I need to also be able to recognize them for what they are, but according to the skeptic we can't. — Michael
I think it is very reasonable to think that having evidence in favor of something simply consists in a. having in some sense a cognitive "access" to the evidence (and notice that in your example this requirement isn't met since you cannot read French, while in the perceptual case you can directly perceive your environment without further ado) and b. the evidence itself should in some sense guarantee the truth of what it is evidence for (and this requirement is met when you are having a waking experience, since in that case your cognitive state is very reliably correlated with the facts that you perceive). — Fafner
1. For any p, if a subject doesn’t have evidence which rule out (perhaps conclusively) the possibility of an error regarding p (that is, favor the possibility that p over not-p), then the subject doesn’t know that p.
2. Waking experience is indistinguishable from a very vivid dream (or a deception by an evil demon, or being a brain in a vat etc. – insert here your favorite skeptical scenario), since there are no distinct "marks" to distinguish the one from the other.
3. Therefore, for every p a subject can’t have evidence that favor p over not-p (from (2)).
4. Therefore, no p can be known (from (1) and (3)). — Fafner
Then let's change my example slightly. I am given a piece of paper that either has random symbols drawn onto it or Arabic writing. In either case I have cognitive "access" to the evidence; I can see it right in front of me. But I don't know if it's random symbols or Arabic writing. I need some second order understanding of how to distinguish the two. And with the case at hand, I need some second order understanding of how to distinguish a veridical and a non-veridical experience, which the skeptic claims we do not have. — Michael
In this case what you need is simply to know Arabic (or at least being able to reliably identify Arabic writing). And this is not "second order" evidence in my sense, because for you to know that you know (say) Arabic, all you need is simply the mere ability to read Arabic, and you don't need in addition some further ability to identify your own fluency in Arabic which is distinct from you just being fluent in the language. — Fafner
So knowing Arabic requires more than just being presented with Arabic words. Somehow I need to learn that these symbols are in fact Arabic words. And so knowing that our experiences are veridical requires more than just being presented with veridical experiences. Somehow I need to learn that these experiences are in fact veridical. — Michael
But, again, at best your argument is "if our experiences are veridical then we can know that our experiences are veridical", but given that the skeptic questions the antecedent, your argument would seem to beg the question. I could even turn your argument around and argue that because our experiences are not veridical we know that there isn't an external world (or at least none that we see). — Michael
But my point is that knowing that something is an Arabic script is inseparable from the ability to understand Arabic (that is, you cannot describe someone as being fluent in Arabic without presupposing that he can as a matter of fact read Arabic); and analogously, knowing that you are having a veridical experience is nothing but just having it as a matter of fact. — Fafner
You know that you are seeing a tree just by seeing a tree (and perhaps some other conditions like the absence of fake tree facades in the vicinity, re the Gettier problem)
This is why I called it a "version" of his argument, and my aim wasn't to correctly represent his actual philosophical views. And in any case, my argument does show that we can (in some sense) acquire certainty about the world, since being in a waking state does actually logically entail that you cannot be in error about what you perceive. — Fafner
Hence the skeptic cannot for his argument presuppose at the same time the conceptual distinction between waking and dreaming states, and also treat them as if they were the same. — Fafner
the way things appear to you when you are awake usually matches very closely the way they really are.... — Fafner
You're not comparing like for like here. Simply having a veridical experience is comparable to simply being shown an Arabic word. Just as the latter isn't the same as understanding Arabic, the former isn't the same as knowing that the experience is veridical. — Michael
To offer another example, let's say that I'm shown a painting, which may or may not be a forgery. You seem to be suggesting that if it's the real painting then I know that it's the real painting, or if it's the forgery then I know that it's the forgery. But that's just not right. The fact that it is or isn't the real painting isn't sufficient to claim knowledge that it is or isn't the real painting. And so the fact that it is or isn't a veridical experience isn't sufficient to claim knowledge that it is or isn't a veridical experience. — Michael
the way things appear to you when you are awake usually matches very closely the way they really are.... — Fafner
But the sceptic will say that this simply begs the question, i.e. assumes what it sets out to prove. If one's life were a perfectly well-ordered and consistent dream state, then the correlation between experience and the objects of perception could likewise be perfectly consistent and empirically verifiable. Even if fundamental physical constants were actually part of an illusion, provided they were consistent, then they would still make accurate predictions. — Wayfarer
The difference is this: a non expert cannot visually distinguish forgeries from non-forgeries, while we all can in most cases distinguish trees from non-trees. — Fafner
But we can't distinguish between a veridical experience of a tree and a non-veridical experience of a tree (or so the sceptic claims), and so the analogy holds.
