In Heart of Darkness, what is meant by the term "efficiency" in the context of imperialism?
At the beginning of Heart of Darkness, Marlow is talking about the Romans. He talks about how the Romans were nothing but thieves and murderers. They were unable to actually rule other peoples. After speculating on how the Romans felt, he says
Mind, none of us would feel exactly like this. What saves us is efficiency—the devotion to efficiency.
Efficiency, then, is what Marlow thinks separates British imperialism (and perhaps other imperialism) from the imperialism of ancient Rome. Ironically, the rest of the book shows that this idea of modern efficiency is totally illusory.
In the context of imperialism, efficiency simply means exploiting the colonized country without wasting resources. It means that the imperial power will go into a backwards country and use modern methods to make sure that the goods (like the ivory that Kurtz is getting) that make imperialism worthwhile will come out in a constant flow. It means that the imperial power will act rationally. It will not allow its resources (like the sunken steamer at Central Station or the laborers at Lower Station) to be wasted. The reason that Europeans deserve to be imperial powers (in this view) is because they do not waste resources like natives do.
Efficiency in imperialism, then, has to do with extracting the most possible resources with the least possible amount of waste. It is not something that the white imperialists in Heart of Darkness achieve.
In chapter 1, the unnamed narrator hears Marlow speak about the Roman conquerors who overtook England in centuries past. Marlow says the following:
"Mind, none of us would feel exactly like this. What saves us is efficiency—the devotion to efficiency. But these chaps were not much account, really. They were no colonists; their administration was merely a squeeze, and nothing more, I suspect. They were conquerors, and for that you want only brute force—nothing to boast of, when you have it, since your strength is just an accident arising from the weakness of others."
In this passage, Marlow compares the brutality of ancient conquerors to the European conquerors who are currently setting up empires in Africa. The word "efficiency" is a euphemism, or a word that tries to gloss over the negative and brutal reality of a concept. While the conquerors of yesteryear used "brute force," the European imperialists of Marlow's day do not need this type of force because they have "efficient" forms of technology. In reality, of course, the European imperialists of Marlow's day are also brutal, but they use forms of brutality that are more removed, such as guns and ships. They can use their efficiency, or technological superiority, to brutalize the people they attempt to control, but at a greater remove than imperialists in the past.