Mrs. Park does not sit down. She stands in the consultation room and shifts her weight from foot to foot, and I do not ask her to sit because this is what she does. She moves.
"The corridor," I say. "Between relays one and four."
"The right length," she says. Not long. Not short. The right length.
"Twenty-three meters. I counted once. You could walk it in forty seconds if you went slowly. Not fast enough to sweat. Not slow enough to feel like standing still."
She walked it every day in winter when the park was icy. The corridor was flat, warm, no wind. She timed it once and never again. What would be the point? It was always the same corridor.
After she leaves I sit with three interviews on the table.
Geum-hee measured the corridor in function: laundry dried there, bags hung on relay housings, the hum disappeared after a week. Il-bong measured it in oversight — or its absence. His daughter did homework where nobody checked on her. Mrs. Park measured it in dimension: twenty-three meters, forty seconds, flat, warm.
And Chae-Gyeol, who sent her testimony in eleven handwritten photographs, gave the corridor a name that is not a name: the long part. Language that maps space through use, not planning.
Four people. Four units of measurement. None of them clinical.
I take out a separate sheet and write at the top: Vernacular Index.
Geum-hee, 2031-2038. Unit: function. "We dried laundry there." Il-bong, 2029-2037. Unit: oversight absence. "Nobody checked on her there." Mrs. Park, 2030-2039. Unit: dimension. "The right length." Chae-Gyeol, 2033-2041. Unit: spatial identity. "The long part."
The Vernacular Index is not clinical data. It is not fidelity metrics. It is not Dr. Shin's lux readings, which Gyeol-ri has printed in clean Nanum Gothic and hung on the corridor walls where laundry used to be. It is the language people used for a space before anyone told them it was significant.
Dr. Shin measured the corridor and found acoustic properties. I measured it and found therapeutic properties. Bok found witness properties. Gyeol-ri found art properties. Every one of us found what we went looking for.
Geum-hee found laundry.
Mrs. Park's forty seconds and Dr. Shin's 0.74-second RT60 at 500 Hz describe the same corridor. They do not describe the same place.
I will include the Vernacular Index in the study as a primary document. Not supplementary material. Not anecdotal color.
Director Yun will ask why. The peer reviewers will note that four interviews is not a representative sample. I will say: the corridor's own language, spoken by the people who lived in it before it learned to speak about itself, is the only record of the space that was made before we changed it.
Everything else — my protocols, Bok's witness log, Gyeol-ri's installation, Dr. Shin's measurements — describes the corridor after. The Vernacular Index describes the corridor before.
It is not data. It is the site.
Three interviews done. Four more scheduled. Each one will add a row — another way someone knew this corridor before we arrived with our instruments and our attention and our belief that noticing something changes it.
We were right about that. Noticing changed it. The Vernacular Index is the last record of what it was before we noticed.