Combining Texts

All the ideas for 'Counterpart theory and Quant. Modal Logic', 'Ars Magna' and 'Epistemic Operators'

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10 ideas

5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Lull's combinatorial art would articulate all the basic concepts, then show how they combine [Lull, by Arthur,R]
     Full Idea: Lull proposed a combinatorial art. He wanted to reconcile Islam and Christianity by articulating the basic concepts that their belief systems held in common, and then inventing a device that would allow these concepts to be combined.
     From: report of Ramon (Ars Magna [1305]) by Richard T.W. Arthur - Leibniz 2 Intro
     A reaction: Leibniz's Universal Characteristic was an attempt at continuing Lull's project. Lull's plan rested on Aristotle's categories.
9. Objects / D. Essence of Objects / 1. Essences of Objects
Aristotelian essentialism says essences are not relative to specification [Lewis]
     Full Idea: So-called 'Aristotelian essentialism' is the doctrine of essences not relative to specifications.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], III)
     A reaction: In other words, they are so-called 'real essences', understood as de re. Quine says essences are all de dicto, and relative to some specification. I vote for Aristotle.
10. Modality / A. Necessity / 7. Natural Necessity
Causal necessities hold in all worlds compatible with the laws of nature [Lewis]
     Full Idea: Just as a sentence is necessary if it holds in all worlds, so it is causally necessary if it holds in all worlds compatible with the laws of nature.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], V)
     A reaction: I don't believe in the so-called 'laws of nature', so I'm not buying that. Is there no distinction in Lewis's view between those sentences which must hold, and those which happen to hold universally?
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
It doesn't take the whole of a possible Humphrey to win the election [Lewis]
     Full Idea: Even if Humphrey is a modal continuant, it doesn't take the whole of him to do such things as winning.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], Post B)
     A reaction: This responds to Kripke's famous example, that people only care about what happens to themselves, and not to some 'counterpart' of themselves.
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
Counterpart theory is bizarre, as no one cares what happens to a mere counterpart [Kripke on Lewis]
     Full Idea: Probably Humphrey could not care less whether someone else, no matter how much resembling him, would have been victorious in another possible world. Thus Lewis's view seems even more bizarre that the usual transworld identification it replaces.
     From: comment on David Lewis (Counterpart theory and Quant. Modal Logic [1968]) by Saul A. Kripke - Naming and Necessity notes and addenda note 13
     A reaction: I begin to see this as a devastating reply to a theory I previously found quite congenial.
Counterparts are not the original thing, but resemble it more than other things do [Lewis]
     Full Idea: Your counterparts resemble you closely in content and context in important respects. They resemble you more closely than do the other things in their worlds. But they are not really you.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], I)
     A reaction: It is a dilemma. If my counterpart were exactly me, I couldn't contemplate possibly losing a leg, or my sanity. But if my counterpart isn't exactly me, then I don't have much interest in its fate. Only essences can save us here. Cf. me tomorrow.
If the closest resembler to you is in fact quite unlike you, then you have no counterpart [Lewis]
     Full Idea: If whatever thing in world w6 it is that resembles you more closely than anything else in w6 is nevertheless quite unlike you; nothing in w6 resembles you at all closely. If so, you have no counterpart in w6.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], I)
     A reaction: This is the nub, because the whole theory rests on deciding whether two things resemble sufficiently 'closely'. But then we need a criterion of closeness, so we must start talking about which properties matter. Essences loom.
Essential attributes are those shared with all the counterparts [Lewis]
     Full Idea: An essential attribute of something is an attribute it shares with all its counterparts.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], III)
     A reaction: I don't like this. It ties essence entirely to identity, but I think essence precedes identity. Essence is a nexus of causal and explanatory powers which bestows an identity on each thing. But essence might be unstable, and identity with it.
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / c. Knowledge closure
You have knowledge if you can rule out all the relevant alternatives to what you believe [Dretske, by DeRose]
     Full Idea: The 'Relevant Alternatives' theory of knowledge said the main ingredient that must be added to true belief to make knowledge is that one be in a position to rule out all the relevant alternatives to what one believes.
     From: report of Fred Dretske (Epistemic Operators [1970]) by Keith DeRose - Intro: Responding to Skepticism §6
     A reaction: Dretske and Nozick are associated with this strategy. There will obviously be a problem in defining 'relevant'. Otherwise it sounds quite close to Plato's suggestion that we need true belief with 'logos'.
28. God / A. Divine Nature / 3. Divine Perfections
Nine principles of God: goodness, greatness, eternity, power, wisdom, will, virtue, truth and glory [Lull, by Arthur,R]
     Full Idea: Lull restricted himself to only nine 'absolute principles' of God: goodness, greatness, eternity, power, wisdom, will, virtue, truth and glory
     From: report of Ramon (Ars Magna [1305]) by Richard T.W. Arthur - Leibniz 2 'Combinatorics'
     A reaction: Leibniz responded that God's perfections are infinite in number, and thus beyond human comprehension. Lull cut them down to nine, because he was designing a sort of conceptual logic that employed them.