From Steven Pressfield's The War of Art:
"Someone once asked the Spartan king Leonidas to identify the supreme warrior virtue from which all others flowed. He replied: 'Contempt for death.'
For us as artists, read 'failure.' Contempt for failure is our cardinal virtue. By confining our attention territorially to our own thoughts and actions - in other words, to the work and its demands - we cut the earth from beneath the blue-painted, shield-banging, spear-brandishing foe."
What a wonderfully Stoic idea, is it not? If we measure failure by the opinions of others, we are giving them power over us, valuing external indifferent things. Contempt of this . . . yes, in a way, this is close to a statement of the supreme virtue in Stoic thought as well . . .