If you hide A6 it causes A9 to go from proved (green) to contingent (black, i.e. could be true or false depending on the variable assignment.) This is because if Socrates we don't know whether Socrates exists, the statement "Socrates is not mortal", or "every socrates is not mortal" is true if Socrates does not exist and false if he does.
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If you hide A6 it causes A9 to go from proved (green) to contingent (black, i.e. could be true or false depending on the variable assignment.) This is because if Socrates we don't know whether Socrates exists, the statement "Socrates is not mortal", or "every socrates is not mortal" is true if Socrates does not exist and false if he does.
I wish I could edit comments. :-/
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