It was Eid al-Adha, the Feast of Sacrifice, so the bazaars in Istanbul were closed. We walked along the silent streets, wondering how thirteen million city dwellers could go so quiet and how we were going to spend our leftover lira before our departing flights in a few hours. Toward the Galata Bridge, we found a commotion of doves and pigeons by the Yeni Cami.

Birds of a feather do flock together: leading from Eminönü Square was an avenue lined with animal stalls. A menagerie of birds—cranes, ducks, fancy chickens, peacocks, and pheasants—called from their cages. In other wire cages, puppies, kittens, and rabbits formed furry masses. Another set of aquatic stalls had turtle hatchlings and goldfish. Bags full of seed, dry food, and wood shavings spilled into one another—supplies for every sort of pet.

We stopped before a collection of three-gallon drums. “Prof. Dr. Sülük,” read placards at the top of all the drums, each of which was two-thirds full of cerulean-tinted water. A man stood beside the drums, resting his weight on one of them, shifting his baseball cap with the other hand, gray hair falling from underneath.

“I saw a Man before me unawares: / The oldest man he seemed that ever wore grey hairs.” This was not the Lake District, but in this busy market I thought of William Wordsworth’s “Resolution and Independence.” Facing these tiny barrels of leeches and their keeper, all I could think of was the Romantic’s leech gatherer.

Several hundred leeches writhed. They gathered like a black belt round the middle of each container, near the water’s surface. A few ambitious leeches left the waistband, inching their way toward the lid; a few fell from those curving heights to the bottom of the barrels.

“Prof. Dr. Sülük,” it said at the top of every placard, and beneath those bold headings were lists of ailments of almost every sort: from migraines to fungus, eczema, rheumatism, and even cellulite. The leeches, then, were medicinal.

Hirudo medicinalis were in high demand in Ancient Greece, when bloodletting and the balancing of bodily humors were medical mainstays. Even Hippocrates and Galen wrote approvingly of leeches, which can remove ten times their own weight in blood at every feeding. Although leeches fell from medical favor in the eighteenth century, their occasional use continues, and has even made a comeback in the last few decades. The number of leech sellers on this single street in Istanbul suggests that the market for these wriggling worms is booming.

The bountiful leech markets in Istanbul shocked me; in Wordsworth’s poem, the leech gatherer is already an anachronistic figure. He barely emerges from the landscape: like a rock, his “body was bent double, feet and head / Coming together in life’s pilgrimage.”

The core of “Resolution and Independence” is a conversation between the poet and the leech gatherer, its frame only bringing the man into view and then articulating his effect on the aimless, despondent poet.

The poet speaks first, announcing: “This morning gives us promise of a glorious day.” The leech gatherer’s “courteous speech” is not recorded, only reported, though the poet’s continued inquisition comes as direct speech: “What occupation do you there pursue? / This is a lonesome place for one like you.”

“His words came feebly,” the poet claims, and so to spare readers their feebleness, he continues paraphrasing rather than recording the man’s speech: “To these waters he had come / To gather Leeches, being old and poor: / Employment hazardous and wearisome!”

As if the answer had not already been given, or the nature of the man’s profession was not evident, the poet persists, asking again: “How is it that you live, and what is it you do?”

Not fatigued and ever willing to engage the young poet, the leech gatherer “with a smile did then his words repeat; / And said that, gathering Leeches, far and wide / He travelled.”

The poet, whose sad wanderings are saddened by doubts over his profession, is transfixed by the leech gatherer. Confusion and then pity influence his questions and his appraisal of the man. “The Old-man’s shape, and speech, all troubled me,” the poet confesses. “In my mind’s eye I seemed to see him pace / About the weary moors continually / Wandering about alone and silently.”

Yet whatever pity the poet has mustered is conflated by the man’s “stately speech.” The poem’s titular “Resolution and Independence” are created by the poet’s encounter with the leech gatherer, whose own solitude and resolve inspire him.

“I could have laughed myself to scorn to find / In that decrepit Man so firm a mind,” the poet says, then in a prayer of determination: “‘God,’ said I, ‘be my help and stay secure; /I’ll think of the Leech-gatherer on the lonely moor!’”

It was weeks before I went looking for Wordsworth’s poem, its interlocutors chattering misremembered speech in my mind until I tracked down the actual text.

I feel chastened by the poem when finally I found it. Wordsworth not only observed his leech gatherer, but conversed with him; my leech gatherer had wandered away before I could ask him about his occupation or the ways of the world. Rightfully discerning that I had no intention of buying any of his bloodsuckers, he walked off to another stall to make conversation with another leech gatherer.

It’s hard when staring at parasites not to feel like one yourself, whether you are looking at leeches or reading about leech gatherers. But another read of Wordsworth’s masterpiece reassured me that there’s no shame in a borrowed epiphany. Even Wordsworth was borrowing from the leech gatherer, making “Resolution and Independence” from his own version of the man’s speech, not the speech itself.

There is, as the poet says, always the “mind’s eye,” and there I not only see my ball-capped leech gatherer and his leeches, but hear him speaking, sometimes even the speech of Wordsworth’s poem. There might even be something less abusive in that, the secondhand appropriation of a person rather than a fresh act of appropriating.