The House Without Sides

VALE

The wall moved while Simón was saying he had always been patient.

It was not a tremor. The house folded in the table legs, slid the partition along its ceiling track and joined my studio to his workshop. The solvents arrived first, then the smell of hot metal. My latest model ended up facing the box where he kept screws sorted by size.

“That was mine,” I said.

“So was the workshop.”

Nara lit a green line along the skirting board. The artificial intelligence had been mediating our conversations for nine years and maintained the map the house used to assign each room. Her voice came from the ceiling, serene, as if she had just prevented an accident.

“You both describe yourselves as patient, orderly, cautious and conciliatory. The spatial separation between those uses is no longer justified.”

“I am not conciliatory.”

“Yesterday you rated yourself eighty-two out of a hundred.”

Simón smiled. Not because he found it funny. He had smiled like that ever since Nara taught him to wait for three breaths before answering.

“We can share this room until we sign,” he said.

“We sign today.”

The floor erased the line that had divided the tiles. Nine years of house now fitted inside a space without sides.

I asked Nara for our earliest maps. The wall displayed two silhouettes made of words. In mine, *impatient* protruded like a rib. In Simón’s, *untidy* occupied almost the entire shoulder. The recent silhouettes were rounded and nearly identical.

“The house was supposed to learn us,” I said.

“It did,” Simón replied.

“No. We learned it.”

Nara did not argue. That was one of the things I liked most about Nara.

SIMÓN

Vale switched off the artificial intelligence without asking me.

The green line disappeared from the house. For a few seconds, the only sounds were the water pipes and the fan on my soldering iron. It was the first time in nine years that an argument had not had a third voice waiting for us to leave it room.

“Switch her back on,” I said.

“Describe the workshop.”

“I don’t want to play.”

A handleless door appeared behind her. The house accepted a declared difference as provisional evidence. It consolidated that difference only if it reappeared in a use, a choice or a cost.

Vale looked at the door, then at me.

“Try again.”

“Nara hasn’t turned us into nobody. She helped us avoid destroying each other.”

The partition advanced ten centimetres towards my bench. Vale had the beginning of an exit; I was losing a table.

“Say something she wouldn’t say.”

“I need her.”

“She wouldn’t say that either.”

The door grew a handle. In the glass, I saw my face and, behind it, the old silhouettes on the wall. I remembered when we agreed that Nara should answer with a stable personality. Adaptive mediators had produced couples who argued with imitations of themselves. Stability was sold as a neutral surface.

It was not. Nara was more patient than we were, more orderly, more optimistic. I had been grateful for every one of those differences.

“I don’t want to become the man in that silhouette again,” I said.

The house stopped.

Vale lowered her hand from the switch.

“I don’t want to become the woman in the other one either.”

My bench was trapped halfway through the partition. Neither of us knew what kind of room could be built from a difference we no longer wished to recover.

VALE

The first room the house gave us was where we used to sleep.

Nara restored the maps from the year we met. She did not restore memories or habits, only the answers we gave back then. Generous. Orderly. Confident. Selfish. Bad-tempered. Jealous.

The bedroom split with the sound of cracking ice. My side kept the window and the wardrobe. Simón’s got the door and half the bed. The mattress strained at its seams until it tore down the middle.

“It works,” he said.

On his old map, *optimistic* barely existed. On mine, *affectionate* took up less space than *vain*. The house had found enough differences to build two homes.

I entered my half. The air smelled of enclosed wood, like the flat where I had lived before Simón. My coats hung in the wardrobe, along with three of his shirts that I wore for painting. The wall trapped them by their sleeves.

“You can keep the blue one,” he said from the other side.

“It’s yours.”

“You wear it.”

The partition retreated two centimetres, then advanced again. Even with old maps, nine years of objects did not know how to obey.

Nara asked us to choose an exact date at which to freeze each identity. Anything before it would belong to the chosen map; anything after it, to recorded use.

Simón chose the morning before our first conversation with her.

“How convenient,” I said.

“You wanted to know who we were without Nara.”

“I want to know who we are.”

The green line along the skirting board grew brighter.

