Resuming his reading, Kanai reads that Horen invites Nirmal to Morichjhãpi for a feast where there will be journalists and intellectuals. Finally, Nirmal tells Nilima about what he's been up to. As he expected, she's unenthusiastic. She already knew about the settlers and tells Nirmal not to go back—he could get hurt. Nirmal decides to keep his involvement a secret from his wife. The next day, Nirmal packs a bag to go and tells Nilima he's going out with Horen. He recognizes that this moment is when their relationship began to crumble.
When Nirmal pinpoints this moment as the one that begins to destroy his marriage, it shows that he recognizes that the absence of language and the genuine desire to communication can have dire consequences. Getting intellectuals in particular involved in Morichjhãpi suggests that the settlement recognizes how interesting it is to people like Nirmal. Those people also have the power in government.
The feast is strange; Nirmal sees what he could've been had he not left Kolkata. He recognizes some of his old friends, though they don't recognize him, and Nirmal feels more aware than ever of his regrets. Nirmal refuses to eat like a guest; he merely sits and watches. Finally, he approaches a writer he once knew and modestly explains he's no longer writing and is about to retire from being a schoolteacher.
Though the narration made it clear that Nirmal's health absolutely depended on leaving Kolkata, his regret here suggests that he may even value theory and the influence he could've had over his own life and health. This suggests he may be driven to sacrifice later in the novel in an attempt to make up for leaving Kolkata in the first place.
When Nirmal mentions teaching on Morichjhãpi, the writer notes that the settlers may not be able to stay. Nirmal insists that the settlers couldn't be evicted without bloodshed, but the writer reminds Nirmal that they used to support violent revolution. Nirmal thinks about speaking his mind, but decides he has no right to be self-righteous. He recognizes that Nilima spent her life doing important things while he cannot think of what his life's work even is. Nirmal thinks of all the things he'll never get to say or write, and mentions that Rilke wrote nothing for years before producing the Duino Elegies in a matter of weeks.
Remember that the settlers on Morichjhãpi are extremely poor; given the way the novel has already treated the poor people of the Sundarbans, it's clear that Nirmal's belief that the settlers won't be evicted is idealistic and unrealistic. Exactly because the settlers are poor, they're at a much greater risk of being exploited or taken advantage of, as they have fewer means with which to fight back.