Combining Texts

All the ideas for 'Reply to Hellman', 'Internal and External Reasons' and 'Naming and Necessity preface'

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10 ideas

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
16985 Possible worlds allowed the application of set-theoretic models to modal logic [Kripke]
     Full Idea: The main and the original motivation for the 'possible worlds analysis' - and the way it clarified modal logic - was that it enabled modal logic to be treated by the same set theoretic techniques of model theory used successfully in extensional logic.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18)
     A reaction: So they should be ascribed the same value that we attribute to classical model theory, whatever that is.
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
16982 A man has two names if the historical chains are different - even if they are the same! [Kripke]
     Full Idea: Two totally distinct 'historical chains' that be sheer accident assign the same name to the same man should probably count as creating distinct names despite the identity of the referents.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.08 n9)
     A reaction: A nice puzzle for his own theory. 'What's you name?' 'Alice, and Alice!'
9. Objects / F. Identity among Objects / 1. Concept of Identity
16981 With the necessity of self-identity plus Leibniz's Law, identity has to be an 'internal' relation [Kripke]
     Full Idea: It is clear from (x)□(x=x) and Leibniz's Law that identity is an 'internal' relation: (x)(y)(x=y ⊃ □x=y). What pairs (w,y) could be counterexamples? Not pairs of distinct objects, …nor an object and itself.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.03)
     A reaction: I take 'internal' to mean that the necessity of identity is intrinsic to the item(s), and not imposed by some other force.
9. Objects / F. Identity among Objects / 8. Leibniz's Law
4942 The indiscernibility of identicals is as self-evident as the law of contradiction [Kripke]
     Full Idea: It seems to me that the Leibnizian principle of the indiscernibility of identicals (not to be confused with the identity of indiscernibles) is as self-evident as the law of contradiction.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.03)
     A reaction: This seems obviously correct, as it says no more than that a thing has whatever properties it has. If a difference is discerned, either you have made a mistake, or it isn't identical.
10. Modality / C. Sources of Modality / 1. Sources of Necessity
16984 I don't think possible worlds reductively reveal the natures of modal operators etc. [Kripke]
     Full Idea: I do not think of 'possible worlds' as providing a reductive analysis in any philosophically significant sense, that is, as uncovering the ultimate nature, from either an epistemological or a metaphysical view, of modal operators, propositions etc.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.19 n18)
     A reaction: I think this remark opens the door for Kit Fine's approach, of showing what modality is by specifying its sources. Possible worlds model the behaviour of modal inferences.
10. Modality / D. Knowledge of Modality / 2. A Priori Contingent
9385 The very act of designating of an object with properties gives knowledge of a contingent truth [Kripke]
     Full Idea: If a speaker introduced a designator into a language by a ceremony, then in virtue of his very linguistic act, he would be in a position to say 'I know that Fa', but nevertheless 'Fa' would be a contingent truth (provided F is not an essential property).
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.14)
     A reaction: If someone else does the designation, I seem to have contingent knowledge that the ceremony has taken place. You needn't experience the object, but you must experience the ceremony, even if you perform it.
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
4943 Instead of talking about possible worlds, we can always say "It is possible that.." [Kripke]
     Full Idea: We should remind ourselves the 'possible worlds' terminology can always be replaced by modal talk, such as "It is possible that…"
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.15)
     A reaction: Coming from an originator of the possible worlds idea, this is a useful reminder that we don't have to get too excited about the ontological commitments involved. It may be just a 'way to talk', and hence a tool, rather than a truth about reality.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
16983 Probability with dice uses possible worlds, abstractions which fictionally simplify things [Kripke]
     Full Idea: In studying probabilities with dice, we are introduced at a tender age to a set of 36 (miniature) possible worlds, if we (fictively) ignore everything except the two dice. …The possibilities are abstract states of the dice, not physical entities.
     From: Saul A. Kripke (Naming and Necessity preface [1980], p.16)
     A reaction: Interesting for the introduction by the great man of the words 'fictional' and 'abstract' into the discussion. He says elsewhere that he takes worlds to be less than real, but more than mere technical devices.
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
9379 A sentence is obvious if it is true, and any speaker of the language will instantly agree to it [Quine]
     Full Idea: A sentence is obvious if (a) it is true and (b) any speaker of the language is prepared, for any reason or none, to assent to it without hesitation, unless put off by being asked so obvious a question.
     From: Willard Quine (Reply to Hellman [1975], p.206), quoted by Paul Boghossian - Analyticity Reconsidered §III
     A reaction: This comes from someone who is keen to deny a priori knowledge, but what are we to make of the expostulations "It's obvious, you idiot!", and "Now I see it, it's obvious!", and "It seemed obvious, but I was wrong!"?
20. Action / C. Motives for Action / 3. Acting on Reason / c. Reasons as causes
9284 Reasons are 'internal' if they give a person a motive to act, but 'external' otherwise [Williams,B]
     Full Idea: Someone has 'internal reasons' to act when the person has some motive which will be served or furthered by the action; if this turns out not to be so, the reason is false. Reasons are 'external' when there is no such condition.
     From: Bernard Williams (Internal and External Reasons [1980], p.101)
     A reaction: [compressed] An external example given is a family tradition of joining the army, if the person doesn't want to. Williams says (p.111) external reason statements are actually false, and a misapplication of the concept of a 'reason to act'. See Idea 8815.