From chapter 8 of My Brother Michael by Mary Stewart:
Simon said slowly, those cool eyes vividly alive now, watching the younger man, “You’re partly right. The great men know where they are going; yes, and they get there, but surely it’s a case of driving themselves without pause, rather than juggernauting over all the opposition? You think Polonius was a prosy old bore–you brought him in, remember, not me. I don’t agree with him but do him the justice of looking at the end of the quotation. ‘To thine own self be true, …Thou canst not then be false to any man.’ If being true to oneself means ignoring the claims of other people then it simply doesn’t work, does it? No, your really great man–your Socrates–doesn’t drive along a straight path of his own cutting. He knows what the end is, yes, and he doesn’t turn aside from it, but all the way there he’s reckoning with whatever–and whoever–else is in his way. He sees the whole thing as a pattern, and his own place in it.”
I quoted, thinking back, “‘I am involved in Mankind’?”
“What’s that?” said Nigel.
“A quotation from John Donne, a poet who became Dean of vast. Paul’s. This comes from his Devotions … ‘No man is an island, entire of itself.’ He’s right. In the end it’s our place in the pattern that matters.”
“Yes, but the artist?” said Nigel almost fiercely. He’s different, you know he is. …Wouldn’t he be justified in doing almost anything to fulfill himself, if his art was worth it in the end?”
“The end justifies the means? As a working principle, never,” said Simon. “Never, never, never.”