The mind requires inputs. Whether those inputs are external is not something that can be determined.

Of course, at this point I need to re-emphasize that "mind" here is not limited to the conscious mind. I can (for the sake of argument) acknowledge as self-evident that the inputs interpreted by the conscious mind do not come from the conscious mind itself. This is not evidence that they come from an "external world." They could as well come from something like the imagination.

But the point is that we don't know where they "come from." That is unknown, plain and simple. We can assume that they come from an external reality, but we can't rationally justify that assumption.

But the definitions don't support that. The definition from the link you posted states that solipsism is a form of skepticism and that its only claim is that knowledge of anything outside the mind is unjustified.

I mean something much broader by "mind" than you seem to be suggesting here.

I do not believe it is possible to know whether the outside world exists, much less whether it is autonomous.

Yes. "My mind" is not contained in myself, "myself" is contained in my mind. That basic awareness seems to clearly precede my sense of self (and certainly my sense of my unique identity). I don't believe in giving a posteriori a higher status than a priori.

I don't know that we "really" are having this conversation.

And as a result, I am full of doubts about such things.

I don't know I have a self, so if I am "everyone," then no one knows I have a self (even if I do, in fact, have a self).

We identify patterns. Identifying patterns in our experiences cannot tell us the nature of our experiences (this is the point tame disagreed with me on in another RGT thread).

Sure. A thought is itself just another input into the field of mind. Which is why I agree with bigmonkey that beliefs about mental states are closer to knowledge than analytic truths (and I would say that analytic truths rely on beliefs about mental states, or at least on the mental states themselves and their presumed validity).

There are many closed-minded people with high IQ and incredible intellectual achievements. I don't see any indication that thinking ability is closely linked to any kind of "openness."

Doesn't this unjustly render all hypotheses equally useless?

No, it only restricts all hypotheses to the framework of the mind.

Yowser, Madnak, i can only wish you well but then again, since there is some doubt as to whether we are having this conversation I'm not sure you'll receive the message. Therefore.................OK..............you think he's still there?...................

So you place no intrinsic value on whether something actually physically exists or not?

What I'm getting at is the fact that some ideas have utility in the "material world", whether it exists or not is moot. Others are just interesting mental constructs or downright useless.

Sure. Evaluating the utility of an idea in the physical world has nothing to do with whether the physical world really exists.

So if one idea or notion is superior to another we can say with some confidence that it is likely that stuff does infact exist, with a greater probability than it being illusory.

More succinctly: "It is impossible to justify a mind/world distinction."

It's important to understand that solipsism says nothing about brain/world or brain/brain distinctions. A solipsist ontology can list billions of distinct humans, or even indulge in a many-world interpretation of QM, and be completely consistent. Solipsism contradicts dualism. That's it.

I just skimmed the Deutsch link, but he doesn't seem to understand this.

Assuming a mind that perceives/generates a universe is not a more "improbable" proposition from assuming a universe that generates a mind, in any way.

The only reason you claim this must because you reliance on some perceived "complexity" notion that one must be more probable than the other, but this is exactly the territory where Kant shows how rationalism comes short - when it relies on empirical inquiry and can be used to disprove and prove itself at the same time.

[ ] understands Occam's Razor
[ ] understands Solipsism

Assuming a mind assumes at least a limited universe - the vat, or at least 'something' external to the mind to keep it operating. Unless you assume the mind is some completely self-sustaining, self-functioning unit.

-Zeno

Solispsism and the Problem of Other Minds:

http://www.iep.utm.edu/s/solipsis.htm

From the above link [Wittgenstein's objections or critique of solipsism from his Philosophical Investigations:


To put this slightly differently, a person is a living human being and the human person in this sense functions as our paradigm of that which has a mental life; it is precisely in relation to their application to persons that we learn such concepts as "consciousness," "pain," "anger," and so forth. As such, it is a necessary and antecedent condition for the ascription of psychological predicates such as these to an object that it should "possess" a body of a particular kind.

Wittgenstein articulated this point in one of the centrally important methodological tenets of the Investigations:

Only of a living human being and what resembles (behaves like) a living human being can one say: it has sensations; it sees; is blind; hears; is deaf; is conscious or unconscious. (I. § 281).

Consequently, the belief that there is something problematic about the application of psychological words to other human beings and that such applications are necessarily the products of highly fallible inferences to the "inner" mental lives of others, which require something like the argument from analogy for their justification, turns out to be fundamentally confused. The intersubjective world that we live with other human beings and the public language-system that we must master if we are to think at all are the primary data, the "proto-phenomena," in Wittgenstein's phrase. (I. § 654)

Our psychological and non-psychological concepts alike are derived from a single linguistic fountainhead. It is precisely because the living human being functions as our paradigm of that which is conscious and has a mental life that we find the solipsistic notion that other human beings could be "automatons," machines devoid of any conscious thought or experience, bizarre and bewildering. The idea that other persons might all in reality be "automatons" is not one which we can seriously entertain.

------------------------------------------------------------------


In another way, Wittgenstein seeks to undermine Solipsism by questioning the possibility that anyone could aquire a private language. At least that seems part of the sense of his reasoning. I don't know how much I agree or disagree with this position as yet.

