Granny Magda writes:
Cedre, common sense is the opposite of logic. You usually can't have both. Indeed. this may explain why you are having such trouble with these relatively simple concepts. Ditch the common sense. It isn't sensible.
One of the definitions of common:
Common: Of mediocre or inferior quality; second-rate
While that isn't the intended meaning in the phrase "common sense", when we see that phrase used around here it sure seems like it should be.
--Percy