Wanting to research weather records for a newspaper article, Ishmael makes his way to the lighthouse. What he finds there makes Chapter 23 a pivotal point in the narrative. Although the chapter is short, the combination of flashback and finding sets the stage for the climax of the novel.
While at the lighthouse, Ishmael remembers the difficulties he and Hatsue had when they happened to run into each other on the island immediately after the war. His memories trigger action in the present, so Ishmael searches for meaningful information. Although Ishmael came to the lighthouse for information about the weather, he ends up searching for information about the night in question. Ishmael's search leads him to the truth: A freighter threw a wall of water powerful enough to knock a man overboard; that's what happened to Carl. The radiomen who worked that night left the next day, so they know nothing about Carl's death and Kabuo's trial. Revealing this critical information so early moves Snow Falling on Cedars from the realm of just being a courtroom drama. Of course, this information doesn't explain the entire specifics of the evening, but it is enough to provide reasonable doubt. Because the reader knows the truth, the narrative becomes an exploration of the decision-making process. What will Ishmael do with this information?
Ishmael, thrust into a powerful position, now needs to deal with a plethora of emotions: revenge, spite, hate, love, and ambivalence. He has information unknown to anyone else, and he also has just had a miserable reunion with Hatsue in addition to remembering their awkward, first, post-war meeting. To an outsider, the decision is easy: Ishmael should reveal what he knows. But Ishmael isn't an outsider. He was actively involved with Hatsue and then passively involved with Kabuo's trial, and he can now be actively involved again. From Ishmael's point of view, what is right for Kabuo may not be what is right for himself. Ishmael knows the truth, but knowledge without action is equivalent to ignorance.
