Marlow entered Stein's house late in the evening and was struck immediately by the dramatic figure of the old man, sitting at his desk, washed in the glow of a single spot of light in the darkened room. Then Marlow's eyes caught the outlines of the cases containing Stein's hobbies. He was surrounded by catacombs of beetles and long glass cases of butterflies. "Marvelous," Stein whispered over one of the cases of butterflies.
Marlow admired one butterfly in particular, and Stein told him that a butterfly was a masterpiece of nature. In comparison, man was amazing, but he was no masterpiece. Then Stein told Marlow how he had acquired this particular specimen.
One day while on the outpost where he lived for so many years, he was called away to a meeting. The summons was fraudulent, however, and Stein encountered an ambush. But he feigned death and was able to kill three soldiers and drive off the others. He looked at one of the men whom he had killed, and suddenly, a shadow seemed to pass over the dead man's forehead. It was this very butterfly, a particularly rare variety that he had dreamed of and searched for all his life. Suddenly, here it was, fluttering slowly away from the corpse of a man who had tried to murder him. Acting just as instantly as he had during the ambush attempt, he clapped his hat over the butterfly.
Immediately, Stein was so stunned by his good fortune that his knees collapsed under him. Life had reached its climax for him at that moment. Stein wanted nothing more. He had been victorious against his enemies, he had a beloved wife and daughter, and now he had the butterfly of his dreams.
Marlow told Stein that he had come to him to discuss another kind of rare specimen — a rare specimen of a man. Then he began describing Jim's unusual nature. Stein murmured that he understood Jim well: Jim was a romantic. Marlow accepted the diagnosis immediately. But what was to be done to cure him? he asked Stein. Stein answered that it was futile to try and "cure" a romantic. Instead, one should focus on helping him to understand how to live with his romanticism — that is, "how to live. . . . How to be. Ach! How to be."
A man, he said, is born and it is as though he has fallen into a sea, a dream. And if he tries to crawl out of his dream, he drowns. To triumph in this sea of dreams, he must immerse himself in the destructive element and battle it into submission in his own individual way. "Reality" is only a dream; we should treat it with great seriousness, and yet we should hold ourselves at a distance from it, knowing that none of it matters ultimately. Thus, we are prevented from "taking matters too much to heart."
Jim's problem, Stein said, was taking matters "too much to heart." He proposed that, for the present, he and Marlow should retire. In the morning, they would speak of "practical" solutions to Jim's problem. They would not try to cure Jim of his romanticism; instead, they would search for ways that they could give Jim a chance to live successfully with his romanticism.
Marlow begins Chapter 21 by explaining where the settlement of Patusan is. It is a little-known post in the Malay Islands, forty miles inland and upriver, controlled by three warring factions. It is known to very few people in the mercantile world.
Two years after Jim accepted Stein's offer of resident manager of the trading post, Marlow went to visit him in Patusan, and he marveled at the change that had been wrought in the young man. Clearly, Jim had accomplished much and had regulated much in Patusan. Marlow, of course, was filled with happiness. Jim's victory over his self-punishing romanticism had been an excellent triumph.
And it was a victory, Marlow says, "in which I had taken my part." Jim had achieved greatness. In fact, he had achieved such greatness that most of those who heard about it could never fathom it because their imaginations were too starved and too dull.
Comparing Jim, who was once so flawed as to seem suicidal, with the masses of other men, Marlow says that Jim was like a "light of glamour created in the shock of trifles, as amazing as the glow of sparks struck from a cold stone — and as short-lived, alas!"
In Chapter 19, Marlow had decided to take Jim's problems to a wealthy merchant named Stein, a respected and trustworthy man. Stein was also a world-renowned collector of rare butterflies and beetles. Marlow (Conrad) now offers us a history (or background) to Mr. Stein.
The main point of this digression is to show us Stein's reaction to treachery, ambush, and betrayal as opposed to the capture of the most beautiful butterfly in the world. In other words, Stein thinks nothing of being betrayed, ambushed, and shot at by would-be assassins (or even deceptively killing some of his would-be assassins), but when, in the next moment, he finds one of the rarest butterflies in the world, his knees collapse with wonderment and joy. Therefore, this digression shows Stein to be probably one of the most magnificent romantics in the world, and thus, he will recognize immediately that Jim is also a romantic. Indeed, after hearing Jim's story, Stein immediately pronounces: "He is romantic — romantic."
Clearly, Stein identifies with Jim and thinks of how many wonderful opportunities have come his way that he has missed while Jim has missed only one — the chance to be the hero of the Patna episode instead of its scapegoat. Stein then suggests to Marlow that their problem is not how to cure Jim, but instead, how to teach him to live (practically and otherwise) with himself.
Chapter 21 introduces us to Patusan, where it is decided that Jim will be sent to replace the present, dishonest manager. The importance of Patusan is that it is the most isolated place in that part of the world. Consequently, it will allow Jim to be extremely isolated and so preoccupied that he will not have time to confront himself with massive attacks of guilt and self-recrimination.
At the end of this chapter, we gain somewhat of an understanding of why Marlow has taken such pains with Jim: Marlow believes that "We exist only in so far as we hang together," and since Jim is one of us, it becomes necessary for Marlow and Stein (and, previously, the others — Mr. Denver, Egstrom, and De Jongh) to look after Jim.