The Island of Doctor Moreau by H. G. Wells

The study of Nature makes a man at last as remorseless as Nature. I have gone on, not heeding anything but the question I was pursuing; [Dr. Moreau responds to his creations being called abominations; ethics doesn't come into it]

“This silly ass of a world,” he said; “what a muddle it all is! I haven't had any life. I wonder when it's going to begin. Sixteen years being bullied by nurses and schoolmasters at their own sweet will; five in London grinding hard at medicine, bad food, shabby lodgings, shabby clothes, shabby vice, a blunder,—I didn't know any better,—and hustled off to this beastly island. Ten years here! What's it all for, Prendick? Are we bubbles blown by a baby?” [Montgomery musing on the meaning of life]

...he got up, and went for the brandy. “Drink!” he said returning, “you logic-chopping, chalky-faced saint of an atheist, drink!” [A drunk Montgomery pressing Prendick]

I may have caught something of the natural wildness of my companions. They say that terror is a disease, and anyhow I can witness that for several years now a restless fear has dwelt in my mind. [Prendick analysing his experience on the island]