“Mirror” has a two-part structure that’s evident in the poem’s formal division into two nine-line stanzas. These two stanzas, identical in length, mirror one another across the break in the middle of the poem. In this regard, then, “Mirror” visually manifests the concept of reflection announced in the poem’s title. The two halves of the poem also mirror each other in terms of content. Not only do they both reveal the shortcomings of objectivity, but they also demonstrate how reflection is never a simple, surface-level phenomenon. In the first stanza, the speaker is a mirror that insists on their lack of preconceptions. They also insist that they’re truthful rather than cruel in the way they reflect the world, “unmisted by love or dislike” (line 3). Yet the mirror subtly undermines their claim to objectivity in lines 6–9:

     Most of the time I meditate on the opposite wall.
     It is pink, with speckles. I have looked at it so long
     I think it is part of my heart. But it flickers.
     Faces and darkness separate us over and over.

Here, the mirror describes how they “meditate on” the speckled wall directly across from them. The use of the word meditate suggests a deeper kind of reflection than we might expect from a mirror, implying a dimension of depth beyond the silver surface. The mirror affirms this sense of depth when they indicate that the speckled wall “is part of [their] heart.”

The second stanza mirrors the themes of the first and develops them further. In this stanza, the speaker is a lake that gets visited every day by an aging woman who is “searching [the lake’s] reaches for what she really is” (line 11). This woman makes daily pilgrimages to the lake, which in turn helps facilitate her sense of identity. In this way, the lake becomes “important to her” (line 15). Yet the woman is also important to the lake. The speaker reveals as much in the flash of aggression that emerges when the woman seeks solace in sources other than the lake: “Then she turns to those liars, the candles or the moon” (line 12). There’s a hint of jealousy here. Likewise, there’s a hint of affection when the lake says the woman “rewards [them] with tears and an agitation of hands” (line 14). Although the lake reflects the image of the woman “faithfully” (line 13), it’s clear that this reflection isn’t emotionally neutral. Indeed, the word faithfully connotes loyalty in addition to objectivity. This loyalty leads to anxiety as the old woman ages, causing her reflection to transform into an image that increasingly approximates “a terrible fish” (line 18).