Is R real?

[Speakpigeon]

It just happens that for a very long time we believed we knew the physical world. It's only recently, with science, that we have now more reasons to believe we now nothing about it.

Such as?

For example that we believe we are entirely biological organisms and that we can only interact with our environment through a perception system whose processes are entirely unconscious and therefore unknown to us except for the final representations we get within our mind of this environment. We know the representations, not what is represented. That's a fundamental fact about us. And whatever science we can do about our perception system cannot change this fact.
EB

Are you seriously under the impression that giving examples of things we can't know about the physical world qualifies as evidence we know nothing about it? That's illogical. You might as well try to prove man can never fly, because he has no wings, and try to prove it by presenting a list of wingless animals that can't fly.

This is getting painful to watch...

My example wasn't an example of "things we can't know about the physical world". It was an example of the evidence we have that we don't know things. It's an example of a good reason to believe we don't know and we can't know the physical world.

No, it's an example of a good reason to believe we don't know and we can't know some things about the physical world. Whether the representations our perception system builds for us are correct representations of what is represented is unknown to us, yes. But whether those perceptions are correct is just an example; it's not the sum total of what is available to be known about the world. There are other things available that your argument doesn't touch.

It didn't touch them because that's irrelevant. As we believe our situation is, all we could possibly know about anything about the world has to go through our perception system. So, yes, we believe that the sum total of what we could possibly know depends on our biological organism, something we don't control.

How the heck do you figure that the fundamental fact about us that we are entirely biological organisms and that we can only interact with our environment through a perception system whose processes are entirely unconscious qualifies as a reason that we can't know, for example, that the physical world contains processes that are unconscious to us? We don't need to know what's on the other end of our perception processes to know that much.

Any idiot can understand he doesn't know anything about the world as soon as he can figure out any possibility that he be wrong about everything he believes about the world. Descartes already explained how it goes. And so of course, once you admit you don't know, you also admit the obvious that you don't know you even have perception organs to begin with. It's a logical argument. A simple reductio ad absurdum. I'm sure you could try it.

Or consider the example I gave you earlier. The physical world contains simulations. By systematic doubt, how do you figure we could be wrong about that? Either it contains the simulations we think we see from our perception system, or else the world is somehow simulating them.

Sorry, I don't understand your point here. You seem to start by assuming something we don't know, that there is a physical world. And how do we get to think we see "simulations"?!
EB

 

[Speakpigeon]

Consider the alternate world of Conway's Life. There's no matter or energy in that world, just bits. It's a world of pure information. Do you think if conscious beings evolved there, they wouldn't be able to do research, invent a science of physics, and discover the laws of their universe, because there are no material things or energy there for them to discover?

Oh sure, I mean "possibly", but they would have their own dictionary where "physical world" would mean something else than it does to us.

If you want to call "physical world" anything that exists that's not my mind, then, supposing God exist, and only God beside our minds, we would have to see God as the physical world?! That's just playing fast and loose with words.

We are discussing the physical world of our reality here and now. Not the abstract concept of "physical world" that you seem to think is a good generalisation of what people ordinarily think of as their physical world.

The reason people think physics isn't the study of minds is because we live in a world where mind is not fundamental. It's an emergent property of matter, here. But in the alternate possible worlds you postulated, mind is fundamental. In that world, what argument would there be for physics to be anything other than the study of mind?

Sorry, I didn't postulate any alternate world.

You might as well claim that "water" means "H₂O", and therefore infer that if Cavendish had found out the stuff contained sodium instead of hydrogen then that would have meant we'd been wrong all along about whether the sea is full of water.

Anybody learning that his mind is all that exists wouldn't go on to reflect that his mind was the physical world after all. He would just think, well, the physical world just doesn't exist.
EB

How could anyone conceivably learn that his mind is all that exists? A person reaching that conclusion would simply be choosing to rename the parts of reality he doesn't have conscious access to "me" instead of "other". That's not learning. That's labeling.

Sorry, I'm not saying we should believe our mind is all that exists.

Sorry, but overall it's a lot of time for little progress. You don't seem to understand my arguments and your arguments are invariably beside the point so I can't see how we could reach an understanding. You seem to think I'm some sort of solipsist. I'm not and you have absolutely no good cause to have assumed such. So, I guess, something's very wrong, somewhere. That, I'm sure, you will agree on.
EB
EB