His high school friend Aka was very bright too, with a practical, even utilitarian intelligence. Compared to Aka’s, Haida’s intelligence was more pure iteration, more theoretical, even self-contained. When they were together Tsukuru often couldn’t grasp what Haida might be thinking. Something in Haida’s brain surged forward, outpacing Tsukuru, but what sort of thing that something was, he couldn’t say. When that happened he felt confused and left behind, alone. But he never felt anxiety or irritation toward his younger friend. Haida’s mind was just too quick, his sphere of mental activity too broad, on a different level entirely. With this knowledge, Tsukuru ceased trying to keep up with Haida.

In Haida’s brain there must have been a kind of high-speed circuit built to match the pace of his thoughts, requiring him to occasionally engage his gears, to let his mind race for fixed periods of time. If he didn’t—if he kept on running in low gear to keep pace with Tsukuru’s reduced speed—Haida’s mental infrastructure would overheat and start to malfunction. Or at least, Tsukuru got that impression. After a while Haida would debark from this circuit and, as if nothing had happened, smile calmly and return to the place where Tsukuru lay waiting. He’d slow down, and keep pace with Tsukuru’s mind.

How long did Haida’s intense gaze continue? Tsukuru could no longer judge the length of time. Haida stood there, unmoving, in the middle of the night, staring wordlessly at him. Haida seemed to have something he wanted to say, a message he needed to convey, but for some reason he couldn’t translate that message into words. And this made Tsukuru’s younger, intelligent friend unusually irritated.

As he lay in bed, Tsukuru recalled Haida’s story about Midorikawa. Before Midorikawa had played the piano in the junior-high music room, he’d laid a small bag on top of the piano. He’d been on the verge of death—or so he’d said. What was in the bag? Haida’s story had ended before he revealed the contents. Tsukuru was intensely curious about what had been inside, and wanted someone to tell him its significance. Why did Midorikawa so carefully place that bag on top of the piano? This had to be the missing key to the story.

But he wasn’t given the answer. After a long silence Haida—or Haida’s alter ego—quietly left. At the very end of his visit, Tsukuru felt like he caught the sound of Haida’s light breathing, but he couldn’t be sure. Like incense smoke swallowed up in the air, Haida’s presence faded and vanished, and before Tsukuru knew it, he was alone again in the dark room. He still couldn’t move his body. The cable between his will and his muscles remained disconnected, the bolt that linked them together having fallen off.