Know Yourself - And Your Enemy

Is a single novel literally inexhaustible? Poul Anderson's A Knight Of Ghosts And Shadows seems to be. Certainly, when I have exhausted all that I can find to say about it this time, I will not have exhausted all that there is to be said about it. Of course, the novel expresses not only its author's conscious artifice while he is writing it but, beyond that, his total knowledge and creativity.

Aycharaych knows the Chereionite heritage that he preserves. See here. But does he also display an impossibly detailed knowledge of Earth? He mentions:

Bach and the St. Matthew Passion;
Rembrandt and his few daubs of paint;
Tu Fu's poetry of dead leaves, snow, departing cranes and an old, shabby, caged parrot;
"negotium perambulans in tenebris";
"Yet half a beast is the great god Pan..." (Chapter IX, pp. 460-464)

Also, earlier in Sir Dominic Flandry: The Last Knight Of Terra:

Johann Strauss' waltzes;
Richard Strauss' Death and Transfiguration;
Xingu (?). ("Hunters of the Sky Cave," II, p. 160) 

However, Aycharaych has studied his enemy, has secretly visited Earth to walk in forests, inspect paintings and visit graves (p. 161) and is a universal telepath.

"The Empire had never had a more dangerous single enemy." (p. 463)