"Bartleby the Scrivener"

I found this story very confusing. Bartleby began as a hard working scrivener and accomplished many tasks. After some time though, he begins to refuse everything that anyone tells him to do, including eating. "...nothing stirred. I paused; then went close up to him; stooped over, and saw that his dim eyes were open; otherwise he seemed profoundly sleeping," (674). Why did he do this to himself? What made him decide not to live any longer? Bartleby must have gone through some kind of change to resort to death. I cannot seem to figure out why though. I also assumed that the other scriveners must have some symbolic meaning behind their work ethics, but I never seemed to be able to justify that while reading the story.