And again, this seems to be a failure to differentiate between what is true and what is believed. Things like three-tonne boulders do not care what one believes. What is true is quite independent of what one believes. — Banno

I don't disagree. But if idealism is true then surely this too is independent of what one believes about it? I am not an idealist - as you probably know. The three-tonne boulder may just be a simulation, but it can destroy me as I am a part of the simulation too. I think that's the idea. Now your question might be - so if it is indistinguishable from physicalism, what does it matter? Or you might just call BS?

I don't disagree. — Tom Storm

I know.

And yes, the difference between realism and idealism is not one that can be decided by observation or experiment. To my now unfashionable eye, the difference is between two ways of talking about how things are, the one in which there are unknown truths, and the other in which what is unknown does not have a truth value.

The clearest way to understand this difference is in terms of truth. A realist will claim that there are truths that are not known.

An idealist will claim that there cannot be unknown truths.

So let's take an example. Is there a teapot in orbit around Jupiter (an example from Russell)? We cannot be certain if there is or is not such a teapot. It seems unlikely, but we have not yet inspected every item in orbit around Jupiter.

A realist will say that nevertheless the statement "there is a teapot in orbit around Jupiter" is either true, or it is false.

An idealist will say that the statement "there is a teapot in orbit around Jupiter" is neither true nor false until some mind has made a determination.

Effectively, a realist differentiates between belief and truth, claiming that we can believe or disbelieve in a Jovian teapot, but that this is an entirely seperate issue to there being a Jovian teapot. An idealist will say that the very truth or falsity of there being a Jovian teapot is dependent on a mind variously believing, knowing, perceiving or more generally standing in some relation to that teapot. — Banno

Nice.

Exactly. And I experience other people through the material world the same as I experience a boulder (light, sound, etc). If I doubt that material world, I should question the existence of both. — PhilosophyRunner

Blame Descartes. If the source of all certainty is "I think therefore I am", then all there is, is what I think.

Mere logic cannot bring things into existence, but instead supposes them in order to talk about them. Hence, if all one supposes is one's own thought, solipsism follows.

So here is one place in which it matters, - do other folk exist, and hence have a claim on one's time and energy? An idealist might argue that since they cannot be certain of the existence of others, they owe others no regard.

My response, in outline, would be that "I think, therefore I am" can only be proposed if one also proposes a shared project that includes others; the cogito can only be framed in a public language that takes others, and a shared reality as given; a sort of holism, if you like.

Blame Descartes. If the source of all certainty is "I think therefore I am", then all there is, is what I think. — Banno

Yes, If the source of all certainty is "I think therefore I am," then all there is, is what I think. But there is no reason for me to infer from that quote you or anyone else thinks at all, any more than a boulder thinks.

Hence the destination of solipsism.

If I doubt that computers are real, should I also not doubt Banno is real? I experience Banno through my computer after all. How can I infer that Banno is a real conscious entity, if I doubt the medium through which I experience him (or her)?

the fact is that solipsism as a theory is irrefutable. And unprovable. If everything i experience is just within my own mind, including other people and their minds, it’s impossible to disprove it.

Of course I don’t live like that - just fun to think about.

An idealist might argue that since they cannot be certain of the existence of others, they owe others no regard. — Banno

In steel-manning most idealism I've encountered, it seems to me the argument is that all human beings exist - in as much as they are separate instantiations of consciousness - and the world as it appears must also be taken seriously as a misadventure can still 'end' this expression of consciousness. So functionally there is not much difference in how one would go about conducting one's life - the difference is down to the metaphysics.

the fact is that solipsism as a theory is irrefutable. — GLEN willows

Indeed. And I think it is highly unlikely that I wrote all those Beethoven symphonies and George Elliot novels. Not to mention Dan Brown... :vomit:

as far as I understand, Descartes considered the cogito as just the beginning. He then went on to try proving the existence of other minds and a material world, But to do so, he had to bring God in, which doesn’t fly with most people as a sound argument.

So the cogito remains as the only undeniable fact - but has been modified to “there is a thinking thing” as opposed to the word “I” which is problematic.

