Things we didn't know

Isn't it amazing when you look back on your life and realize how time has passed.  It seems I've been taking an awfully lot for granted with photography.  I never really thought about the things I learned in grade school that I never thought about, yet, could barely make it through a darkroom session without them.  For instance; multiplication tables.  Do you know your multiplication tables?  I do because my dad made me!  But yet, I haven't decided whether they're applicable in the ordinary world.  Is photography so un-ordinary?