Combining Texts

Ideas for 'How the Laws of Physics Lie', 'Symbolic Logic (with Langford)' and 'Logical Properties'

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3 ideas

10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
Modal logic began with translation difficulties for 'If...then' [Lewis,CI, by Girle]
     Full Idea: C.I.Lewis began his groundbreaking work in modal logic because he was concerned about the unreliability of the material conditional as a translation of 'If ... then' conditionals.
     From: report of C.I. Lewis (Symbolic Logic (with Langford) [1932]) by Rod Girle - Modal Logics and Philosophy 12.3
     A reaction: Compare 'if this is square then it has four corners' with 'if it rains then our afternoon is ruined'. Different modalities seem to be involved. We even find that 'a square has four corners' will be materially implied if it rains!
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Modality is not objects or properties, but the type of binding of objects to properties [McGinn]
     Full Idea: Modality has a special ontological category: it consists neither in objects (possible worlds theory) nor in properties (predicate modifier view), but items I have called 'modes', ..which can be hard/soft/rigid/pliable binding of objects to properties.
     From: Colin McGinn (Logical Properties [2000], Ch.4)
     A reaction: As so often, McGinn is very persuasive. Essentially he is proposing that modality is adverbial. He associates the middle view with David Wiggins.
10. Modality / E. Possible worlds / 1. Possible Worlds / b. Impossible worlds
If 'possible' is explained as quantification across worlds, there must be possible worlds [McGinn]
     Full Idea: If we replace modal words like 'possible' with quantification across worlds, clearly the notion of 'world' must exclude impossible worlds, otherwise 'possibly p' will be true if 'p' holds in an impossible world.
     From: Colin McGinn (Logical Properties [2000], Ch.4)
     A reaction: The point here, of course, is that the question is being begged of what 'possible' and 'impossible' actually mean.