Conrad is noted for his critique of African colonialism; locate some textual excerpts from Heart of Darkness which still show his embeddedness with colonial causes or ideals.

Joseph Conrad is highly critical of individual characters and behaviors that he presents in the novel, and Marlow is ultimately repelled and disgusted by Kurtz when he finally finds him. Heart of Darkness is not ultimately a reformist or revolutionary work, however; Conrad apparently accepts the imperialist system and does not call for the end of colonial rule or for African nations’s and peoples’s independence. The African characters he writes do not seem capable of leadership or self-governance.
Marlow himself is more of an anti-hero than a hero. Initially embracing his role as a company agent, he seems to expect a reward or promotion for the successful completion of his mission to find Kurtz. Shielded from his internal contradictions by an aura of self-righteousness, he nonetheless reports others’s critical comments about him. The Central Station, manager, for example, wryly calls him one of “the new gang—the gang of virtue.”
Although Marlow is concerned about, and even frightened by, the excesses of imperialism, that concern seems more pragmatic than morally absolute. Abuse of power will lead to “reprisals,” and thus to loss of lives. In criticizing the high taxes, for example, he notes that their imposition resulted in

all kinds of tyranny, brutality and subsequent reprisals by the natives. In one concession alone one hundred and forty-two Africans were killed. The spirit of bitterness and hatred generated in the people was quite terrifying.

Marlow’s attitude certainly changes after he witnesses what Kurtz has become, but he still clings to the underlying concept of “the work of the world”: the benevolent paternalism of a Kipling-type white man’s burden. His criticism of the men in the Eldorado group, for example, is about their particular slant, not the fundamental character of the enterprise:

[T]here was not an atom of foresight or of serious intention in the whole batch of them, and they did not seem aware these things are wanted for the work of the world.