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Ideas for 'How the Laws of Physics Lie', 'A Pragmatic Conception of the A Priori' and 'fragments/reports'

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2 ideas

5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
If everything is and isn't then everything is true, and a midway between true and false makes everything false [Aristotle on Heraclitus]
     Full Idea: The remark of Heraclitus that all things are and are not effectively renders all assertions true, and that of Anaxagoras that there is an intermediary between assertion and negation makes all assertions false.
     From: comment on Heraclitus (fragments/reports [c.500 BCE]) by Aristotle - Metaphysics 1012a
     A reaction: Compare Idea 416. Heraclitus is discussing truth-value 'gluts', as in paraconsistent logic, and Anaxagoras is discussing truth-value 'gaps', as in three-valued Kleene logic.
Excluded middle is just our preference for a simplified dichotomy in experience [Lewis,CI]
     Full Idea: The law of excluded middle formulates our decision that whatever is not designated by a certain term shall be designated by its negative. It declares our purpose to make a complete dichotomy of experience, ..which is only our penchant for simplicity.
     From: C.I. Lewis (A Pragmatic Conception of the A Priori [1923], p.365)
     A reaction: I find this view quite appealing. 'Look, it's either F or it isn't!' is a dogmatic attitude which irritates a lot of people, and appears to be dispensible. Intuitionists in mathematics dispense with the principle, and vagueness threatens it.