A. You will make sure

She made sure that his pencils were sharpened and that his books were arranged on the shelf by subject. Her limp grew more pronounced. She ordered his papers in neat, parallel stacks, and made sure that there was always fresh ink in the inkstand. There was never any dust. Every morning she organized notes from the day before, scraps covered in neat script and schematics and question marks, but she did not look at them. It had been too long since the medicine courses and then her increasing interest in mathematics, in differential calculus, in projective geometry, in physics. Him and then the child, a girl, and then the others—and Bern and Zurich and Prague and Zurich again and now Berlin—and she was tired. Their apartment was large and dark and she spent much of her time asleep. Electromagnetic fields thrummed through her dreams.

1. that my clothes and laundry are kept in good order;

The linen snapped on the line strung across the balcony. Beyond it, the February sky was a flaccid grey. A pigeon strutted and cooed and she watched as it flew away.

2. that I will receive my three meals regularly in my room;

His teaching salary meant they had enough money for a maid of all work now, but she still had to cook breakfast and lunch. She brought the meals to him on a tray and then returned to the kitchen. Sitting at the table and looking out onto the colorless city, she drank tea out of her favorite china cup, the one covered with hand-painted violets and thin enough to chatter against her teeth. The plainness of his food troubled her—she, who had grown up on consommé and meat pie, trout poached with lemon and sorrel and rosemary, roasted game birds stuffed with sauerkraut and grapes, and wine that reminded her of spring in Zagreb: new grass and limestone and plum blossoms. And the butter! Butter merging with the ribbons of fat in ham hocks, butter pooling into the corners of the fish dish, butter gathering under her fingernails and dripping down her chin. He ate spaghetti. He drank milk. He did not like butter.

3. that my bedroom and study are kept neat, and especially that my desk is left for my use only.

The smell of him overwhelmed her when she walked into his room. She pulled open the curtains, lifting the sash to let in the cold air of the April afternoon. The maid, Famke, had quit. She hadn’t yet hired a replacement. Today it was her duty to empty his bedpan.

B. You will renounce all personal relations with me insofar as they are not completely necessary for social reasons. Specifically, you will forgo

She feels the tidal pull of a future without him. She has almost forgotten what life was like, all those years ago, when they’d talked over books and equations, she his little witch. Density of matter, radiation, heat conduction experiments with Bunsen burners. This knowledge had flared inside of her; it had fit into all her corners. Now it is only silence, boiled potatoes, the festering grief for the dead child, and his letters to Elsa, which have been increasingly frequent since they came to Berlin. Now rage coagulates inside of her, a pulsing phosphorescent mass. She is bottomless but tries to find the bottom anyway. She drinks wine and schnapps and wipes her mouth off with the back of her hand. They have not laughed together since they’d sat under the oak tree with Marie last summer, fingers sticky with marzipan from the picnic basket, the children’s faces empurpled with blackberries they’d picked. Even little Eduard, who could be an inconstant and demanding child, had smiled and ran with the others as the afternoon melted into dusk.

1. my sitting at home with you;

At school she’d grown used to being alone. Often the only woman in rooms of men, libraries of men, offices of men—there were so many men, populating this planet!—she ate alone and studied alone. But the work made sense to her, the way the numbers cataloged the strangeness of the world and gave it a purpose. When she’d discovered mathematics she’d understood how life could be better; when she’d discovered physics she’d understood how she could be better. The principles that organized the universe dissolved her: these tautly rotating planets, these trembling waves of light.

2. my going out or travelling with you.

They went walking in Grunewald Forest on a Tuesday in late May, the first warm day of the year, her and Hans and Eduard and Emilia, the new maid. Hans and Eduard ran up the path in front of them, hitting the cornflowers with fallen branches until the air filled with blue petals. She scolded them but Emilia was laughing. The smell of the vegetation was thick, oversaturated, and the sky was a fastidious blue, powdery clouds suspended as though motionless within it. They stopped and spread a blanket and ate herring bought from a stand and lebkuchen made at home. The trees marbled the sunlight and she laid down and felt the grass poking through the layers of fabric and into her back. Eduard screamed at Hans and she closed her eyes. She could feel her very atoms shifting and vibrating in the heat. Gentled into a state of contentment, she sat up and hugged Hans and Eduard to her. Eduard put his small sticky hands in hers and they sat that way for a long moment before the boys were up and running again. She and Emilia talked of inconsequential things. Then she got up and ran after them, laughing.

C. You will obey the following points in your relations with me:
Her ring sits on her finger, flesh warmed and glinting. It is thinner now. In eleven years its golden particles have become untethered from their temporary structure: a constant slow departure. As she sits alone in the darkened apartment, she pictures the molecules in the air around her push against each other. She can almost feel them against her cheek as they quiver and dance.

1. you will not expect any intimacy from me, nor will you reproach me in any way;

She stops tying her ribbon around her throat the way he used to like. The smooth slip of the silk against her skin, the green of it compared with the green of her eyes, have become an irritation, an itch she cannot scratch. Without the ribbon and with her corset on but the laces loose, she is almost comfortable.

2. you will stop talking to me if I request it;

By July, Emilia is gone. Dust fills the apartment and the milk has curdled. Everything she wanted for herself she pours into the children. If you put energy into an object, then you do work on that object (mass). If a first object is the agent that gives energy to a second object, then the first object does work on the second object. This is a transfer of energy. Even though he is only four, she can already sense that Eduard will need care to navigate through the complexities of a life; he is brilliant, like his father, but fickle and incendiary. She’s never sure what will make him burn. His moods wax and wane. She buys more milk.

3. you will leave my bedroom or study immediately without protest if I request it.

She was twenty-five the first time they’d been together. Later, when she left school to hide her condition, she still didn’t regret it. Their daughter, Lieserl, had died of scarlet fever. They’d married, and Hans and Eduard had come. She’d given the rest up, the teaching and the calculus and the physics, for him, or for the children; she can no longer remember which.

D. You will undertake not to belittle me in front of our children, either through words or behaviour

The sound of him eating an apple fills the apartment. She will leave soon.