Thou still unravish’d bride of quietness,
       Thou foster-child of silence and slow time

The speaker opens the poem with these lines, which address the urn through a series of two metaphors. The first metaphor boldly likens the urn to a “still unravish’d bride of quietness.” Note the ambiguity of the word “still.” It isn’t perfectly clear whether this is used as an adjective (i.e., “unmoving”) or an adverb (i.e., “as yet”). If the former, the speaker is emphasizing the urn’s capacity to remain fixed in time. If the latter, the speaker is emphasizing how the urn retains its essential mystery. It’s also worth noting that the phrase “unravish’d bride” is self-contradictory. Marriages are traditionally consummated through sexual union, so the notion of a virgin bride seem contradictory. Yet the speaker’s phrase does make logical sense. The urn is specifically a “bride of quietness,” and since “her” silence has yet to be broken, this bride remains virginal, and hence “unravish’d.” In the second metaphor, the speaker uses a different type of kinship relation to describe the urn as a “foster-child of silence and slow time.” Taken together, these metaphors establish an elaborate opening address to the urn, demonstrating the speaker’s reverence for this artifact that has preserved its mystery through centuries of “slow time.”

Heard melodies are sweet, but those unheard
       Are sweeter; therefore, ye soft pipes, play on;
Not to the sensual ear, but, more endear’d,
       Pipe to the spirit ditties of no tone

In lines 11-14, the speaker reflects on the image of a piper who’s playing a tune. But because the piper is a static image frozen in time, his tune clearly cannot be heard. Even so, the speaker insists that “unheard [melodies] / Are sweeter” than their “heard” counterparts. An unheard melody is not detectable by what the speaker calls “the sensual ear,” which is to say the physical ear that channels sound waves and allows us to tune into the audible world around us. Held in implicit contrast to the sensual ear is what we might call “the spiritual ear,” which is to say the immaterial “ear” of the imagination. This spiritual ear is more attuned—and hence “more endear’d”—to the “spirit ditties of no tone” played by the static piper. Taken together, these paradoxical references to silent music underscore the simultaneous beauty and mystery of art, which requires us to engage both our physical senses and imaginative capacities.

More happy love! more happy, happy love!    
         For ever warm and still to be enjoy’d,
                For ever panting, and for ever young;
All breathing human passion far above,
         That leaves a heart high-sorrowful and cloy’d,
                A burning forehead, and a parching tongue.

In lines 25–30, the speaker responds to an image of young lovers in throes of amorous desire. The speaker has previously described a “fair youth” and a “bold lover” (lines 15 and 17) as being frozen in the moment just before their lips join for a kiss. Though they will be forever young and in love, the speaker acknowledges the frustration implicit in them never getting to consummate their love. In this passage, the speaker takes the same idea further, imagining the physical and emotional turmoil that would come from being perpetually stuck in a moment of sexual arousal. These lovers would be “for ever panting” with “a burning forehead, and a parching tongue.” The exhausting nature of such a condition is enough to turn the excitement of love against itself, “leav[ing] a heart high-sorrowful and cloy’d.” Keats amplifies the feeling of agitation by making powerful use of repetition. The insistent echoes of “happy love” and “more happy, happy love” emphasize the unceasing intensity of the young lovers’ attraction. Likewise, the repetition of the phrase “for ever” underscores the fact that the lovers are frozen in time.

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.

Lines 46–50, which conclude the poem, have developed a reputation among critics for their puzzling ambiguity. At first glance, this ambiguity may not seem obvious. The speaker begins by reflecting on how the immortality of the urn contrasts with their own mortality. When the speaker and their generation are all dead and the world has moved on to experience new forms of “woe,” the urn will remain. The ambiguous bit comes next, when the speaker speculates that the urn, acting a “a friend to man,” might want to communicate a message to humankind. In the version of the poem used for this guide, which is the most common version in modern use, there are quotation marks around the phrase, “Beauty is truth, truth beauty.” This, we presume, is the urn’s message. The words that follow, which are not in quotation marks, again belong to the speaker, who resumes their address to the urn. In this version, the speaker clearly recognizes the simplicity of the urn’s perspective, which, though it may offer naïve consolation, cannot account for the complexity of the human condition.

However, it must be noted that in the original version of the poem, printed in Annals of the Fine Arts in 1819, Keats didn’t include any quotation marks. That edition rendered the final lines as follows:

         Beauty is Truth, Truth Beauty.—That is all
                Ye know on Earth, and all ye need to know.

In the first printed version, the ambiguity of these lines becomes more pronounced, since we can no longer be sure who is speaking at any given point. If the urn only says the maxim, “Beauty is Truth, Truth Beauty,” and the rest is said by the speaker, then we may interpret these lines in the way described above. However, if the urn is responsible for saying everything in these lines, then matters become more complicated. For example, it becomes unclear whether the “ye” in the last line is addressed to the speaker of the poem, to the readers, or perhaps to the figures depicted on the urn. Furthermore, if the urn is the last voice to speak in the poem, it becomes possible to interpret their concluding maxim not as a naïve oversimplification, but as a meaningful and substantial proposition. In that case, we might interpret the equation of truth and beauty as a philosophical principle that transcends the ordinary pain and suffering of human life. These ambiguities have given rise to two centuries of critical debate.

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