1) Moore has knowledge that he has two hands. 2) Moore infers from the fact that he has two hands, to the conclusion that there exists an external world. 3) Hence, Moore knows that an external world exists.
Having knowledge of something presupposes that there are good reasons (at least in many cases) to believe it, — Sam26
just because people (or Moore) say something is so, it doesn't follow that it is. However, Wittgenstein points out that what we need to ask, is whether the doubt makes sense. Doubting occurs in a language-game, and language-games have rules - later Wittgenstein will point out that a doubt that doubts everything is not a doubt. Some kinds of doubting make no sense, — Sam26
The most widely discussed charge is that they cannot act without belief (Apraxia Charge). In response, the skeptics describe their actions variously as guided by the plausible, the convincing, or by appearances. The notion of appearances gains great importance in Pyrrhonian skepticism, and poses difficult interpretive questions (Barney 1992). When something appears so-and-so to someone, does this for the skeptics involve some kind of judgment on their part? Or do they have in mind a purely phenomenal kind of appearing? The skeptical proposals (that the skeptic adheres to the plausible, the convincing, or to appearances) have in common their appeal to something less than full-fledged belief about how things are, while allowing something sufficient to generate and guide action. — https://plato.stanford.edu/entries/skepticism-ancient/
Or, two, "I know or am certain that such and such is the case." In the second case the word certain could replace the word know, i.e., they essentially mean the same thing. — Sam26
However, can we doubt the propositions Moore is using, and can we doubt them in Moore's contexts? — Sam26
Presupposes as used in this context means there is a justification for believing X, or rather a justification for making the claim that one knows that X is the case. — Sam26
Presuppositions are the ground. And if good, they're usually solid ground - until they change. — tim wood
In other words, the ‘realism’ which constitutes the target of Collingwood's critique is not the ontological thesis that there exist mind independent objects, but the epistemological thesis that there is such a thing as presuppositionless knowledge of reality. Collingwood's rejection of this realism develops out of an attempt to explain how forms of enquiry which make mutually exclusive absolute presuppositions can co-exist alongside one another. — https://plato.stanford.edu/entries/collingwood/
He attacked the neo-empiricist assumptions prevalent in early analytic philosophy and advocated a logical/epistemological transformation of metaphysics from a study of being or ontology to a study of the absolute presuppositions or heuristic principles which govern different forms of enquiry.
That just makes a mash of the meaning of the word. What do you imagine pre-suppose to mean? If I claim justification, then that is exactly not presupposing. See the problem? — tim wood
Why did Moore choose hands to make his point? — TheMadFool
However, in a later passage he seems to clarify what he has in mind. In paragraph 42 Wittgenstein speaks of the "mental state of conviction," and that this state of conviction is something that occurs regardless of whether a proposition is true or false. Wittgenstein seems to refer to it as a subjective state of certainty, and we observe this in the way people speak or gesticulate. The way we gesticulate will often show our convictions. Moore's claim to knowledge seems to be more in line with this subjective state of certainty, than with real knowledge claims. This will be developed more as we look at these passages. — Sam26
Would you have preferred a different body part? — Marchesk
Well, hands aren't exactly "external" reality are they? Hands are too me to be proof of anything other than me, no? — TheMadFool
Well, you might say your body is part of external reality. That you have a body moving about in the world proves there is a world. Some people want to argue the subjectivity/objectivity divide is false. It's all objective. Problem is it can go the other way and be all subjective.
So how do we know which one it is? — Marchesk
Where exactly is the boundary between internal reality and external reality — TheMadFool
Our perception. Hands have nerves, so they're part of it. — Marchesk
Isn't Moore's claim like an astronomer thinking stars, galaxies, giant gas clouds, space dust, etc. exist by just looking at her telescope? — TheMadFool
Where exactly is the boundary between internal reality and external reality? Presumably there is an internal reality since we're talking about external reality. Also, it seems to me that hands and other sensory organs are the interface between the internal and the external - a place, so to speak, where the external and the internal greet and converse with each other. Given this is so, I'd expect something other than bodily parts for a proof of the external world. :chin: — TheMadFool
If proof means something like 'argument or sufficient evidence for the truth of a proposition,' then it seems to me that the very concept of proof is social — path
Why does the skeptic not doubt the existence of the mental, of the inner? — path
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