3 ideas
| 7803 | 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! |
| 7331 | A theory of meaning comes down to translating sentences into Fregean symbolic logic [Davidson, by Macey] |
| Full Idea: For a theory of meaning for a fragment of natural language, what Davidson requires, in effect, is that the sentences be translatable into the language of Frege's symbolic logic. | |
| From: report of Donald Davidson (In Defence of Convention T [1973]) by David Macey - Penguin Dictionary of Critical Theory | |
| A reaction: This assumes the adequacy of Fregean logic, which seems unlikely. Is this the culmination of Leibniz's dream of a fully logical language - so that anything that won't fit into our logical form is ruled (logical positivist style) as meaningless? |
| 15640 | Courage is not a virtue, but the form of every virtue at its testing point [Lewis,CS] |
| Full Idea: Courage is not simply one of the virtues, but the form of every virtue at the testing point. | |
| From: C.S. Lewis (works [1950]) | |
| A reaction: This appeared on Twitter, without mention of its source. Adding it breaks my normal rules, but I hope you agree that it is too good to miss. Is not even resolutely facing up to suffering or death a case of genuine courage? Determination, prioritisation? |