Philip Wadler doing Stand-Up in Edinburgh

This was in May 2015!

Four years later he shows up again, completely misrepresenting Aristotle. 

Why? Because what Aristotle wrote was that the same predicate could not be both asserted and denied of the same thing in the same sense at the same time. In ordinary propositional logic this is something like ¬(P∧¬P). That is not equivalent to the law of the excluded middle P∨¬P unless you use double-negation ¬¬P→P and de Morgan's law ¬(P∧Q)→(¬P∨¬Q), neither of which are intuitionistically valid. See weak excluded middle in nLab. You may now say that Aristotle wasn't an intuitionist, but Aristotle didn't do symbolic logic, so that is moot. 

Wadler deserves everything he gets (Feb 20, 2015) if you ask me! 

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It's all about judgement, this intuitionism. See Ways to Do Telecommunications. 

12:18 Teaching philosophy. 

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See More History of London. 

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