Shakespeherian Rag

'Do
'You know nothing? Do you see nothing? Do you remember
'Nothing?'
I remember
Those are pearls that were his eyes. Look!.
'Are you alive, or not? Is there nothing in your head?'

But
O O O O that Shakespeherian Rag-
It's so elegant
So intelligent

Supposedly there was a pop song in 1922 called "The Shakespearean Rag."  I've never heard it, but supposedly it was very pithy, and, in the intellectual climate of the time, slightly insulting.  I suppose a parallel today would be Falco's "Rock Me, Amadeus," although that doesn't quite capture the trivilizing element of "The Shakespearean Rag."

Eliot is riffing on the idea that Modern people can only access the greatness of our predecessors in a stunted, fragmentary way.  In the example above, there is nothing in the speaker's head except for enduring fear and the wisps of ancient grandeur, which dissipate like so much smoke in a gale.