1. If I know that p, then there are no genuine grounds for doubting that p.
2. U is a genuine ground for doubting that p.
3. Therefore, I do not know that p. — Klein, 2014, Skepticism, SEP
Do you think the argument is a decisive objection those who think belief in the mind-independent existence of the world is justified? — Aaron R
I'm one of the realists around here. I don't think it's a decisive objection at all. One big problem with it is that it confuses the conceivability that not-p, or the coherent possibility of doubting that p with grounds for doubting that p. Grounds for something need to be more than conceivability or coherent possibility. After all, just as it's possible that one is merely dreaming that p, it's also possible that "one is dreaming that p" is false just as well. So if possibility is sufficient for belief, it's required that one believe contradictory claims, p and not-p, for almost every claim. — Terrapin Station
The argument apparently traces its roots to Pyrrohnian skepticism, — Aaron R
Pyrrho summarized his philosophy as follows: "Whoever wants to be happy (eudaimonia) must consider these three questions: First, how are pragmata (ethical matters, affairs, topics) by nature? Secondly, what attitude should we adopt towards them? Thirdly, what will be the outcome for those who have this attitude?" Pyrrho's answer is that "As for pragmata they are all adiaphora (undifferentiated by a logical differentia), astathmēta (unstable, unbalanced, not measurable), and anepikrita (unjudged, unfixed, undecidable). Therefore, neither our sense-perceptions nor our doxai (views, theories, beliefs) tell us the truth or lie; so we certainly should not rely on them. Rather, we should be adoxastous (without views), aklineis (uninclined toward this side or that), and akradantous (unwavering in our refusal to choose), saying about every single one that it no more is than it is not or it both is and is not or it neither is nor is not.
Adiaphora, astathmēta, and anepikrita are similar to the Buddhist Three marks of existence, suggesting that Pyrrho's teaching is based on what he learned in India, which is what Diogenes Laertius reported. — Wikipedia
The notion that everything might be a dream is doubly incoherent; both in terms of our linguistic usages and beyond that as well. — John
You even say it here yourself: in principle if not in practice. That "in principle" is thus a quite limited argument when it goes against practice. — ssu
Leibniz's Law is a bi-conditional that claims the following: Necessarily, for anything, x, and anything, y, x is identical to y if and only if for any property x has, y has, and for any property y has, x has.
That's a bad argument. You shouldn't ask for justification of belief in the existence of an external world under the assumption that the external world doesn't exist, or that we would never encounter the external world, only our own internal constructs.The dream argument attempts to demonstrate that belief in the existence of an "external" world is never justified. — Aaron R
What properties does one have that the other doesn't? — Mongrel
You can fly off the dream table, or it could turn into something else.
On the other hand you probably cannot choose to do a comprehensive spectroscopic and carbon dating analysis of the dream table or have it be reliably there for use for the next twenty years. — John
Perhaps I can help. It occurs to me that if one looks at the issue in terms of the occurrence of being, rather than the experience of that being, there is equivalence. So in a dream, a being finds herself in a dream. Likewise upon birth a being finds herself in a world. Irrespective of whether there are circumstances in experience to suggest that a being in a dream is caused by something in experience, empirical( a birth might likewise have a full complement of causes, which we are not aware of).These two instances of a being finding themselves somewhere are the same. Like a process of waking up, a being arrives somewhere through an unknown process, one ocassion a dream and another a birth into a world.I thought we'd see more defenders of the argument (or some variation of it). Ah well.
That it's a contradiction to believe two opposing things is not that it's a contradiction to claim that neither thing is sufficiently justified. — Michael
So what? How in the world are you getting from that question and my response that I was saying something about it being a contradiction to say that neither thing is sufficiently justified? — Terrapin Station
Klein, in his SEP article on skepticism, contends that the Dream argument conforms to the following schema:
1. If I know that p, then there are no genuine grounds for doubting that p.
2. U is a genuine ground for doubting that p.
3. Therefore, I do not know that p. — Klein, 2014, Skepticism, SEP — Aaron R
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