In Heart of Darkness, why do you suppose Conrad uses the story-within-a-story framework?I'm just wondering what might Conrad have been after by having Marlow tell his story to four friends rather than just having him tell the story directly.
This is a great question, and to answer it we need to think very carefully about what Conrad wanted to achieve through his choice of how he told the story. The beginning and the end of the novel, presented by a first narrator who introduces Marlow's tale and concludes on it, are usually referred to as the "frame" of the story, with the inner story falling in between the two "frames". One major effect of Conrad's use of a frame and two narrators is to provoke a chain-like reaction: Marlow's story is told to four listeners, one of whom tells it to the readers, who may react differently as the readers to. Among them are a lawyer, an accountant, the company director, and their profession makes them participants in the imperialist venture, and they serve its interests like the company director and the accountant Marlow meets in Brussels and in Africa. The unnamed first narrator is the only one who takes part imaginatively in Marlow's tale and is changed by it too, as his comment at the end of the story that the Thames leads "into the heart of an immense darkness" indicates. Certainly the first narrator has heard and understood what Marlow is trying to establish - that at the heart of any imperial or colonial endeavour, no matter what "good intentions" supposedly cover it, there lies a "heart of darkness" representing the ability of man to exploit and degrade others, just as Kurtz did. The other listeners, on the contrary, either sleep through Marlow's tale and thus remain unaware and untouched, or do not understand what he is trying to say.
The contrast between Marlow's audience and Marlow's attempt to understand and process his experience underlines the importance of the frame. Although there is a brooding gloom hovering over London, the first narrator uses expressions like "exquisite brilliance" and "unstained light" to describe the end of the day. The optimistic perspective he has of colonialism can be seen to mirror this description of the landscape. This view is of course challenged when Marlow begins his narrative with the statement:
And this also... has been one of the dark places of the earth.
The first narrator's introduction therefore raises central issues about perspectives of colonialism that are developed by Marlow's central narrative: the dark role of the city as a centre of "civilisation", the nature of colonialism and the lastly the individual's capacity to reflect on it and explore their own involvement and attitude towards it.
Thus Conrad uses the framing mechanism to tell this tale to explore the issues surrounding colonialism in a more profound fashion. The audience that Marlow has allows us to see different attitudes towards colonialism, and the first narrator permits us to see how such perspectives can change through the course of hearing the tale, as Marlow talks of the potential dangers of colonialism to us all.