Piya wakes up around midnight and goes on deck, where she finds Kanai still reading. She sits with him and asks about the notebook, inspecting the tiny Bengali writing. Kanai explains that it's partially about Fokir and Kusum, whom he believes Nirmal was in love with—though he'd never admit it. Kanai explains that Nirmal was a Marxist radical, and Nilima believes that Nirmal involved himself on Morichjhãpi because he couldn't let go of the idea of revolution. Kanai says that he believes that Nirmal just lived through poetry, and took Rainer Maria Rilke's words that "life is lived in transformation" to heart. Kanai believes that Nirmal saw that transformation embodied in Kusum.
Kanai essentially suggests that Kusum was Nirmal's muse in much the same way that Piya is becoming Kanai's muse: to the men, both women represent an ideal and a drive that they've lost in their own lives. The assertion that Nirmal was so caught up in the idea of life being lived in transformation adds some explanation to his life of inaction, as it suggests that he may have believed on some level that he was acting—just in a slower, more day-to-day manner than the life Kusum led.
Kanai says that Nirmal was a historical materialist, which he defines as a belief that everything is interconnected and can then become stories. As an example, he tells the story of Canning, the city on the Matla River. Lord Canning decided that Bengal needed a new port city, and his planners decided on the banks of the Matla river. "Matla" means "mad" in Bangali, but the Englishmen took no notice of the river's apt name. They began work on the city.
It's worth noting that Lord Canning and his planners ignored an Indian name for a river, which illustrates how different languages are given priority—even when the message in one language may be more important than the other language gives it credit for.
In Kolkata at the time, however, there was a shipping inspector named Henry Piddington. He'd fallen in love with storms while in the Caribbean, and he understood that the Matla river was truly mad. Piddington wrote letters to everyone he could, telling them that a city so far out in tide country would be dangerously exposed to cyclones, waves, and tidal surges. He even staked his reputation on his belief that a cyclone would flatten the city within fifteen years. Nobody listened, and people sniggered behind Piddington's back and called him crazy. The river, however, only made Piddington wait five years before proving him right and flattening the city with a tidal surge. Kanai said that Nirmal always closed with a Rilke quote, using it to compare Canning to "a post office on Sunday."
By comparing Canning to a post office on Sunday, Nirmal acknowledges that Canning was a great idea, but the particulars of the city made it something wholly worthless—just as a post office on Sunday is worthless if one wants to send or receive mail. Henry Piddington himself illustrates that it's not just locals that can feel an intense connection to the natural world, and it's not just poor Indian people who aren't afforded a listening ear. When nobody listens to him, it suggests that the hierarchy itself harms many people.