Jan Ardena:
Because ''weather'' exists, and there is a location known as outside, depending on your location. So when you ask the question, others can formulate a meaning.
You mean you believe there is an outside with weather and so on.
Where is this brain in the vat?
That's right, it is a mental image.
If you are a brain in a vat, you have no way of accessing the information as to where that brain is, physically.
How do you know you did?
If you could be a brain in a vat, non of this may be real.
Just by accepting you could be a BIV means you give up all rights to knowledge of anything.
In the wider reality that Sarkus speaks of, yes. In the local reality of vat-world, no.
You can't really know what is reality if you are a brain in a vat. That means if you think it is possible that you are, then it is possible that I didn't write it, or that I even exist.
Those must also be possibilities.
Look! You said it yourself:
You can't really know what is reality if you are a brain in a vat.
But you claim to know what is reality. You're arguing against yourself, unless you can
prove that you're not a brain in a vat. Which you can't.
I asked you. You're the one claiming we don't know if we're brains in vats.
Ok. Let's take a quick look.
Can a brain entertain anything?
Yes. For example, if you are a brain in a vat, you are,
right now, entertaining the idea that we're having a discussion about brains in vats.
Is it a brain that came up with the notion, or is it a person?
I can't answer this unless you can explain to me what you see as the difference between a brain and a person.
Is it your brain that is discussing, or is it you?
If you're a brain in vat, the brain
is you.
I suggest we look into the capability of brains.
What capacities, specifically, do you think are relevant here?
Jan Ardena said:
If we claim to know something, we have a starting position. Right?
No. Knowing something is a conclusion, not a starting position. We start
not knowing things.
You claim that I wrote something which you replied to. What position did you claim that from? The possibility of being a brain in a vat, or the reality of being a human being? It cannot be both.
If you are a brain in a vat, then it came from the reality of your being a brain in a vat.
If you are not a brain in vat, then it came from that reality.
Not for me. It's a really simple observation.
Do we possess our arms and legs, or are we our are arms and legs??
You avoided answering the question I asked you.
Personally, I think of "my arm" as "mine" because it is attached to "my body". "My body" is mine because I appear to be able to control it, I appear to have sensory impressions from it and so on. As far as I am aware, you cannot control
my arm or feel the touch that my arm feels.
I believe that my arm is controlled by my brain. However, this is a theoretical kind of knowledge, since I do not directly perceive my brain in any way. The "real" control of my arm could conceivably come from elsewhere (like a brain in a vat, for example).
As for "me" as the being who has the thoughts and desires and stuff, I believe that "me" is a construct of my brain. However, as I said, I have no way of knowing where that "me" is physically located, just as I have no way of knowing where my brain is physically located.
As far as I can tell, you have no better claim to knowledge about yourself than I have about myself.
Says Professor Science.
Explain how that could possibly be.
I already did. The details aren't important to the current discussion.
It says that you cannot make any truth, or knowledge claims, because it is possible that you could be a brain in a box. Funnily enough you do make truth and knowledge claims, so you are not a BIaV.
Steeeerrrike!
Sorry, but you're still not getting it, so that shout of triump is a premature celebration for you.
You lost track of the idea of a local reality vs the wider reality again (or never grasped the concept in the first place).
You can make knowledge claims that appear to you to be perfectly consistent with everything you perceive in the local reality. But you have zero basis on which to make knowledge claims about the wider reality.
Your mistake all along has been to assume that your local reality is all that can ever be.
For somebody who believes in God and other supernatural things, your resistance here to the idea that there might be more to the world than you can perceive seems inconsistent. Then again, you always sound like you think you have it all worked out, so may it is consistent with your world view after all.
I can make sense of the world.
If you think it is possible you could be a brain in a vat, you can't.
Why not?