Tranquility, contentedness, freedom from fear or disturbance according to Epicurus. This is the kind of attitude we would imagine would be held by Epictitus or a modern day Stoic. I recall a Quaker friend, a leader in the Friends social movement who, having lost an important initiative on behalf of a desperately poor group of citizens, remarked quietly that we should now see what we have learned from this. Ataraxia. Cool Hand Luke.
Ataraxia
Two Strikes 