"To be a true artist," part 2

Michael Greenberg's Salinger essay, linked to in the post immediately below, reminds me of the poem "To a Friend whose Work has come to Nothing," by W.B. Yeats, whose 145th birthday was yesterday:

NOW all the truth is out,
Be secret and take defeat
From any brazen throat,
For how can you compete,
Being honour bred, with one
Who, were it proved he lies,
Were neither shamed in his own
Nor in his neighbours’ eyes?
Bred to a harder thing
Than Triumph, turn away
And like a laughing string
Whereon mad fingers play
Amid a place of stone,
Be secret and exult,
Because of all things known
That is most difficult.