12 ideas
21695 | The set scheme discredited by paradoxes is actually the most natural one [Quine] |
Full Idea: Each proposed revision of set theory is unnatural, because the natural scheme is the unrestricted one that the antinomies discredit. | |
From: Willard Quine (The Ways of Paradox [1961], p.16) | |
A reaction: You can either takes this free-far-all version of set theory, and gradually restrain it for each specific problem, or start from scratch and build up in safe steps. The latter is (I think) the 'iterated' approach. |
21693 | Russell's antinomy challenged the idea that any condition can produce a set [Quine] |
Full Idea: In the case of Russell's antinomy, the tacit and trusted pattern of reasoning that is found wanting is this: for any condition you can formulate, there is a class whose members are the things meeting the condition. | |
From: Willard Quine (The Ways of Paradox [1961], p.11) | |
A reaction: This is why Russell's Paradox is so important for set theory, which in turn makes it important for the foundations of mathematics. |
21691 | Antinomies contradict accepted ways of reasoning, and demand revisions [Quine] |
Full Idea: An 'antinomy' produces a self-contradiction by accepted ways of reasoning. It establishes that some tacit and trusted pattern of reasoning must be made explicit and henceforward be avoided or revised. | |
From: Willard Quine (The Ways of Paradox [1961], p.05) | |
A reaction: Quine treats antinomies as of much greater importance than mere paradoxes. It is often possible to give simple explanations of paradoxes, but antinomies go to the root of our belief system. This was presumably Kant's intended meaning. |
21690 | Whenever the pursuer reaches the spot where the pursuer has been, the pursued has moved on [Quine] |
Full Idea: The Achilles argument is that (if the front runner keeps running) each time the pursuer reaches a spot where the pursuer has been, the pursued has moved a bit beyond. | |
From: Willard Quine (The Ways of Paradox [1961], p.03) | |
A reaction: Quine is always wonderfully lucid, and this is the clearest simple statement of the paradox. |
21689 | A barber shaves only those who do not shave themselves. So does he shave himself? [Quine] |
Full Idea: In a certain village there is a barber, who shaves all and only those men in the village who do not shave themselves. So does the barber shave himself? The barber shaves himself if and only if he does not shave himself. | |
From: Willard Quine (The Ways of Paradox [1961], p.02) | |
A reaction: [Russell himself quoted this version of his paradox, from an unnamed source] Quine treats his as trivial because it only concerns barbers, but the full Russell paradox is a major 'antinomy', because it concerns sets. |
21694 | Membership conditions which involve membership and non-membership are paradoxical [Quine] |
Full Idea: With Russell's antinomy, ...each tie the trouble comes of taking a membership condition that itself talks in turn of membership and non-membership. | |
From: Willard Quine (The Ways of Paradox [1961], p.13) | |
A reaction: Hence various stipulations to rule out vicious circles or referring to sets of the 'wrong type' are invoked to cure the problem. The big question is how strong to make the restrictions. |
21692 | If we write it as '"this sentence is false" is false', there is no paradox [Quine] |
Full Idea: If we supplant the sentence 'this sentence is false' with one saying what it refers to, we get '"this sentence is false" is false'. But then the whole outside sentence attributes falsity no longer to itself but to something else, so there is no paradox. | |
From: Willard Quine (The Ways of Paradox [1961], p.07) | |
A reaction: Quine is pointing us towards type theory and meta-languages to solve the problem. We now have the Revenge Liar, and the problem has not been fully settled. |
19727 | Reliabilist knowledge is evidence based belief, with high conditional probability [Comesaņa] |
Full Idea: The best definition of reliabilism seems to be: the agent has evidence, and bases the belief on the evidence, and the actual conditional reliability of the belief on the evidence is high enough. | |
From: Juan Comesaņa (Reliabilism [2011], 4.4) | |
A reaction: This is Comesaņa's own theory, derived from Alston 1998, and based on conditional probabilities. |
19725 | In a sceptical scenario belief formation is unreliable, so no beliefs at all are justified? [Comesaņa] |
Full Idea: If the processes of belief-formation are unreliable (perhaps in a sceptical scenario), then reliabilism has the consequence that those victims can never have justified beliefs (which Sosa calls the 'new evil demon problem'). | |
From: Juan Comesaņa (Reliabilism [2011], 4.1) | |
A reaction: That may be the right outcome. Could you have mathematical knowledge in a sceptical scenario? But that would be different processes. If I might be a brain in a vat, then it's true that I have no perceptual knowledge. |
19726 | How do we decide which exact process is the one that needs to be reliable? [Comesaņa] |
Full Idea: The reliabilist has the problem of finding a principled way of selecting, for each token-process of belief formation, the type whose reliability ratio must be high enough for the belief to be justified. | |
From: Juan Comesaņa (Reliabilism [2011], 4.3) | |
A reaction: The question is which exact process I am employing for some visual knowledge (and how the process should be described). Seeing, staring, squinting, glancing.... This seems to be called the 'generality problem'. |
7861 | Libet says the processes initiated in the cortex can still be consciously changed [Libet, by Papineau] |
Full Idea: Libet himself points out that the conscious decisions still have the power to 'endorse' or 'cancel', so to speak, the processes initiated by the earlier cortical activity: no action will result if the action's execution is consciously countermanded. | |
From: report of Benjamin Libet (Unconscious Cerebral Initiative [1985]) by David Papineau - Thinking about Consciousness 1.4 | |
A reaction: This is why Libet's findings do not imply 'epiphenomenalism'. It seems that part of a decisive action is non-conscious, undermining the all-or-nothing view of consciousness. Searle tries to smuggle in free will at this point (Idea 3817). |
6660 | Libet found conscious choice 0.2 secs before movement, well after unconscious 'readiness potential' [Libet, by Lowe] |
Full Idea: Libet found that a subject's conscious choice to move was about a fifth of a second before movement, and thus later than the onset of the brain's so-called 'readiness potential', which seems to imply that unconscious processes initiates action. | |
From: report of Benjamin Libet (Unconscious Cerebral Initiative [1985]) by E.J. Lowe - Introduction to the Philosophy of Mind Ch.9 | |
A reaction: Of great interest to philosophers! It seems to make conscious choices epiphenomenal. The key move, I think, is to give up the idea of consciousness as being all-or-nothing. My actions are still initiated by 'me', but 'me' shades off into unconsciousness. |