Post #2460877

¬∀x P(x) ≠ ¬∃x P(x) Existential qualification is about as undefeated as father time. Just one example of a thing existing negates all claims that no such thing exists. Conversely, universal qualification is as brittle as they come. But. Humans suck at predicate logic. Even those who studied it still suck at it in everyday contexts, which is incidentally about the single most robust finding standing the test of time from Kahnemann's Thinking Fast And Slow. https://en.wikipedia.org/wiki/Existential_quantification