yourself that could fool you. Nonetheless, being infinitely clever and powerful, you might be able to fool yourself (into believing that you're a human navigating a physical reality, for example). But if you decided to stop fooling yourself, then—with nothing inside or outside left to trick you—you could conceivably confirm the truth, in a way that materialism (amongst others) simply cannot be confirmed.
What might such a confirmation be like? Trying to answer this question is fraught. No matter what you imagine, you will be able to convince yourself that this "confirmation" could itself be the product of a very real brain, and therefore just as fallible as any other experience. From there, you might reason that pursuing idealism is also a dead end. This would be a mistake.
It is helpful not to approach this by imagining what such a confirmation might be like. It would not necessarily fit into any category that is conceivable to you now—including the seemingly unconstrained category of "potential experiences that a person can have." Instead, revisit the reasoning given above. If it were true that you are ultimately omniscient (in some suitable sense), then there may exist some condition that would lay this fact bare, in a way that has no analog in other metaphysics. That is all we need for now.
One upshot is this: when one person claims to know that idealism is true, and another that materialism is, only the former could even conceivably be telling the truth. The latter must either be lying or, more commonly, expressing an article of pure faith that they have not yet recognized as such. It is important to understand that this is not polemics: even hardcore materialists freely admit this latter point[1].
Assuming that you see (or sense) the inescapable truth of this, what might you do to "awaken" and confirm it for yourself?
We've already seen that reasoning is of limited help in discovering ultimate truth, and so we'll have to discover an even more fundamental tool.
It seems like you cannot be sure of anything in reality, but there is one thing you can be certain of: it sure seems like something is happening. Go ahead and confirm this for yourself. Do not leave even a shred of uncertainty.
Now, focus on some particular thing that seems to be happening—say, a sound. Normally we take the perspective that "I am conscious of this sound." But here, let us redefine the word "consciousness." Instead of being something you have, conceive of it as the very fabric of which the sound is made. Try to see consciousness as a phenomenon which is expressing itself in the form of sound. Do this with a few different sounds.
Now do the same with the sense of touch. Press a body part against something, and discover the sense in which consciousness is now taking the form of sensations of pressure. One by one, do this for all of your five senses.
If words like "real" and "exists" are to have any meaning at all, it should be crystal clear that this phenomenon we're calling "consciousness" is the one thing you can be certain is real or exists.
Now notice that your thoughts are also made of consciousness. This one is harder to do, because we're normally so thoroughly identified with thought that we can't "see" it as a form of experience like sights and sounds. Nonetheless, give it a try. Perhaps try "speaking" a thought slowly aloud in your mind.
In any moment, there are two orientations you can take. One is to follow the content of your thoughts. We normally call this process "thinking," and it occupies the vast majority of our waking (and dreaming) moments without our noticing. The other is to become aware of the nature or texture or essence of thought; to see it (and everything else) as an evanescent formation of consciousness. We will call these orientations "outward" and "inward," respectively.
What happens when you exclusively face outward? Very quickly, you lose contact with the direct wonderment of being alive. Instead of being something richly experiential, life becomes a conceptual affair. As you get more lost, you become able to doubt the very existence of consciousness—perhaps theorizing that it's the mere byproduct of something you "know" to exist, such as matter. In its more insidious forms, the outward orientation convinces you that reality is mundane; inert; lifeless. Mere stuff pointlessly bouncing around. You begin to see reality as a collection of resources that each being must compete over to maximize their enjoyment during their brief, meaningless stay.
What happens when you turn inward? You begin to recall the sheer magic of being alive. You notice that the very phenomenon you call "being alive" is just another name for consciousness gloriously expressing itself. You are filled with gratitude and awe. You begin to notice the immense love that must have been expressed just to bring your human form to where it is now, and vow to return the favor. You realize that life is deeply sacred, and not to be taken lightly. You reflect on the tragicomedy of humans taking ourselves and our beliefs so seriously. In its more extreme forms, the inward orientation results in the miracle of existence remembering itself through you; a process we call "awakening."
Many great thinkers and sages have noted that our task must be to awaken. While actually doing so requires a deep commitment that goes far beyond the intellectual, it is hard to see how we might accomplish the task without a shared worldview that admits its possibility and significance. Our culture has been so entirely focused on the outward orientation that we've forgotten that another one exists—one that is crucial to our survival. This forgetting has become so thorough that our modern institutions don't even permit honest discussion about perspectives on reality other than materialism—a view that, astonishingly, it has already proven to be fundamentally unjustifiable.
For all its past successes, this perspective is now running into a dead end; an increasingly literal one, at that. It is time for us to take notice and wake up.
[1] (Arch-skeptic) Sean Carroll:
There is no way to distinguish between the scenarios by collecting new data.
What we’re left with is our choice of prior credences. We’re allowed to pick priors however we want—and every possibility should get some nonzero number. But it’s okay to set our prior credence in radically skeptical scenarios at very low values, and attach higher prior credence to the straightforwardly realistic possibilities.
Radical skepticism is less useful to us; it gives us no way to go through life. All of our purported knowledge [...] might very well be tricks being played on us. But what then? We cannot actually act on such a belief [...]. Whereas, if we take the world roughly at face value, we have a way of moving forward. There are things we want to do, questions we want to answer, and strategies for making them happen. We have every right to give high credence to views of the world that are productive and fruitful, in preference to those that would leave us paralyzed with ennui.
This is an important passage. Suppose you have two hypotheses that both fit some evidence. If collecting new data does not help you distinguish the hypotheses, then you are free to pick whichever hypothesis you like. This means that materialism is entirely a matter of preference. Of course, the implication here is that idealism is, too, but as we see in the main text, that would only be true if it were constrained in the same way materialism is—which it is not.