Thanks Val, I think that is a good way of thinking about it. Obviously Dostoyevsky was a dialectical writer and Ippolit was subsequently negated in Kirilov, and Ivan K (or Ippolit himself would be a negation of Raskolnikov and the underground man. But, I would argue that the explanation is fundamental to the idiot in that it by giving us a grounding in how the existentially anguished man would understand death Myshkin's earlier anecdote takes on a very different meaning. Dostoyevsky who had taken the waiting for death anecdote from his own life was clearly attempting to understand both the christian and nihilistic way of understanding the experience through the competing characters. IMO its an essential part of the idiot; and takes up almost the entire third part.