Sylvia Plath begins her poem “Fever 103” with a one-word question: “Pure?” as if from the middle of an unheard conversation. She asks impatiently, “What does it mean?” and then plunges in, conjuring up the heat of a high fever:

The tongues of hell
Are dull, dull as the triple

Tongues of dull, fat Cerberus
Who wheezes at the gate. Incapable
Of licking clean

The aguey tendon, the sin, the sin.
The tinder cries.
The indelible smell

Of a snuffed candle!

In a few bold strokes, Plath uses repetition’s incantatory effect to undercut our assumptions about purity. When she writes “tongues of hell,” we think of the shapes of flames and purification by fire. Instead, Plath gives us dog slobber: “dull, dull as the triple // Tongues of dull, fat Cerberus.” Her emphatic twist on the Cerberus myth renders the terrifying three-headed hound of hell into a plainly pathetic old dog who’s “wheezing” and sluggish, “Incapable / Of licking clean // The aguey tendon.” (I must pause here, at “aguey,” to admire how the old-fashioned word onomatopoetically expresses the pulled-taffy feeling of a high fever.)

When Plath repeats “the sin, the sin,” it conjures all kinds, exponentially multiplying sin itself. The repetition amplifies what comes after it. “Sin” morphs sonically into “tinder,” which, with its soft “ind” sound, both recalls “tendon” and prefigures “indelible.” The pleasure of rhyme heightens the dead black fiery-waxy scent and sonic satisfaction of “a snuffed candle.” It also offers a meager sort of exhausted relief after the terror of crying tinder. If Plath is creating the sense of a fever burning away the soul’s impurities, then she is also creating the sense of a soul so completely composed of impurities that this fever threatens to burn it entirely out.

The poem continues:

Love, love, the low smokes roll
From me like Isadora’s scarves, I’m in a fright

One scarf will catch and anchor in the wheel,
Such yellow sullen smokes
Make their own element. They will not rise,

But trundle round the globe

When Plath writes “Love, love, the low smokes roll,” notice how “love” becomes “low” becomes “smokes” becomes “roll”—and how all those round “O” sounds recall and amplify the “ull’s” and “ell’s” in the preceding stanzas, embodying the smoke and giving it weight. Instead of a puff of smoke—or smoke as anything insubstantial and easily waved away—here smoke is deadly and heavy, originating and emanating from herself. It “will not rise” and dissipate. It menaces and threatens the entire planet,

Choking the aged and the meek,
The weak

Hothouse baby in its crib,
The ghastly orchid
Hanging its hanging garden in the air.

The imagery here is lacerating. With an effortless transposition of adjectives, (“hothouse” for baby and “ghastly” for orchid), Plath nails the sweaty, sleepless (and verboten) repulsion that this new mother feels for her infant: How horrible babies are! And beautiful! The nightmarish imagery morphs: smoke to scarf to knot to noose, infant to orchid to a jungly overgrown garden. The poem is a fever-smear, a dreamy nightmare, fully infecting us—half by image and half by sound.

By the flash-light of her fevered vision, Plath leads us into an apocalyptic wasteland. Then, like a hypnotist, she brings us back from it by repeating the words that induced the state. When she reprises “The sin. The sin,” the phrase beats twice on a muffled drum. It’s an almost-ending; after the transmogrifications of fever, we return (for a second) to the regular world. We pause, take a breath, and—begin again:

Darling, all night
I have been flickering, off, on, off, on.

In this “flickering,” we see faint flashes of dim light and we hear tiny electrical noises. We take a gulp of ordinary air—before the next line sucks us right back down into the delirium-dream, where fabric becomes flesh, and “The sheets grow heavy as a lecher’s kiss.” Plath’s tone is fussy, irritable, sick of being sick:

Three days. Three nights.
Lemon water, chicken
Water, water make me retch.

Plath is loud now, and large, unconfused by delirium. “I am too pure for you or anyone,” she says, referring back to the poem’s first question. She is now the master of her feverish animal, all-powerful and entirely autonomous, self-made, and self-regenerating: She is a light-source (“I am a lantern”) and a planet (“My head a moon / Of”—paper covers rock!—“Of Japanese paper.”) The poem builds to an elated sense of momentum here, achieved through the repetitive effect of these declarations of self. This piling-up of insistent “I am’s” continues with an almost childlike sense of amazed accomplishment, declaring, “All by myself I am a huge camellia.”

Without any help, she’s made herself into a flower—a flower with a face, pulsing with light: “Glowing and coming and going, flush on flush.” At this point Plath pushes up and past her own immense illuminated image, giving us the sense of an actual, wobbly lift-off:

I think I am going up,
I think I may rise——
The beads of hot metal fly, and I love, I

Solid becomes liquid and liquid becomes gas. The I-sound in “fly” compounds the I-sound in “rise”—and “I love, I” (I love myself!!!).

Am a pure acetylene
Virgin.

By the poem’s finish, Plath is the self-made Virgin Herself—made of acetylene, no less—a colorless, flammable gas capable (unlike slobbery Cerberus) of cutting through even metal. She is “attended” (like a queen, like an invalid) not by nurses or subjects or servants, but “by roses, // By kisses, by cherubim, / By whatever these pink things mean!” Fever spots? Freckles? Flowers? Angels? It doesn’t matter.

Here, in the poem’s last five lines, the fever’s laser-point becomes a spray. The knife-blade doesn’t dull, but begins to disintegrate. Those “pink things” might mean anything except the other: “Not you, nor him // Nor him, nor him”—lines that resurrect, echo, and link “him” to “The sin. The sin.” One by one, she numbers her discarded “selves dissolving, old whore petticoats.” She is ascending whole to heaven now — freed from the constraints of gravity and identity, the fires of her own creative momentum incinerating any last tether she has to the earth.

The poem’s last word, the capital-P “Paradise,” is almost as abstract in meaning as the poem’s first word, “Pure.” In this way, Plath pairs the two and leads us on a passage from one to the other, connecting the dots. But does “purity” lead to “paradise”? The structure of the poem seems to suggest that, but we cannot help but suspect that at this point Plath’s tone is ironic—the stock image of the Virgin ascending to heaven cannot help but look overwrought.

She is almost out of sight, almost out of earshot—and then, in the very last line, even the sound-play disintegrates. The sound of “paradise” first faintly recalls and then quickly forgets its rhyme-relation to the words “fly” and “rise,” which came on so strongly a now-distant ten lines before it. This effect is more than powerful—it sounds like what it says: it demonstrates a dissolve. Plath does not finish the poem by solving it, but dis-solves it—the poem, herself, the concept of “sin,” the construct of identity, the question of purity. Though she may have asked what purity means at the beginning of the poem, in the end she’s freed herself from the restriction of a definitive answer. Her fever is a fire that feeds itself—a self-fulfilling, self-sustaining, more than slightly frightening metaphor for her own generative genius—one kind of pure paradise.