The Whitmore facilities office issued Isaiah a gray polo shirt, a ring of keys heavier than his own, and a cart that pulled stubbornly to the left. From seven until eleven, four nights a week, he was invisible in the approved way: he emptied wastebaskets in seminar rooms, wiped whiteboards clean of other people's breakthroughs, and mopped the marble steps of Whitmore Hall while students in evening dress stepped around him on their way to receptions he would never attend.
He did not resent the work the way Theo, his roommate, thought he should. "Man, you solve problem sets for rich kids by day and clean their classrooms by night," Theo said once, sprawled on his bunk with an engineering textbook tented over his face. "There's a word for that, and the word is wrong."
"The word is forty dollars a shift," Isaiah said, "plus they let me use the tutoring center copier."
Theo Ramirez had been assigned to him by a housing computer and had decided within a week that they were brothers. He was from El Paso, studied engineering, laughed loudly at his own jokes, and kept a hot plate hidden under a laundry basket in cheerful violation of the housing code. He also kept Isaiah's secrets without being asked, which was rarer and more valuable than the hot plate.
Under Isaiah's desk sat a milk crate he had brought from Chicago on the train, containing seven notebooks bound in black cloth. They had belonged to Samuel Carter.
His father had filled them over twenty years, in the evenings after grading, in a handwriting that grew smaller as the ideas grew larger. There were no finished theorems in them. There were questions, restated patiently, year after year, from new directions β attempts at doors the journals had declined to open. The last notebook was only half full. Samuel Carter had died of a heart attack on a February morning in Isaiah's junior year of high school, in the kitchen, with his coat half on, on his way to teach other people's children the quadratic formula.
Grace Carter had put the crate in Isaiah's hands at the train station in August. She wore her nurse's scrubs under her coat because she was going straight from the platform to a night shift at County General, and she held his face in both hands the way she had when he was small.
"Your father wrote in those like the world was listening," she said. "Maybe it was. Maybe it just wasn't ready. You don't owe those books anything, Isaiah. You hear me? They're yours. You're not theirs."
"I hear you," he said, and carried them onto the train like something entrusted, which they were.
Now, on cleaning nights, he worked his route in the order he had designed: library annex, tutoring center, seminar wing, and last, whenever the schedule allowed, the mathematics building. He liked the buildings empty. Whitmore by day was a performance of belonging; Whitmore at night was just beautiful old rooms, ticking radiators, and boards still ghosted with the day's thinking, which the eraser never entirely removed. If you stood at an angle to the light, you could read the ghosts.
He read them the way other people read notices on a bulletin board. Most were ordinary: problem sets, office hours, a doodled proof that a coffee cup and a doughnut were the same shape, which in topology they were. But the habit had trained his eye. He could walk into a room and feel, before he could explain, whether the work left on a board was confident or stuck, the way his mother could walk into a hospital room and know before the monitors spoke.
Grace called on Tuesdays and Fridays from the break room, with vending-machine coffee, during the twenty minutes the hospital allowed her.
"Are you eating actual food?" she asked that Friday.
"Theo made rice," Isaiah said, wheeling his cart past darkened offices. "There were vegetables near it."
"Near it is not in it, baby. Are you sleeping?"
"Some."
"Are the classes good? Is that professor β the famous one β is he good?"
Isaiah thought of Harrow's chalk snapping under the underline, of the word IMPOSSIBLE still standing on the top board because the day staff had been told, years ago, never to erase the top board during the first month of term.
"He's clear," Isaiah said. "You always know exactly where you stand."
"That's not the same as good," Grace said, and he could hear her smile. "Your daddy was clear and good. Took more effort. Remember that when you're choosing who to become out there."
After the call he stood a while in the corridor, keys in hand, the building humming around him. Then he pushed his cart toward the mathematics wing, where the last room on his route waited with its lights off and its board full of ghosts, and where β though he would not have said so to anyone, not even Theo β he felt closest to the man who had filled seven notebooks with questions and left the eighth unwritten.