I did not know yet how far they were from the human heritage I ascribed to them. (11.24)
Evolution was a pretty new idea when Wells wrote The Island of Dr. Moreau, so it was still on everybody's mind (and it still is on everybody's mind). Prendick's thought here would have made the Victorian reader imagine evolution run amuck and threatening traditional views of morality.
The creatures I had seen were not men, had never been men. They were animals—humanised animals—triumphs of vivisection. (14.6)
Vivisection is hugely important to the text—so important, we gave it its own section in "Symbols, Imagery, Allegory." Obviously the word triumph is used with some irony here. It's not meant to suggest an actual triumph at all but rather the complete disregard for the morality of the situation.
"The physiology, the chemical rhythm of the creature may also be made to undergo an enduring modification, of which vaccination and other methods of inoculation with living or dead matter are examples that will, no doubt, be familiar to you." (14.11)
Can't have a science fiction novel without a little scientific mumbo-jumbo, right? Actually, Moreau is comparing his vivisection experiments to the idea of a vaccination or inoculation, something that cures or prevents a disease. It makes the process sound more morally sound. Of course, there's a reason we have the expression "the cure is worse than the disease." It's for moments like this.
"In our growing science of hypnotism we find the promise of a possibility of replacing old inherent instincts by new suggestions, grafting upon or replacing the inherited fixed ideas." (14.15)
Science's understanding evolves throughout the decades. Take hypnotism. We now use hypnotism to make suggestions. We do this either to help the person in therapy or for our own sick amusement as we watch them cluck like a chicken. But graft new ideas onto the mind? Don't think so.
"Then I am a religious man, Prendick, as every sane man must be. It may be I fancy I have seen more of the ways of this world's Maker than you—for I have sought his laws, in my way, […]." (14.26)
Moreau claims he's a religious man and a scientist. He suggests that religion and science are not in conflict—only the confused notion of religion that people like Prendick have. Once we filter out all the touch-feely pain-is-bad stuff, religion and science can get along swimmingly.
"You cannot imagine the strange colourless delight of these intellectual desires. The thing before you is no longer an animal, a fellow-creature, but a problem." (14.27)
This is maybe the single best line in the whole novel regarding morality in science. When Moreau's worldview renders pain and suffering a problem, or puzzle, he tips the moral scales to the side of the immoral. But Moreau is too high on his "intellectual desires" to notice.
There was no evidence of the inheritance of the acquired human characteristics [in the babies]. (15.6)
Moreau thinks he's evolution incarnate. However, if his creatures don't pass on the human characteristics to their babies, then he's not really evolving them at all. You'd think he'd realize that fact, but nope. He's just too pig-headed. (Okay, we'll admit it. Pun intended.)
[Montgomery] had fancied they might serve for meat, but a rabbit-like habit of devouring their young had defeated this intention. (16.1)
One of the great things about science fiction is that it can sometimes consider ideas before anyone else can even imagine their possibility. Here, we see Moreau's vivisection acting like an early equivalent of gene splicing. It's kind of freaky actually, like reading a crystal ball.
Had Moreau had any intelligible object I could have sympathised at least a little with him. I am not so squeamish about pain as that. I could have forgiven him a little even had his motive been hate. But he was so irresponsible, so utterly careless. (16.92)
According to Prendick, science needs a goal. To simply go poking about at the great mysteries of the universe is irresponsible, immoral. Science is the pursuit of reason, so it needs a reason to be. To balance that idea, some of the greatest discoveries in human history have been made by accident. We didn't want to make things too easy on you.
Then we went into the laboratory and put an end to all we found living there. (18.35)
Sometimes you just have to know when to call it quits. When your experiment kills you, yeah, time to call it quits.