Real philosophers here jump in and correct my simplistic explanation.

it seems to me the argument is that all human beings exist - in as much as they are separate instantiations of consciousness — Tom Storm

Yep, hence the sort of pan-psyche that @Wayfarer seemed to favour.

the fact is that solipsism as a theory is irrefutable — GLEN willows

And yet it stands refuted not just in what we do but in how we think. If other minds do not exist, whence embarrassment, pride, envy?

thanks for the info on wayfarer!

see my definition. If “everything I experience is in my mind” - that would include all my feelings including the ones you mentioned. If I really believed Banno was a real person, it would make sense that you could embarrass me.

when Neo was in the matrix did he not have reactions like you mention?

Perhaps this needs clarification, subject and object stand or fall together, which means mutual dependence, take one away and the other ceases to be, SUBJECTIVELY. Subjectively is the only means we have of knowing a physical world whatsoever. Actually I do not know why this needs repeated, there is a good deal of clarity to the first post that is being challenged.

Yes my understanding of Descartes is similar to yours, though I too am by no means an expert on this.

I am not a solipsist in any way. However I am curious about those who doubt the realness of the material world yet accept the realness of other people's consciousness, given that the only interactions we have with other people's consciousnesses is via the material world. I see, hear, touch, etc other people - all material interactions. If I doubt those material interactions are real, surely it follows I must doubt other people are real?

My medium of interaction with other people is no different to my medium of interaction with boulders - material interactions like light, sound, etc. I do not tunnel directly into the consciousness of other people.

I think there is much beyond that line of thinking, to do with what it is to be convinced by a proof.

That a line of thinking does not lead to contradiction does not imply that it is correct. So even if one supposes that solipsism does not contradict itself, one ought not therefore conclude that it is true. So even if solipsism is neither refutable nor provable, it does not follow that it is correct.

Hence

Of course I don’t live like that — GLEN willows

is worth further consideration. That you are occasionally proud or embarrassed shows, rather than proves, that you reject solipsism.

The Matrix does not show idealism, since there is a real world containing our computer overlords and our pods and the rebels and so on. What little philosophical content the film has does not help the idealist case.

Subjectively is the only means we have of knowing a physical world whatsoever. — boagie

Which says nothing about what the world is like. "We only know what we know" tells us nothing.

Theres' the danger of Stove's Gem, the view that one only knows what one knows using one's mind, and hence one never knows the thing itself. One may only ever taste an oyster with ones tongue, so one can never taste the oyster itself.

However I am curious about those who doubt the realness of the material world yet accept the realness of other people's consciousness, given that the only interactions we have with other people's consciousnesses is via the material world. I see, hear, touch, etc other people - all material interactions. If I doubt those material interactions are real, how can I infer other people are real? — PhilosophyRunner

No. The idea is that physical sensation or matter is how consciousness seems when viewed from a particular perspective - it's like a dashboard or illusion simulated by mind. To more fully understand idealism and the arguments it would help to read some Bernado Kastrup or Donald Hoffman. They present the arguments in a more accessible way and with some humor. They specifically address the familiar and worn, 'I refute it thus!' of Samuel Johnson kicking a rock in response to Bishop Berkeley.

I didn’t say it was correct. I said it was irrefutable, and also unprovable. And the fact that I - or anybody - rejects solipsism doesn’t mean it isn’t true.

The idea is that physical sensation or matter is how consciousness seems when viewed from a particular perspective — Tom Storm

I get this. But how do I know other people are also not just an illusion simulated by my mind? For me experientially, it is only my consciousness that has a privileged position.

My experience of computers, Tom Storm and boulders are indistinguishable in that they are all part of this physical dashboard I experience. It makes no sense for me to privilege Tom Storm as a conscious entity over the rest. They are all just inputs in the dashboard I experience.

However It does make sense for me to privilege my own consciousness, as that is the consciousness that I inhabit and experience directly (a la the Descartes quote). Hence the resultant solipsism.

I lean towards a form of realism. But in these last few posts I'm not arguing either for solipsism or realism or idealism. Rather I am arguing that if one were to subscribe to idealism, that should necessarily lead to solipsism (though I subscribe to neither).

Also thanks for the references to read Kastrup and Hoffman, I'll check them out.

I didn’t say it was correct. — GLEN willows

And I didn't say you said it was correct...

And the fact that I - or anybody - rejects solipsism doesn’t mean it isn’t true. — GLEN willows

But you don't think it true...

Rogue AI? A lion that's (only) a hallucination can't kill you or can it?

Yes, but vide infra, Tom Storm's comment.

