[b]I read recently about how Russell and Wittgenstein would debate in Russell’s’ office over whether one could prove that there was or was not a Rhinoceros in the office.
I got thinking on another thread about being able to prove there is objective reality at all.
I have always assumed we can prove it, but I’m wanting to now press in and really convince myself and question my assumptions.
Please post anything you like with regards to proving there is an objective reality out there.[/b]
One cannot prove the existence of the thing in itself, the reality out there. But for that matter one cannot prove the existence of the mind, the reality in here (taps forehead). Without that distinction, sometimes conceived of as an opposition, I’d ask if there’s any genuine philosophical question at all.
That’s Wittgenstein’s answer. To which Russell says ‘But there’s no rhino in the room’.
And so on, through again, from the top. And then again.
The answer depends on how much you trust your instrumentation.
I can say that I am quite certain, based on the equipment I have available, that there isn’t a rhino in the room with me. However, that could be an artifact of my equipment.
Personally, I think that trusting our equipment makes more sense than not, since has been fine-tuned to allow us to survive. If we need to know if there is a rhino in the room, we will. Otherwise: who cares?
Or the equipment may be haunted. And the equipment you use to test whether the first equipment is haunted may be haunted. And so on.
That is, it has been fine-tuned, if the evidence we’ve received via it is to be taken as valid, hence this argument is circular.
Bin Laden? Undetectable rhinos would be an awesome terrorist weapon. 9/11 meets Jumanji. Sorta. 
My answer might be a word-trick, tell me if I’m being coy.
It seems to me that in order to even approach this question, I have to assume for the sake of argument that we both know what a Rhino is. Granting that, a rhino has all sorts of qualities that make it impossible for one to be in here- the floor wouldn’t hold him up, he’s too long, rhino’s aren’t invisible, they smell and make noises, so on and so forth. If you are asking me about an invisible, silent, light-weight good natured rhino, then you aren’t talking about a rhino at all, you’re asking me how do I know there’s not a mysterious demon in my room, which is another thing altogether.
If instead the problem is that I can’t see- maybe the room is larger, the elephant is visible, and my ability to acertain the world around me is limited to such a degree that there could be a rhino right here in front of me, and me not know it, then I think it’s only fair to take back the original ground I was giving, and ask
“What’s a rhino?”
Given that the equipment is sufficient for survival, it is calibrated within reasonable parameters for its function.
I can uncalibrate my equipment in a variety of ways, and we know that isn’t a very survivable phenotype. Look at schizophrenics, they have had their equipment seriously miscalibrated and they certainly have a very difficult time surviving.
My limited knowledge of Wittgenstein is that he was all about language/math.
If words are definied only by more words and language itself is observer-relative, how can we ever prove that there is an objective external observer-independent world?
What point is there in trying to prove to you that there is or is not a Rhino in the room if we just respond stating, “What is a Rhino?” We can infinitely ask for more definitions. But ultimately get no where because definitions and every word we speak is relative to us?
As I am always saying, using my caveman vocabulary, everything is a ‘grouping’. Everything relative is a massive network of interconnected references or ‘groupings’. You can never point at one thing to start with because it is reliant on references. It is a grouping. It is amazing that we can have the concept of zero or everything when every word or idea is a reference, not an actual thing.
Edit: Zero and everything are also ‘groupings’ or sets.
I’d be like, “What rhino?” too if I didn’t see it. But like, I wouldn’t ask what a rhino was 'cause I know what a rhino is. I’d ask if he changed the definition on me for the sake of confusion. He’d get bitch slapped.
It’s silly trying to prove existence comes from an objective reality when you’re standing in existence and this objective reality is coming from you.
Trying to prove the objective in the subjective realm has always seemed silly to me. If you want objective evidence, use objective means, i.e. get up off your ass and look, otherwise what is the point.
Furthermore I thi–oops… forgot to feed my Rhino, gotta run…
It depends on what you mean by “proof”. Absolute proof, in the sense that you show something to be true without any doubt, is not possible except in the limited context of mathematical/logical proofs. So there’s no absolute proof that something like a rhino exists in the room.
However, we mostly use the word “proof” to mean that you show something to be true without any reasonable doubt. In this case, you can prove that a rhino exists in the room, but it’s not that straightforward. First, you and the person to be shown the proof have to share a “common worldspace”. (That is the “shared reality” that Navigator referred to in his reply to you, Bane, in the discussion about mysticism.) Now this common worldspace includes a common understanding of what is a rhino - and this is exactly what Uccisore’s post is about, I think. Also note that it’s not the case that everyone will share this worldspace with you, e.g. a one-month-old baby will not know what’s a rhino, hence you cannot prove anything to him about a rhino. But once you’ve got someone who shares your understanding, you can prove that a rhino exists in the room… by pointing at it.
Look… from what perspective? Looking is relative, not objective. 
I’d like Wittgenstein to prove he existed, before I’d have to give a shit about his contrarian claptrap.
Now for real fun, who can prove this thread exists?
I was also thinking about the word “prove”. To prove anything is to make something relatively true for someone else. The whole goal of ‘proving’ is to make something that is relatively true to your understanding, relatively true to all others’ understandings.
I know that it is silly to ask for proof of objective reality, but do we all have to come back to the fact that we are assuming our “equipment” is “calibrated”? Is it as Navigator says, an assumption, of an assumption, of an assumption…?
Easy for the Wittgensteinian. You just point out that the question makes no sense if the thread does not exist.
Anyone?
Given the similarities of the human experience, as well as the extreme similarity between the equipment that humans come with (as well as our genetic similarity), I think that it would be absurd to assume anything other than a similar experience across the board. Casual discussions with other human beings affirm this, since we are all able to describe and experience things in incredibly similar manners.
So, barring defects, I think the burden of proof rests soundly on those who would argue that the experience isn’t so incredibly similar so as to render any discussion about the differences moot.
We can talk about how we take the experience, applying our own values to the situation, but we will all agree that vinegar is pungent and sour. Whether this is a pleasant experience or not is a matter of taste, but that which our senses send us is the same. It is our interpretation that differs.
is it really? I thought it wasn’t…
i mean…isn’t this a assumption too?
As some people know, this is one of my favorite subjects. I have spent long hours arguing in this area.
Mathematical proofs depend on certain “axioms”, which are statements that are assumed to be true. There’s no proof for these axioms, but they are the starting point for mathematical proofs. So in this regard you’re right, it’s all based on assumptions.
My point was that the mathematics field, compared to “real life”, is in a sense very simplistic, allowing very clear and precise axioms to be formed. And once you accept these axioms - which people must do when they do mathematics - absolute proof becomes possible, so that, for example, every mathematician will agree that 1 + 1= 2 is absolutely true.
Can you prove there’s a rhino in the room. Well, it depends on what you mean when you say “there’s a rhino in the room”.
Fundamentally we can’t prove that there’s any reality beyond our perceptions. Our perceptions justify their own existence, but they don’t prove the existence of anything beyond them. Me PERCEIVING a rhino proves that the perception exists, but it doesn’t prove that the rhino exists. Since that’s true for all perceptions, when we SAY “rhino”, you could reasonably argue that all we can plausibly mean is “the perception of …”. In that case, yes, you can prove that there’s a rhino in the room.
But if you mean, does there exist an object in objective reality which gave rise to my perception of a rhino, and that also had the properties that I perceived, then no, you can’t prove that.