-Zeno

Added in edit-

Also from the above link:


The Incoherence of Solipsism

With the belief in the essential privacy of experience eliminated as false, the last presupposition underlying solipsism is removed and solipsism is shown as foundationless, in theory and in fact. One might even say, solipsism is necessarily foundationless, for to make an appeal to logical rules or empirical evidence the solipsist would implicitly have to affirm the very thing that he purportedly refuses to believe: the reality of intersubjectively valid criteria and a public, extra-mental world. There is a temptation to say that solipsism is a false philosophical theory, but this is not quite strong or accurate enough. As a theory, it is incoherent. What makes it incoherent, above all else, is that the solipsist requires a language (that is a sign-system) to think or to affirm his solipsistic thoughts at all. Given this, it is scarcely surprising that those philosophers who accept the Cartesian premises that make solipsism apparently plausible, if not inescapable, have also invariably assumed that language-usage is itself essentially private. The cluster of arguments - generally referred to as "the private language argument" - that we find in the Investigations against this assumption effectively administers the coup de grâce to both Cartesian dualism and solipsism. (I. § 202; 242-315). Language is an irreducibly public form of life that is encountered in specifically social contexts. Each natural language-system contains an indefinitely large number of "language-games," governed by rules that, though conventional, are not arbitrary personal fiats. The meaning of a word is its (publicly accessible) use in a language. To question, argue, or doubt is to utilize language in a particular way. It is to play a particular kind of public language-game. The proposition "I am the only mind that exists" makes sense only to the extent that it is expressed in a public language, and the existence of such language itself implies the existence of a social context. Such a context exists for the hypothetical last survivor of a nuclear holocaust, but not for the solipsist. A non-linguistic solipsism is unthinkable and a thinkable solipsism is necessarily linguistic. Solipsism therefore presupposes the very thing that it seeks to deny. That solipsistic thoughts are thinkable in the first instance implies the existence of the public, shared, intersubjective world that they purport to call into question.


Interesting.

my mind is quite capable of several threads communicating via a language public over the mind.

Sometimes I even give then names like madnak and zeno, two of them are called Wittgenstein.

Right, neither assumption is justifiable. Thus, solipsism.

My reality is indistinguishable from the contents of my mind. Thus, "reality" in any sense that I can refer to it, means the same as "my mind," in the broadest sense that I can refer to it.

A computer cannot display the Eiffel Tower. A computer can only display a graphic representation of regions of its own memory. We, sitting external to the computer, can say that the graphic representation corresponds to the Eiffel Tower. But the computer cannot know that. The computer only receives its data - and the data itself is the only information it has about the source. It cannot tell the difference between a photograph and a sufficiently detailed fantasyscape.

We have a tendency to assume that we are different. But here, that's not the case. When I think of the Eiffel Tower, I am only accessing my memories of the Eiffel Tower. If I am standing under the Tower, looking up, then I can also access visual inputs of the Eiffel Tower. But I have no direct access to the Tower.

The argument from simplicity is an argument from utility, not an argument from utility, not an argument from probability. You (and Kant) are continuing to clearly miss the point based on those characterizations. Of course I'm not talking about the probability that solipsism is "really true;" I don't believe it is meaningful for me to talk about "really true" in the first place.

I don't have to assume anything. And solipsism explicitly suggests that neither premise is even meaningful, much less justified.

Wittgenstein's reasoning here is clearly circular, in much the same manner as Kant's. He assumes that humans are living beings (that only living being can be conscious). This is an assumption he has derived from his empiricism (and I would contend, his empirical dualism).

If he wants to show that solipsism is illogical, then he must demonstrate that solipsist conclusions contradict solipsist premises (which do not include the assumption that only living beings are capable of consciousness, or even the conception of "beings" whatever). You can't use an empiricist premise to contradict solipsism, as solipsism disputes (and I'd wager, refutes) empiricism.

The assumptions are perfectly justifiable. Reliance on observation is not a weaker concept than reliance on thought, you can't even make a case as for why one concept is more real than the other, so why make pretenses? There is no "justifiable proof" that thoughts are anything but indirect illusory effects of the same kind that perception is.

From a soliptic standpoint none of these things make sense. Why are you talking about the the Eiffel tower, computers or "we" when the existence of these things are not clear? Don't invoke empirical arguments to show why empirical arguments are not justifiable. Are you arguing that solipsism is an ontological argument?

It looks to me from zeno's quotes that Wittgensein is refuting Strong Solispsim. It's unclear whether his arguments go through as well versus madnak's weak solipsim, although I suspect they might still function.

Where do your words come from madnak?

PairTheBoard

Heres your problem; Infalibility. Any postulate which is deemed to be untestable is inherently weak. This is where solipsism (at least Madnaks' version) and the God hypothesis are on an equal footing.

Because you want to have your cake and eat it.

Solipsism doesn't make claims; empiricism does. You are the one claiming that there is an absolute reality, and as you are making the claim the onus is on you to test it. Funny enough, you can't test it - meaning that empiricism is, as you suggest, on the same footing as the God hypothesis.

Damn thats crass. If solipsism doesn't make claims then from what perspective have you based your assertions? Not a solipsist perspective, 'cause if thats so you can't have one.

By following the logic further, I will assume that assuming nothing, thinking nothing and observing nothing is the most philosophically true state possible. I'll empirically infer that SMP is thus intellectually surpassed by pebbles.