Idealism is true ... to an extent! You really don't want to doubt the external reality of a a 3-ton boulder rolling down the hill, straight at you.
— Agent Smith

But idealism doesn't say there are no risks in what we call the 'physical world'. The physical world is seen as a kid of dashboard of readings which make consciousness apprehensible (al la Donald Hoffman). In this view of idealism, you may still be harmed by things which present as physical to our dashboard system. They just aren't what we think they are. — Tom Storm

you said “ So even if solipsism is neither refutable nor provable, it does not follow that it is correct.”

My response was “I’m not saying it’s correct”. We’re agreeing on that. My contention is it’s irrefutable logically and unprovable logically or empirically.

And you said “But you don't think it true.” I don’t think god exists either. That doesn’t mean I’m right.
Gut instinct can be dead wrong. And I used to believe a material world was undeniable. No longer.

Anyway I think we’re off topic.

But how do I know other people are also not just an illusion simulated by my mind? For me experientially, it is only my consciousness that has a privileged position. — PhilosophyRunner

How do you know today isn't the first day of your life and all your memories are implants? The potential disruptive questioning one can pose regarding any version of reality is endless.

I am trying to get the idealist position right so I can fully understand (as much as I can be arsed) what it proports to tell us. Sure you can fire questions at it but you can do this to any metaphysical position.

My experience of computers, Tom Storm and boulders are indistinguishable in that they are all part of this physical dashboard I experience. It makes no sense for me to privilege Tom Storm as a conscious entity over the rest. They are all just inputs in the dashboard I experience.

However It does make sense for me to privilege my own consciousness, as that is the consciousness that I inhabit and experience directly (a la the Descartes quote). Hence the resultant solipsism. — PhilosophyRunner

Well stated. And you're right. I am giving idealists the benefit of the doubt in trying to steel man their account of the materialist illusion. Donald Hoffman, for instance, would be the first to agree that jumping off a 30 story building will probably kill you - except that death and what actually happened isn't what we think it is.

Most people will of course consider this to be tosh. I'm not so crazy about the idea myself. :wink:

It is a good indication that the materialist is not right in that things are not always just as they appear.
Why hello Banana!

How do you know today isn't the first day of your life and all your memories are implants? — Tom Storm

The thing is we don't know anything at all with absolute (i.e. decontextualized) certainty), but if I were to accept that the only reliable or plausible guide is what I think then since I think that what appears to me as the material world is real, then following that criterion, I should believe the material world is real. I also don't think that everything is just a product of my mind, therefore I should not accept solipsism, just because it, like any other stupid possibility I can imagine, cannot be dis-proven.

It is a good indication that the materialist is not right in that things are not always just as they appear. — boagie

And yet we know this... so we know that things are different to how they appear; hence, we know that there is a way things are.

That certainly does not count against materialism. It looks more like support for materialism.

Material world = thoughts of God all subsidiary minds interact with

If the source of all certainty is "I think therefore I am," then all there is, is what I think. — PhilosophyRunner

Descartes’ cogito was never meant to indicate the source of all certainty. That which is impossible to doubt is therefore certain, and there is but one irreducible instance for which the doubt of it is impossible, and from that, only one irreducibly certain “is”, is given. For whichever “I” there is that thinks, there is that and only that “I” that is certain absolutely.

Which serves of course, to prove being certain is inherently possible, and from which an upheaval in metaphysical doctrine ensued, insofar as there can now be something other than pure mathematics on which to ground truth, and even more importantly, how there can be truth without the empirical verifications mathematics requires.

From that, it does not follow that all there is, is what I think (there is). It is absurd to claim there is nothing other than what I, or humans in general, can think.

All that could possibly mean anything to me, is what I think, while true in itself, is a different story.

From that, it does not follow that all there is, is what I think (there is). It is absurd to claim there is nothing other than what I, or humans in general, can think. — Mww

Quite right.

And I happen to think that his dualism is often misunderstood. He thought he could explain the whole physical (non-mental) world in terms of mechanistic materialism, the view that the world is a giant clock.

But mechanistic materialism could not account for many aspects of the mental, including thought and the creative aspect of language use, which is why, as a scientist, he introduced a new principle, res cogitans, to attempt to account for what his mechanistic philosophy could not explain.

He was wrong in the end, but it was a sensible approach.