Themes are the fundamental and often universal ideas explored in a literary work.

The Radical Intimacy of Romantic Love

One of the poem’s central themes relates to the radical intimacy involved in romantic love. The speaker spotlights this theme most clearly in the opening quatrain (lines 1–4):

     i carry your heart with me(i carry it in
     my heart)i am never without it(anywhere
     i go you go,my dear;and whatever is done
     by only me is your doing,my darling)

The speaker doesn’t merely carry their beloved’s heart with them. As they clarify in the parenthetical statement that spills over the first line break, they carry their beloved’s heart in their own heart. This image of a heart inside another heart indicates something beyond the ordinary intimacy of two lovers. Indeed, the heart inside a heart suggests a radical intimacy that exceeds physical proximity. Some readers may find the intimacy described by the speaker so radical that it verges on codependency. Such a reading, though extreme, may be supported by closely examining the rest of the quatrain. There, the speaker claims they are never without their beloved’s heart, which means they are always together. This constant togetherness seems to result in the distinction between individual lovers becoming blurred. The speaker suggests as much when they indicate a blurring of agency, such that “whatever is done / by only me is your doing.” Even so, the radical intimacy the speaker describes is a highly conventional theme in much love poetry.

The Attractive Power of Mystery

The intimacy the speaker shares with their beloved has something to do with the attractive power of mystery. The speaker introduces this theme in the final lines of the second quatrain (lines 8–9):

     and it’s you are whatever a moon has always meant
     and whatever a sun will always sing is you

The speaker doesn’t simply compare their beloved to the moon and the sun. Instead, they liken their beloved to the mysterious nature of these celestial bodies. The key word here is “whatever.” Whatever it is a moon might mean, its meaning “[is] you.” Similarly, whatever it is a sun might sing, its singing “is you.” Put less obscurely, the speaker seems to be saying that their beloved has an air of mystery about them. This air of mystery is attractive, perhaps because the forces at work in the attraction aren’t completely clear. The speaker complicates this theme of mysterious attraction in the final sestet, where they describe what they call “the deepest secret nobody knows” (line 10). This secret relates, they tell us, to “the wonder that's keeping the stars apart” (line 14). Yet the speaker concludes by implying that the mysterious wonder that keeps the stars apart is also what binds them and their beloved together: “i carry your heart(i carry it in my heart)” (line 15).

The Spirituality of Love

Although “i carry your heart with me” initially seems to be about romantic love, as the poem proceeds, it increasingly frames love as a spiritual matter. The turn toward the spirituality of love occurs most clearly in the last section before the closing line, lines 10–14. There, the speaker’s language grows more esoteric as they reference deep secrets that reside within the essences of things:

     here is the deepest secret nobody knows
     (here is the root of the root and the bud of the bud
     and the sky of the sky of a tree called life;which grows
     higher than soul can hope or mind can hide)
     and this is the wonder that's keeping the stars apart

The main idea expressed in these lines relates to “the deepest secret nobody knows,” which links directly to “the wonder that’s keeping the stars apart.” The speaker is talking about some secret, cosmic force that helps maintain the order of universe. However, the long parenthetical digression that occupies the middle three lines describes how this cosmic force derives its power from the smallest, most intimate level of existence. That is, this force lies in the very essence of things: “the root of the root and the bud of the bud / and the sky of the sky.” What the speaker calls “wonder” should thus be understood as a spiritual property at the heart of all things. Just as wonder keeps the stars apart, it also draws the speaker close to their beloved in a powerful union.