It seems like despair over the emptiness of existence is something like an occupational hazard for philosophers. Maybe it only seem this way because society especially pushes this image -- or it may be that it primarily affects amateur philosophers who know only enough to be dangerous. Whatever the case, we can at least say that some large number of people who make a habit of analyzing their relation to the universe end up dissatisfied with the results. Probably the only substantial error here is to waste the time analyzing something essentially irrelevant and unanalyzable; but since poorly directed analysis is an entrenched habit of mine, I have a cause to propose for this unfortunate conclusion.
We understand things by analogy, or in other words, "in terms of what we already know." When we attempt to understand the universe itself in terms of things more familiar, we expose the severe limitations of our capacity to understand, to an extent that's almost embarrassing. It's true we can do pretty well predicting some of its behaviors, if we radically isolate the attribute in question and delegate some of the processing to adjunct calculation machinery -- but to me this cannot be called understanding. Understanding is a more rich experience that occurs only with sufficiently complex subject matter which we're able to interact with from many angles.
We create specialized frameworks for anticipating some facet or another of the universe, and we can gain an understanding of several of these with time -- but the degree of their specialization prevents any holistic comprehension. Imagine you must try to understand humans without prior knowledge, but the only route available is to study endocrinology, followed by neurophysiology, followed by rheumatology, etc. When you complete these studies, you will have very good understanding of humans for many definitions of "understanding" -- but as a human, you will find the result dissatisfying, probably because we have divergent modes of understanding which work well only for their respectively appropriate subject matter.
When we ask questions like, "what is the nature of reality?" or "what is the essential character of the universe?" -- questions outside the domain of science -- and seek answers by improving our understanding through the scientific/analytical mode, we have chosen a route than can end only in dissatisfaction. What was confusing to me, though, was which domain these questions are in if not the scientific. What valid modes of understanding could possibly exist besides those grounded in observation and logic? It sounds like since I'm being asked to not use scientific understanding, that I should not observe the phenomena in question, and use some transformations other than logic to elaborate the dubious unobserved starting point of my speculations. This is overreacting.
Why do we ask the question, "what is the nature of reality?" ? One reason is that we are following a chain of causes to some root, because that's what we do. But I think another important and mostly overlooked reason is that it's something we have to co-exist with, and decisions about whether or not to live in the company of some thing are among the most important to humans. So, I propose that "what is the nature of reality?" is really a social question. We want to know whether we can trust the universe, whether he tells good jokes or is always getting into trouble, etc. Our brains are trying to figure out whether a relationship with the universe is the best decision for spreading our genes.
Clearly there's something funny about this question. It gets back to what I was saying about our embarrassingly limited capacity for understanding the universe: our brains try relating it to something already understood and the nearest match is a ways off.
And, when the depressed philosopher reaches the conclusion that reality is fake or empty, what is he getting at? To me, this sounds like a social imputation; that the universe promised to be one thing at some earlier point, but time bore out that it was all pretense. Of course the universe makes no promises, so that she is flaky cannot be a very meaningful claim -- but we did get the idea from somewhere.
When we are young, we just do things, and it's fun. When we get older, and develop our tendencies to abstraction, we want to name things -- especially if we're into creating functional symbolic systems that can compute predictions for us, if only we can find the right set of names for things. To be more precise, we come up with layers of definitions for things, and at the bottom of these definition strata, lie indefinables. Also, it's not always clear to us that these systems are separate from their referents; that a rock flying through the air and F=MA are two different things. So, when we were young, the universe was just mystery -- filled with potential; by the time we lay the groundwork for a more sophisticated comprehension of the universe, we find that it is a series of representations, resting on top of indefinables (i.e. something about which there is nothing whatsoever interesting to say), and no substance. Substance does not exist, only representation. The universe is a charlatan.
First off there is an error here in that it sounds like we've discovered some metaphysical property of the universe -- unfortunately an overly ambitious hope: instead the discovery is epistemological. We don't experience substance directly; our minds operate through representations. This seems to merely transfer the source of the problem, leaving its effects in place. The error here, however, is to think that this is a problem in the first place, that we understand anything about what it means to experience a reality through representation versus directly, or if such a notion is anything but nonsense. The problem is something like trying to imagine the edge of the universe or time travel. Our brains construct a model of the situation when we query them to, but we know better than to trust the model for much more than amusement.
Again, the solution probably is to admit defeat and go play outside.