the Heart of Darkness's symbols: dream vs reality

In Marlow's narrative, he paints a picture of the Africans that crew the steam boat as scary, mob-like cannibals. In reality we know from a modern perspective that the African crew can function as a literary symbol that represents the picturesque practice of restraint. After being virtually enslaved, subjugated, beaten, and starved, the Africans that crew Marlow's steam boat are able to restrain themselves from mutinying. From Marlow's point of view, we see that the sequence of events can appear to be much more dream-like than the reality of them. So from Marlow's dream-like perception the Africans represent fear and looming danger. The clash between the dream interpretation of the African crew and the reality based interpretation of the African crew are a great example for a psychoanalytical assessment of Heart of Darkness because of the large gap between what Marlow sees, which could be considered the id, and what the reader sees, which is considered the ego.