13 ideas
21982 | I only wish I had such eyes as to see Nobody! It's as much as I can do to see real people. [Carroll,L] |
Full Idea: "I see nobody on the road," said Alice. - "I only wish I had such eyes," the King remarked. ..."To be able to see Nobody! ...Why, it's as much as I can do to see real people." | |
From: Lewis Carroll (C.Dodgson) (Through the Looking Glass [1886], p.189), quoted by A.W. Moore - The Evolution of Modern Metaphysics 07.7 | |
A reaction: [Moore quotes this, inevitably, in a chapter on Hegel] This may be a better candidate for the birth of philosophy of language than Frege's Groundwork. |
12432 | Explanation of necessity must rest on something necessary or something contingent [Hale] |
Full Idea: The dilemma is that to give the ultimate source of any necessity, we must either appeal to something which could not have been otherwise (i.e. is itself necessary), or advert to something which could have been otherwise (i.e. is itself merely contingent). | |
From: Bob Hale (The Source of Necessity [2002], p.301) | |
A reaction: [Hale is summarising Blackburn's view, and going on to disagree with it] Hale looks for a third way, but Blackburn seems to face us with quite a plausible dilemma. |
12434 | Why is this necessary, and what is necessity in general; why is this necessary truth true, and why necessary? [Hale] |
Full Idea: We must distinguish between explaining particular necessities and explaining necessity in general; and we ought to distinguish between explaining, in regard to any necessary truth, why it is true, and explaining why it is necessary. | |
From: Bob Hale (The Source of Necessity [2002], p.308) | |
A reaction: Useful. The pluralist view I associate with Fine says we can explain types of necessity, but not necessity in general. If we seek truthmakers, there is a special case of what adds the necessity to the truth. |
12435 | The explanation of a necessity can be by a truth (which may only happen to be a necessary truth) [Hale] |
Full Idea: My claim is that there are non-transitive explanations of necessities, where what explains is indeed necessary, but what explains the necessity of the explanandum is not the explanation's necessity, but its truth simpliciter. | |
From: Bob Hale (The Source of Necessity [2002], p.311) | |
A reaction: The big idea is to avoid a regress of necessities. The actual truths he proposes are essentialist. An interesting proposal. It might depend on how one views essences (as giving identity, or causal power) |
12433 | If necessity rests on linguistic conventions, those are contingent, so there is no necessity [Hale] |
Full Idea: If the alleged necessity, e,g, 2+2=4, really does depend upon a convention governing the use of the words in which we state it, and the existence of that convention is merely a contingent matter, then it can't after all be necessary. | |
From: Bob Hale (The Source of Necessity [2002], p.302) | |
A reaction: [Hale is citing Blackburn for this claim] Hale suggests replies, by keeping truth and meaning separate, and involving laws of logic. Blackburn clearly has a good point. |
12436 | Concept-identities explain how we know necessities, not why they are necessary [Hale] |
Full Idea: It seems to me that identity-relations among concepts have more to do with explaining how we know that vixens are female foxes etc., than with explaining why it is necessary, and, more generally, with explaining why some necessities are knowable a priori. | |
From: Bob Hale (The Source of Necessity [2002], P.313) | |
A reaction: Hale rejects the conceptual and conventional accounts of necessity, in favour of the essentialist view. This strikes me as a good suggestion of Hale's, since I agree with him about the essentialism. |
19544 | Closure says if you know P, and also know P implies Q, then you must know Q [Dretske] |
Full Idea: Closure is the epistemological principle that if S knows that P is true and knows that P implies Q, then, evidentially speaking, this is enough for S to know that Q is true. Nothing more is needed. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.25) | |
A reaction: [Dretske was the first to raise this issue] It is 'closure' because it applies to every case of Q, which is every implication of P that is known. The issue is whether we really do know all such Qs. Dretske doubts it. See his zebra case. |
19545 | We needn't regret the implications of our regrets; regretting drinking too much implies the past is real [Dretske] |
Full Idea: One doesn't have to regret everything one knows to be implied by what one regrets. Tom regrets drinking three martinis, but doesn't regret what he knows to be implied by this - that he drank 'something', or that the past is real. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.28) | |
A reaction: A nice case of analogy! He's right about regret. Perceptual and inferential knowledge have different grounds. To deny inferential knowledge seems to be a denial that modus ponens can be a justification. But MP gives truth, not knowledge. |
19547 | Reasons for believing P may not transmit to its implication, Q [Dretske] |
Full Idea: Some reasons for believing P do not transmit to things, Q, known to be implied by P. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.29) | |
A reaction: That seems true enough. I see someone limping, but infer that their leg is damaged. The only question is whether I should accept the inference. How can I accept that inference, but then back out of that knowledge? |
19546 | Knowing by visual perception is not the same as knowing by implication [Dretske] |
Full Idea: A way of knowing there are cookies in the jar - visual perception - is not a way of knowing what one knows to be implied by this - that visual appearances are not misleading. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.29) | |
A reaction: Why is the 'way of knowing' relevant? Isn't the only question that of whether implication of a truth is in infallible route to a truth (modus ponens)? If you know THAT it is true, then you must believe it, and implication is top quality justification. No? |
19548 | The only way to preserve our homely truths is to abandon closure [Dretske] |
Full Idea: The only way to preserve knowledge of homely truths, the truths everyone takes themselves to know, is to abandon closure. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.32) | |
A reaction: His point is that knowledge of homely truths seems to imply knowledge of the background facts needed to support them, which he takes to be an unreasonable requirement. I recommend pursuing contextualism, rather than abandoning closure. |
19549 | P may imply Q, but evidence for P doesn't imply evidence for Q, so closure fails [Dretske] |
Full Idea: The evidence that gives me knowledge of P (there are cookies in the jar) can exist without evidence for knowing Q (they are not fake), despite my knowing that P implies Q. So closure fails. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.33) | |
A reaction: His more famous example is the zebra. How can P imply Q if there is no evidence for Q? Maybe 'there are cookies in the jar' does not entail they are not fake, once you disambiguate what is being said? |
19550 | We know past events by memory, but we don't know the past is real (an implication) by memory [Dretske] |
Full Idea: The reality of the past (a 'heavyweight implication') ...is something we know to be implied by things we remember, but it is not itself something we remember. | |
From: Fred Dretske (The Case against Closure (and reply) [2005], p.35) | |
A reaction: If I begin to doubt that the past is real, then I must necessarily begin to doubt my ordinary memories. This seems to be the modus tollens of knowledge closure. Doesn't that imply that the modus ponens was valid, and closure is correct? |