Combining Texts

All the ideas for 'Philosophical Explanations', 'Supervenience' and 'Ignorance: a Case for Scepticism'

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13 ideas

7. Existence / C. Structure of Existence / 5. Supervenience / a. Nature of supervenience
Supervenience: No A-difference without a B-difference [Bennett,K]
     Full Idea: The slogan for supervenience might be 'there cannot be an A-difference without a B-difference'. …(qualifying as a 'perfect forgery' would be an example).
     From: Karen Bennett (Supervenience [2011], Intro)
     A reaction: The key point about supervenience is that it is one-way. Presumably 'tracking' would be a better single word for it than 'dependence', which implies some sort of causal power. Supervenience describes, but doesn't attempt to explain.
Supervenience is non-symmetric - sometimes it's symmetric, and sometimes it's one-way [Bennett,K]
     Full Idea: Supervenience is neither symmetric nor asymmetric; it is non-symmetric. Sometimes it holds symmetrically. …And sometimes it holds asymmetrically.
     From: Karen Bennett (Supervenience [2011], §3.2)
     A reaction: I think of supervenience as 'tracking'. Stalkers track victims; married couples track one another. Beauty tracks statues, but statues don't seem to track beauty. I take so-called mind-brain supervenience to be two-way, not one-way.
7. Existence / C. Structure of Existence / 5. Supervenience / b. Types of supervenience
Weak supervenience is in one world, strong supervenience in all possible worlds [Bennett,K]
     Full Idea: Weak supervenience says there is no possible world that contains individuals that are B-indiscernible but A-discernible. Strong supervenience entails the same even if they are in different possible worlds.
     From: Karen Bennett (Supervenience [2011], §4.1)
     A reaction: In other words (I presume), in simple language, the weak version says they happen supervene, the strong version says they have to supervene.
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
Aesthetics, morality and mind supervene on the physical? Modal on non-modal? General on particular? [Bennett,K]
     Full Idea: It has been claimed that aesthetic, moral and mental properties supervene upon physical properties, …and that modal truths supervene on non-modal ones, and that general truths supervene on particular ones.
     From: Karen Bennett (Supervenience [2011], Intro)
     A reaction: I am attracted to the last bit. I am bewildered by people who try to derive particular truths from general ones, such as deriving physical behaviour from laws, or the nature of some creature simply from its species. Only some tigers are man-eaters.
Some entailments do not involve supervenience, as when brotherhood entails siblinghood [Bennett,K]
     Full Idea: Some entailments do not suffice for supervenience. Being a brother entails being a sibling, but being a sibling does not supervene on being a brother. Sarah has a sister and Jack in an only child. Sarah, unlike Jack, is a sibling; neither is a brother.
     From: Karen Bennett (Supervenience [2011], §3.2)
     A reaction: The whole point of supervenience, I take it, is to label a relation of tracking, while offering no explanation of the tracking. Entailment would be a rather powerful explanation, as would a dog's being tied to a cart.
Reduction requires supervenience, but does supervenience suffice for reduction? [Bennett,K]
     Full Idea: Everyone agrees that reduction requires supervenience, …but the more interesting issue is whether supervenience suffices for reduction.
     From: Karen Bennett (Supervenience [2011], §3.3)
     A reaction: I think we should assume that there is a reason for every genuine case of supervenience (i.e. there are no cases of eternal or ubiquitious coincidence). One-way causation seems to give supervenience without reduction.
7. Existence / D. Theories of Reality / 6. Physicalism
Definitions of physicalism are compatible with a necessary God [Bennett,K]
     Full Idea: All definitions of physicalism are compatible with the existence of a necessarily existing God.
     From: Karen Bennett (Supervenience [2011], 5.4)
     A reaction: All the definitions seem to depend on all the facts covarying with the physical facts, so anything which is invariant (such as divine or platonic entities) will stand outside the definition. Physicalism is more like a credo about all facts whatever.
10. Modality / A. Necessity / 6. Logical Necessity
The metaphysically and logically possible worlds are the same, so they are the same strength [Bennett,K]
     Full Idea: Metaphysical necessity is just as strong as logical necessity in that the space of metaphysical possibility is exactly the same as the space of logical possibility: the logically possible worlds = the metaphysically possible worlds.
     From: Karen Bennett (Supervenience [2011], §3.1)
     A reaction: I think this is wrong. To be the 'same strength' there would also have to be the same number of logical as metaphysical truths, and I presume that is not the case. There are far more logical than metaphysical possibilities.
11. Knowledge Aims / A. Knowledge / 4. Belief / c. Aim of beliefs
Maybe knowledge is belief which 'tracks' the truth [Nozick, by Williams,M]
     Full Idea: Nozick suggests that knowledge is just belief which 'tracks the truth' (hence leaving out justification).
     From: report of Robert Nozick (Philosophical Explanations [1981]) by Michael Williams - Problems of Knowledge Ch. 2
13. Knowledge Criteria / C. External Justification / 4. Tracking the Facts
A true belief isn't knowledge if it would be believed even if false. It should 'track the truth' [Nozick, by Dancy,J]
     Full Idea: Nozick says Gettier cases aren't knowledge because the proposition would be believed even if false. Proper justification must be more sensitive to the truth ("track the truth").
     From: report of Robert Nozick (Philosophical Explanations [1981], 3.1) by Jonathan Dancy - Intro to Contemporary Epistemology 3.1
     A reaction: This is a bad idea. I see a genuine tree in my garden and believe it is there, so I know it. That I might have believed it if I was in virtually reality, or observing a mirror, won't alter that.
13. Knowledge Criteria / C. External Justification / 6. Contextual Justification / b. Invariantism
The meaning of 'know' does not change from courtroom to living room [Unger]
     Full Idea: There is no reason to suppose that the meaning of 'know' changes from the courtroom to the living room and back again; no more than for supposing that 'vacuum' changes from the laboratory to the cannery.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], 2.1)
     A reaction: I disagree. Lots of words change their meaning (or reference) according to context. Flat, fast, tall, clever. She 'knows a lot' certainly requires a context. The bar of justification goes up and down, and 'knowledge' changes accordingly.
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
No one knows anything, and no one is ever justified or reasonable [Unger]
     Full Idea: I argue for the thesis that no one ever knows about anything, ...and that consequently no one is ever justified or at all reasonable in anything.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], Intro)
     A reaction: The premiss of his book seems to be that knowledge is assumed to require certainty, and is therefore impossible. Unger has helped push us to a more relaxed and fallibilist attitude to knowledge. 'No one is reasonable' is daft!
13. Knowledge Criteria / D. Scepticism / 4. Demon Scepticism
An evil scientist may give you a momentary life, with totally false memories [Unger]
     Full Idea: The evil scientist might not only be deceiving you with his electrodes; maybe he has just created you with your ostensible memory beliefs and experiences, and for good measure he will immediately destroy you, so in the next moment you no longer exist.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], 1.12)
     A reaction: This is based on Russell's scepticism about memory (Idea 2792). Even this very train of thought may not exist, if the first half of it was implanted, rather than being developed by you. I cannot see how to dispute this possibility.