Keats addresses his poem “ode on a grecian urn” to the urn itself, using the poetic technique of apostrophe. how does this technique illustrate the immortality of art? use examples from the poem to support your answer.

The scene Keats describes on the urn has a special vibrancy because it conjures a living scene with an implied past and present. While the decoration depicts something alive, the poem attributes special beauty to the scene because it will never be altered by changes that come with the passing of time.

In the third line of the poem, the urn is called a “sylvan historian,” suggesting that it naturally communicates a story more effectively than we who live in the changing world can with "our rhyme":

Thou still unravish'd bride of quietness,

Thou foster-child of silence and slow time,

Sylvan historian, who canst thus express

A flowery tale more sweetly than our rhyme:

The reference to the urn as a "still unravish'd bride of quietness" is echoed later in the poem when Keats addresses a "fair youth" who can never kiss his love because he can't move forward in time to that event. And yet, the poem rejoices in the beauty he can enjoy forever. She won't fade, or cease to be fair (lose her youthful beauty), and his love will go on forever:

Bold Lover, never, never canst thou kiss,

Though winning near the goal yet, do not grieve;

She cannot fade, though thou hast not thy bliss,

For ever wilt thou love, and she be fair!

The world shown on the urn is also silent because it is fixed in time. The poem contrasts the "heard melodies" of our world with the even sweeter "unheard" ones that a viewer of the urn can imagine coming out of the "soft pipes" that play "to the spirit ditties of no tone" rather than to the "sensual ear" of mortal humans.

Finally, the poem says that this "silent form" will remain after the humans of the current generation are long gone. The urn will therefore act for a long time as "a friend to man" reminding him that "Beauty is truth, truth beauty":

When old age shall this generation waste,

Thou shalt remain, in midst of other woe

Than ours, a friend to man, to whom thou say'st,

‘Beauty is truth, truth beauty,’—that is all

Ye know on earth, and all ye need to know.

Addressing the urn directly heightens the sense of beauty and vibrancy that the poetic speaker sees and enjoys from the scene painted on it. This use of apostrophe makes the emphatic appreciation of the scene depicted seem alive, truly a place of "happy, happy boughs" and "happy, happy love."