How are light and darkness used by Joseph Conrad in his novel Heart of Darkness?

[Page
numbers from which quotes are taken are
not available, as the Kindle version of the book was
used.]

s uses light and darkness as metaphors

for mental awakening and for representations of death, evil and emptiness.  The mere
title,
Heart of Darkness, is a reference both to
the metaphorical
darkness that resides inside of man €“ or, more
specifically, in the European colonialists who
systematically enslaved
millions while exploiting their resources €“ and to the image of the
deepest
parts of Africa as dark, both in terms of the literal absence of light beneath
the
heavily-canopied jungles and to the long-discredited notion of Africa as
devoid of culture and
worth (the dark continent).   Early in his novel,
Conrads , Charles , references his travels
down the Congo River into the
heart of Africa, and how the experience of visiting that location
and finally
encountering

seemed somehow to throw
a
kind of...