William Butler Yeats Quote

Grant me an old man's frenzy,
Myself must I remake
Till I am Timon and Lear
Or that William Blake
Who beat upon the wall
Till Truth obeyed his call;

A mind Michael Angelo knew
That can pierce the clouds,
Or inspired by frenzy
Shake the dead in their shrouds;
Forgotten else by mankind,
An old man's eagle mind.