John Keats's "Ode to a Nightingale" presents the general idea of the conflicted nature of life: pain/joy, pleasure/numbness, life/death, mortal/immortal, real/ideal.
The nightingale acts almost as a muse for the poet's reflections as he moves from his initial response to the song of the nightingale to the poet's distancing of himself from the bird in the final stanza.
For instance, in Stanza I the poet, whose
heart aches and a drowsy numbness pains/My sense, as though of hemlock
is touched by the bird's song, causing him to wish that he could reach a state of numb astraction with the bird and
,,,leave the world unseen, And with thee fade away into the forest dim
by becoming numb through drinking "a beaker full of the warm South."
As a transition into the next stanza, Keats repeats the word fade; however, fade moves into dissolve as Keats contemplates death, not just a numbness to pain as he moves to Stanza IV in which he tells the "darkling" that he has been
half in love with easeful Death," and "Now more than ever it seems rich to die,/To cease upon the midnight with no pain,/while thou art pouring forth thy sould aborad/In such an ectasy!
Here Keats separates himself from the nightingale as he realizes that the "immortal Bird" is not meant for death: There is a continuum for it as the "self-same song" has been heard by Ruth and others of the ages. He bids "Adieu!" to the bird as is "tolled" by the song back to his "sole self" and reminded of his mortality. With all these conflicting musings, Keats wonders in the last line of the ode if his thoughts are merely illusionary, "a waking dream."