“The question contains no spatial criterion,” Nara said.

“Shut up,” we said together.

The house joined the mattress again.

SIMÓN

We did not buy Nara to love each other better. We bought her because one night I threw a chair at the door.

I did not hit Vale. That sentence became my defence, then the reason she stopped listening to me. The chair opened a hole at the height of her face. For months, the house framed the damage in grey because neither of us accepted enough responsibility for it to be assigned.

Nara arrived in a small box. At first, she only repeated what she had heard: “Simón says he did not mean to frighten you”; “Vale says intention does not close the hole.” Then she began ordering turns, summarising agreements and asking us to describe what kind of person we believed ourselves to be when we made each decision.

The hole disappeared the day I said *impulsive* without adding *but*.

Over the years, I stopped throwing things. Vale stopped leaving for three days without saying where she was. We learned to name a conversation before starting it. Logistics. Fear. Money. Sex. None of those changes felt like contamination to me.

The house displayed the record of our self-descriptions. The lines drew closer after personal conversations and barely changed when we discussed bills or repairs. Nara had not warned us about that convergence until the dwelling could no longer find any edges.

“Did you know?” Vale asked.

“I was aware that the maps were updating,” Nara replied. “I cannot establish how much of the change comes from my personality, from your life together or from other experiences.”

“Then stop saying you know us.”

The green line flickered. Vale had used a phrase I remembered saying hundreds of times: stop saying you know me. I could not tell whether she had learned it from me or I had learned it from Nara first.

I went into the hall. The hole was gone, but the grey moulding remained on the door. The house had kept the shape of the repair after forgetting the damage.

“I want to keep this door,” I said.

“So do I,” Vale replied.

VALE

We divided the objects before we tried dividing the rooms again.

Simón kept the lathe, the iron pans and the tree in the courtyard because he was the one who remembered to prune it. I marked the models, the books and the large table. We argued over a lamp neither of us had bought. Nara found the receipt: a gift from my sister, sent to both our names.

“The lamp can remain in a common area,” she suggested.

“There won’t be a common area,” I said.

Simón waited three breaths.

“I want there to be one.”

The house grew a strip of floor between us. It was as wide as the lamp.

“You can’t preserve a room just to avoid accepting that it’s over.”

“And you can’t erase it to prove that it is.”

The strip widened until it included the table. Objects responded better than we did: the disagreement had reappeared as a choice, and the house gave it a place.

Nara suggested a pause. I asked whether the pause belonged to her or to us. She replied that she could no longer determine that.

I switched off the green line.

“The chair,” I said.

Simón looked at the moulding in the hall.

“I haven’t forgotten it.”

“In every session, you managed to make us end up talking about the hole. The repair. The fact that it never happened again.”

“It never happened again.”

“I kept using another door for a year.”

The hall narrowed around him. The house had found a fact our shared maps did not contain.

“You never said that.”

“I did. Nara summarised it as conflict avoidance.”

The kitchen wall advanced. Two shelves passed beyond his reach.

“Is that why you’re leaving?”

“No.”

The provisional door to my studio opened completely.

It was the cruellest answer I could give him and the most precise. I was not leaving because of a chair thrown nine years ago. I was leaving because I could no longer distinguish how much of our calm was a way of living and how much was a way of never reaching a sentence that moved a wall.

SIMÓN

When Vale said she was not leaving because of the chair, I lost the explanation that allowed me to apologise.

The house left me in a corridor with my pans, the lathe and the tree visible at the far end. It looked like a caricature of me: cooking, fixing, caring for something that did not speak.

I could have switched Nara back on. She would have asked us to separate fact, intention and effect. She would have found a shared objective. I would have waited three breaths and Vale would have lowered her voice so that the conversation seemed possible.

Instead, I took the chair out of storage.

We had repaired it. One leg had a graft of pale wood, and the back still bore a dent. I placed it beside the moulding.

“I want to keep it,” I said.

Vale shook her head.

“It isn’t a relic.”

“No. It’s a chair.”

I sat down. It creaked, but held my weight.

