Among the cruelest slaveries is mood, because we recognize neither the master nor the manacle.  In the first place we don’t notice our moods; in the second place we don’t notice that they have mastered us.

A common view has it that we have a moral duty to talk with everyone – that unless we are constantly in dialogue, we are both unreasonable and uncharitable.  On the contrary, sometimes both charity and reason require breaking off conversation.  Or even refusing to enter it.

In teaching classical works of ethics – say, Cicero’s On Duties -- one of the most difficult things to explain is the idea of the fitting.  Our ancestors considered it obvious to any decent mind that some things are rationally appropriate to a given situation, and others are not.  Instead, we take notions of what is fitting to be nothing but “manners.”