Gopal, If I remember correctly, you define appearance as that which does not exist in its own right, or in itself. That which has no independent existence.
So, the question is, if both reefs and rock appear to you, what is the distinction. How can you be certain rock does not fit that criteria but be uncertain whether reefs does or not. Both are subject to same process of perception, no?
So I feel like I must be missing something in your reasoning. Please explain.
Let me try (not to speak for Gopal). This is probably more of
an analogy (that's important, for Gopal, see it?). Take your body (or your own consciousness). ~You~ kind of exist inside the black box of your brain-mind-body. It's dark in your brain, no light. The world touches your senses, let's take the eyes, but it works the same for all 5. Photons hit your eyes, some hit the rods, some hit the cones, rods gives you black and white, cones gives you color, red, green and blue (only those colors). Then, this information travels down the nerves to the brain. The light stops at the eyes, it then becomes coded traveling the nerves. When it gets to the brain the info is passed around to about 6 or 7 vision centers, different areas of the brain. These different areas interpret different parts of the info, different patterns. One area deciphers vertical and horizontal. Then, the info is compared to already-existing data in the brain. Say the brain has already experienced an elephant. The brain is basically a prediction machine. So the brain takes the sensory data, it's processing the info. At some point it says, yea, that's an elephant you're seeing, and combines its existing elephant-patterns with the incoming data, and you see an elephant. All this happens in a fraction of a second. I've studied perception extensively, this is essentially how it works.
There are sensory neurons which carry data from the outside world to the brain. There are motor neurons going out from the brain to the muscles telling them what to do. But there are no nerves going back to the outside world. So, everything you are seeing, right now, it occurring inside your own brain. You are not seeing the outside world, you are seeing your brains representation of the outside world. Now, I saw all of that at age 18, I traced it all out just like that, on my own, I later read it and confirmed in from books on perception. (Philosophy 101 got me going there, Hume, Locke, but especially Bishop Berkeley).
Bertrand Russell gives a good account of this in one of his books. Later, I had a class, Descartes to Kant. We spent about 3 weeks on Descartes, we spent one day on Kant, and it was a lunch-party-seminar at the professors apartment. Kant is really hard, but he knew all this also.
Now back to Gopal. Now, I had to say
analogy, as Gopal says the outer world does not exist. But all this works the very same for the
consciousness of Gopal. Gopal (says he) can know only his own consciousness. So you see it's all quite simple. Descartes goes into a long scenario how there can be an evil demon which is feeding false data to your senses, and so you are not seeing what's-out-there, you are seeing only the info the demon is feeing you. This is why Gopal says: I can't know. He can only know his own consciousness, and it could be deceived, could be a real person there, it could be merely a false-data-feed, it could only be an appearance (a false data feed).
Now, does all this sound familiar? Yep, seems the Wachowski brothers were very good philosophers, all this is a basis for the film The Matrix (and 3 sequels).
Gopal is absolutely refutable, believe me, I've tried.
All this is why I say the world is a hall of mirrors (I didn't originate that). Our own ~psychology~ is even more devious. Our own psychology performs the same operation in relation to experiencing other people, and understanding other people and events. We see other people and events according to how-we-are, we don't see objectively. So we are always *projecting*, ourselves, out on-to other people and events. So what we see is merely a reflection of who-we-are. Thus, the world is a hall of mirrors, it reflects back to us, what-we-are-inside. That's why everybody has their own opinion, or even their own data, we *~twist~* everything that enters our consciousness (enters the brain, then, the result enters-forms our consciousness). This is VERY difficult to
see, it is
exceptionally difficult to be objective. Because everything validates our own view of the world,
because the only thing we see is our own view. It's exceptionally difficult to get outside of our own view. You'll read all this,
according to your own view, and immediately call it bs. See how that works? It's almost foolproof. Almost, but there is a way out. So, it's almost nonsense to say what ~operates~ in-us, is the Whole. Yes, it's the Whole, but it all passes through our own body-brain-mind-consciousness, our own psychology. This is
crystal clear to me, how human consciousness operates, how it operates in-relation to what's-out-there.