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in reply to Re^4: "-e" and "-d" switches
in thread "-e" and "-d" switches

~( e -> d ).
"It is not the case that e necessarily implies d", would be the formalized English representation of that logical statement. Implication, within the Logical Calculus, is a fact. "does not necessarily imply" means, formally, "does not imply". That's the he problem with translating formal language to natural language and back again.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.