Quote 142
"It was as unreal as everything else - as the philanthropic pretence of the whole concern, as their talk, as their government, as their show of work. The only real feeling was a desire to get appointed to a trading-post where ivory was to be had, so that they could earn percentages. They intrigued and slandered and hated each other only on that account—but as to effectually lifting a little finger - oh, no." (1.56)
Marlow is appalled by these pilgrims' depth of corruption. It seems utterly "unreal" to him that men could be so hypocritical. The unifying trait between them seems to be greed. (Nice words coming from someone who's heading to the Interior for profit himself.)
Quote 143
"I went to work the next day, turning, so to speak, my back on that station. In that way only it seemed to me I could keep my hold on the redeeming facts of life. Still, one must look about sometimes; and then I saw this station, these men strolling aimlessly about in the sunshine of the yard. I asked myself sometimes what it all meant. They wandered here and there with their absurd long staves in their hands, like a lot of faithless pilgrims bewitched inside a rotten fence […] I've never seen anything so unreal in my life." (1.54)
Marlow convinces himself that the only way he can remain sane is to work by himself, obsessing about fixing the steamboat. However, he finds himself sneaking peeks at his fellow men and discovering that everything is as absurd as he'd feared. The men are so aimless that Marlow compares them to pilgrims who have lost their faith or been bewitched. He seems to hate their aimlessness because it contradicts so sharply with his keen sense of purpose.
Quote 144
"He [Marlow's white companion] was very anxious for me to kill somebody, but there wasn't the shadow of a carrier near. I remembered the old doctor—'It would be interesting for science to watch the mental changes of individuals, on the spot.' I felt I was becoming scientifically interesting." (1.50)
Both Marlow's companion and Marlow himself find themselves going mad because the white friend has obviously been attacked. He wants Marlow to kill the assaulters, but there is nobody around. Marlow jokes that because his world no longer makes sense, he is becoming "scientifically interesting."