The speaker responds to the beauty of the nightingale’s song with a both “happiness” and “ache.” Though he seeks to fully identify with the bird — to “fade away into the forest dim” — he knows that his own human consciousness separates him from nature and precludes the kind of deathless happiness the nightingale enjoys.First the intoxication of wine and later the “viewless wings of Poesy” seem reliable ways of escaping the confines of the “dull brain,” but finally it is death itself that seems the only possible means of overcoming the fear of time. The nightingale is “immortal” because it “wast not born for death” and cannot conceive of its own passing. Yet without consciousness, humans cannot experience beauty, and the speaker knows that if he were dead his perception of the nightingale’s call would not exist at all. This paradox shatters his vision, the nightingale flies off, and the speaker is left to wonder whether his experience has been a truthful “vision” or a false “dream.” Referred to by critics of the time as "the longest and most personal of the odes," the poem describes Keats' journey into the state of Negative Capability. John Keats coined the phrase 'Negative Capability' in a letter to his brothers and defined his new concept of writing:
“that is when man is capable of being in uncertainties, Mysteries, doubts, without any irritable reaching after fact and reason”
Keats' poems are full of contradictions in meaning ('a drowsy numbness pains') and emotion ('both together, sane and mad') and he accepts a double nature as a creative insight. In ‘Nightingale’ it is the apparent (or real) contradictions that allow Keats to create the sensual feeling of numbness that allows the reader to experience the half-swooning emotion Keats is trying to capture. Keats would have us experience the emotion of the language and pass over the half-truths in silence, to live a life 'of sensations rather than of Thoughts!'. Thus, ‘Ode to the Nightingale’ is more feeling than a thinking poem. Keats often deals in the sensations created by words rather than meaning. Even if the precise definition of words causes contradiction they can still be used together to create the right ambience. Negative Capability asks us to allow the atmosphere of Keats' poems to surround us without picking out individual meanings and inconsistencies.
“That I might drink, and leave the world unseen”
Hearing the song of the nightingale, the speaker longs to flee the human world and join the bird. His first thought is to reach the bird's state through alcohol--in the second stanza, he longs for a "draught of vintage" to transport him out of himself. But after his meditation in the third stanza on the transience of life, he rejects the idea of being "charioted by Bacchus and his pards" and chooses instead to embrace "the viewless wings of Poesy." The rapture of poetic inspiration matches the endless creative rapture of the nightingale's music and lets the speaker, in stanzas five through seven, imagine himself with the bird in the darkened forest. The ecstatic music even encourages the speaker to embrace the idea of dying, of painlessly succumbing to death while enraptured by the nightingale's music and never experiencing any further pain or disappointment.
“Fade far away, dissolve, and quite forget
What thou among the leaves hast never known”
The poet explores the themes of nature and mortality. Here, the transience of life and the tragedy of old age is set against the eternal renewal of the nightingale's fluid music. Man has many sorrows to escape from in the world, and these Keats recounts feelingly in the third stanza of his poem, a number of the references apparently being drawn from firsthand experience. The mention of the youth who "grows pale, and spectre-thin, and dies," for example, might well be an allusion to Tom Keats, the younger brother whom the poet nursed through his long, last struggle with consumption. But the bitterest of all man's sorrows, as it emerges from the catalogue of woes in the third stanza, is the terrible disease of time, the fact that ‘Beauty cannot keep her lustrous eyes’. It is the disease of time which the song of the nightingale particularly transcends, and the poet, yearning for the immortality of art, seeks another way to become one with the bird. Even death is terribly final; the artists die but what remains is the eternal music; the very song heard today was heard thousands of years ago. The poet exclaims:
“Forlorn! the very word is like a bell
To toll me back from thee to my sole self!”
The reverie into which the poet falls carries him deep into where the bird is singing. But the meditative trance cannot last. With the very first word of the eighth stanza, the reverie is broken. The word “forlorn” occurs to the poet as the adjective describing the remote and magical world suggested by the nightingale’s song. But the poet suddenly realises that this word applies with greater precision to himself. The effect is that of an abrupt stumbling. With the new and chilling meaning of “forlorn”, the song of the nightingale itself alters: it becomes a “plaintive anthem”. The song becomes fainter. What had before the power to make the sorrow in man fade away from a harsh and bitter world, now itself “fades” and the poet is left alone in the silence. As the nightingale flies away, the intensity of the speaker's experience has left him shaken, unable to remember whether he is awake or asleep; thus "Adieu! the fancy cannot cheat so well”.
The "art" of the nightingale is endlessly changeable and renewable; it is music without record, existing only in a perpetual present. As befits his celebration of music, the speaker's language, sensually rich though it is, serves to suppress the sense of sight in favor of the other senses. In "Nightingale," he has achieved creative expression and has placed his faith in it, but that expression--the nightingale's song--is spontaneous and without physical manifestation. This is an odd poem because it both conforms to and contradicts some of the ideas he expresses elsewhere, notably the famous concept of “Negative Capability,”. This can be taken several ways, but is often linked with the statement he made:
“If a sparrow come before my Window I take part in its existence and pick about the Gravel.”
While Keats’s begins his poem with “a drowsy numbness pains” the poem that follows is anything but numb. But the opening ties in with the words that end the poem: “Fled is that music — Do I wake or sleep?” Life is or may be a dream — a very Shakespearean image — but, dreaming or awake, perception and empathetic participation are rooted in Keats’s own consciousness. It is only in dreaming, Keats says, that we can become conscious of, and merged with, the life around us. Thus, Keats heads towards Negative Capability in the poem. Keats is not as great as Shakespeare but he has the same power of self-absorption, that wonderful sympathy and identification with all things, that “Negative Capability” which he saw as essential to the creation of great poetry and which Shakespeare possessed so abundantly.