Read the analysis of a theme from "Ode on a Grecian Urn." One theme in "Ode on a Grecian Urn" is that art is an eternal and unchanging truth. Now, read the passage from Keats's poem "On Seeing the Elgin Marbles." So do these wonders a most dizzy pain, That mingles Grecian grandeur with the rude Wasting of old Time—with a billowy main— A sun—a shadow of a magnitude. The theme of the passage relates to the theme from "Ode on a Grecian Urn" by supporting it. contradicting it. summarizing it. illustrating it.