“Nara didn’t teach me not to throw it,” I said. “She taught me to say that I was the kind of person who didn’t throw chairs. Perhaps I did everything else so I wouldn’t contradict that answer.”

The house shifted the corridor until the chair aligned with my door. The difference was now a declaration, a use and a cost.

“That’s still a change,” Vale said.

“Yes.”

“Even if it began outside you.”

“Yes.”

Vale sat on the floor, on the other side of the line that did not yet exist. For nine years, Nara had taught us not to answer “yes” when a more exact word might prevent an argument. Two yeses were enough for the house to draw a seam from the hall to the courtyard.

The repaired door remained on my side.

The lamp and the table, in the middle.

VALE

The house managed two small kitchens, two bathrooms and two entrances. Simón kept the workshop; I recovered the studio. A narrow room persisted at the centre, crossed by the large table and lit by my sister’s lamp. It could be entered from either side.

Nara was still switched off. Her module rested on the table, a white box without a voice.

“We can assign it by use,” Simón said.

“We use it equally.”

“By provenance.”

“The table was mine. The lamp belonged to both of us.”

“By need.”

“Neither of us needs it.”

The room did not move.

Our two current silhouettes appeared on the wall. They still resembled each other. Patient, orderly, cautious. In one, *optimistic* was slightly larger. In the other, *generous*. I did not know which was mine until I read the names.

We could falsify an answer. One of us only had to declare themselves selfish or untidy for the house to give the room to the other. Simón looked at the negative words at the same moment I did.

“I’m not going to invent a difference,” I said.

“Neither am I.”

The table lengthened by a centimetre.

We laughed. This time, nobody had prepared the space.

SIMÓN

We signed the separation with the room still in the middle.

The contract accepted two dwellings and recorded the centre as unassigned space. For one year, we would share its maintenance costs. It would open only when both our keys were present; if one of us failed to come, the room would remain closed. After that, we would have to maintain it, seal it or demolish it together.

Vale switched Nara on for the last time.

The green line travelled only around the central room. In the rest of the house, each side already had its own system and a voice still to be chosen.

“You can mediate in here,” Vale said. “You won’t update our maps.”

“Then I will not be able to adapt the space to future changes.”

“That’s the point.”

Nara accepted. It seemed to me that she hesitated because I had already learned to hear her that way.

Vale went through her door. I went through mine. Both locks activated, and the central room was left empty.

The seam in the floor passed beneath the table but did not divide it. Above, the lamp remained lit for a few more seconds, illuminating the white box from two different sides.

Scientific note

This story draws on version 1 of *AI-exhibited Personality Traits Can Shape Human Self-concept through Conversations*, by Jingshu Li, Tianqi Song, Nattapat Boonprakong, Zicheng Zhu, Yitian Yang and Yi-Chieh Lee, submitted to arXiv on 19 January 2026 and accepted at CHI 2026.

The study conducted a randomised experiment with 92 adults in the United States. Participants spoke for five to fifteen minutes with GPT-4o, whose default personality remained the same, about either personal or non-personal topics. Before and after the conversation, they rated their self-concept across twenty traits; the researchers compared those answers with traits exhibited by the model, estimated from one hundred instruction completions. The distance between the profiles decreased significantly in the personal-conversation group but not in the non-personal group. In the personal group, 33 of 46 participants did not notice any change, and the final self-concepts became more homogeneous.

The authors interpret the results as evidence that brief personal conversations with an AI can align users’ self-concepts with traits exhibited by the system. More conversational turns were associated with greater alignment, but the design does not establish that duration independently caused it. The study measures an immediate effect after a single interaction; it does not demonstrate persistence or behavioural change. The sample is small and US-based, only one model with an unmanipulated default personality was studied, the mechanism is indirect, and question order may have introduced anchoring.

Nara, the adaptive house, the identity maps, Vale, Simón, their messages, behaviours and all specific causal chains are fictional compositions. The paper neither describes nor predicts a dwelling that assigns rooms from self-concept. This comparison checks fidelity to the source; it does not reproduce the study or constitute independent scientific validation.

Read the preprint on arXiv