The only reason given in the text for the Indian man to kill himself in Hemingway's short story "Indian Camp" is because, as the doctor puts it, the man "couldn't stand things." Because of a leg injury he is bedridden while his wife lies below him in labor, ready to have a baby. The labor is troubled and that's why Dr. Adams is there. Hemingway often left important details out of his stories, so the reader is not sure why the doctor has showed up at the Indian shanty without his medical bag. This is important because the woman is in tremendous pain and has been screaming for quite awhile. Several of the men from the camp have retreated out of range of the woman's screams. Unfortunately, the Indian father is apparently not able to join them because of his injury. Adams has no way to stop the screaming because he has no anesthetic and even comments that the screams are unimportant to his work. They do, however, seem to be important to the Indian man as the screams apparently cause him to slit his throat.
Because of Hemingway's theory of omission, critics have not been satisfied with this simple explanation. Hemingway once wrote:
You could omit anything if you knew that you omitted and the omitted part would strengthen the story and make people feel more than they understood.
Two interesting theories as to why the Indian killed himself have arisen in light of Hemingway's confession that he often left the reader ignorant of important details. In a careful reading of the text, some critics have deduced that Uncle George, who appears to be an unimportant character in the story, may have actually been the father of the woman's baby. Knowing this may have caused the Indian man to kill himself just as the son is brought into the world. Two clues hint at this. First, the woman bites Uncle George as he attempts to hold her down. He replies by saying, "Damn squaw bitch." Later, Uncle George is nowhere to be found when Dr. Adams and Nick are about to leave. Some have suggested that he may be off raping another Indian woman at the camp. These small details have created quite an interesting alternate plot which Hemingway never overtly alludes to in the story. This interpretation seems a bit stretched. It begs the question as to why the Indian would have killed himself instead of going after Uncle George and killing him.
Another theory is posited by Jeffrey Meyers in his essay, "Hemingway's Primitivism and 'Indian Camp.'" Meyers argues that Hemingway was a student of Native American culture (Hemingway had several books on the subject) and that the death is a cultural response as the Indian believes he has lost dignity in having an outside entity interfere with the sacredness of the Indian birth. Meyers writes,
The husband cannot bear this defilement of his wife's purity, which is far worse than her screams.
While this theory seems quite plausible, it seems to ignore Hemingway's intent in the story, which is not to dwell on Native American traditions, but rather to tell a simple coming-of-age story in which the young Nick Adams witnesses both life and death in the short trip to the Indian camp with his father.