There are two types of people in this world: those who swoop up their accidentally dropped keys with no complaints and go along their merry way and those who, more often than not, can’t pick them up without cursing or letting out a big, miserable sigh.  An insignificant occurrence, yes, but it’s often the mundane incidents (a whining child, an on-the-fritz printer) that reveal how vastly different human temperaments can be, says Michael D.

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