I just don't know if right now I'm being deceived by an evil demon. — Michael
And you can make that distinction on the basis of the nature and quality of experience - that the experience of waking and dreaming is qualitatively different. — Wayfarer
The whole point is that there is no subjective differences between waking and dreaming states, otherwise, how appeal to dreams supposed to prove skepticism? — Fafner
As I then desired to give my attention solely to the search after truth, I thought … I ought to reject as absolutely false all opinions in regard to which I could suppose the least ground for doubt, in order to ascertain whether after that there remained [anything at all] in my belief that was wholly indubitable. Accordingly, seeing that our senses sometimes deceive us, I was willing to suppose that there existed nothing really such as they presented to us … [T]he very same thoughts (presentations) which we experience when awake may also be experienced when we are asleep, while there is at that time not one of them true, I supposed that all the objects (presentations) that had ever entered into my mind when awake, had in them no more truth than the illusions of my dreams. But immediately upon this I observed that, whilst I thus wished to think that all was false, it was absolutely necessary that I, who thus thought, should be somewhat; and as I observed that this truth, I think, therefore I am (cogito ergo sum), was so certain and of such evidence that no ground of doubt, however extravagant, could be alleged by the sceptics capable of shaking it. 1
Mere inability to distinguish on subjective grounds all non-veridical states from veridical proves absolutely nothing about ones knowledge of the world. Again look at the original argument — Fafner
There's no mention of waking and dreaming states, simply the observation that things appear real to us in dreams, yet are not, so, likewise, the reality of things that appear to our senses may be doubted. This is what leads directly to the famous declaration cogito, ergo sum. — Wayfarer
Sure, it's logically possible that life - by analogy - has the structure of a dream, but we really have no reason to suppose so (at least in our ordinary consciousness). Lacking a reason to suppose so means that doubting it would be irrational. Much more, within the waking state we come to know about the distinction between awake and dreaming, hence if even being awake is dreaming, then we have destroyed the notion of awake - and hence the notion of dreaming, which also depends on the notion of being awake. Language is rendered meaningless by such skepticism.The problem I see is that it is still feasible that the waking state, the state of presumed normality, is still a consistent illusion. It would be logically possible that, at the time of death, one is suddenly roused as if from a sleep, to a mode of existence that one had never guessed at while alive, but which now is obvious once again; one might immediately begin to forget the life you had just lived, in the same way as forgetting dreams that you have just had woken from. — Wayfarer
I've already addressed it. It's epistemic luck, not knowledge. Unless you can distinguish between a veridical and a non-veridical experience (or between a real painting and a forgery) then you can't know that your experiences are veridical (or if the painting is real). — Michael
Sure, it's logically possible that life - by analogy - has the structure of a dream, but we really have no reason to suppose so (at least in our ordinary consciousness). Lacking a reason to suppose so means that doubting it would be irrational. Much more, within the waking state we come to know about the distinction between awake and dreaming, hence if even being awake is dreaming, then we have destroyed the notion of awake - and hence the notion of dreaming, which also depends on the notion of being awake. Language is rendered meaningless by such skepticism. — Agustino
No you can't. Meanings are developed based on experience. If you categorize the experience of being awake as being equivalent to the experience of dreaming, then the meaning of awake and dreaming collapses. To avoid that collapse you'd need to have - in your experience - some other state in reference to which being awake is a dream. Lacking any such experience would render your terms meaningless.This is just pedantry. You can always accept the meaningful distinction between wakefulness (experiences of an external world) and dreaming (experiences not of an external world) but claim that those experiences which we claim to be of wakefulness aren't actually so. — Michael
So you cannot know that my belief that I see a tree is merely lucky if you don't know whether in fact there is a tree in front of me (and perhaps also whether my ability to detect trees in general is genuinely reliable). But of course the skeptic doesn't claim to know that there are in fact no trees (if he wished to prove that my believe is merely lucky), so it would be of little help to appeal to epistemic luck on his behalf. — Fafner
No you can't. Meanings are developed based on experience. If you categories the experience of being awake as being equivalent to the experience of dreaming, then the meaning of awake and dreaming collapses. — Agustino
If the meaning of awake no longer has a reference in experience, then that meaning has been destroyed. If you say that being awake is dreaming, then you have short-circuited your language.They're not equivalent. They're different. But neither are experiences of an external world. — Michael
If the meaning of awake no longer has a reference in experience, then that meaning has been destroyed. If you say that being awake is dreaming, then you have short-circuited your language. — Agustino
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