[…]; it had been a costly war despite the valiant predictions of the Pentagon and its smug scientific vassal, the Rand Corporation—which had, in fact, existed not far from this spot. Like the apartment owners, the corporation had departed, evidently for good. No one missed it. (2.2)
"Ennobled violence" is the belief that violence, such as war, will solve the world's problems—that dropping an a-bomb will end violence with extreme prejudice. This quotation lets us take a good guess at how well that turned out for the world in this novel.
In retiring—i.e., killing—an andy, he did not violate the rule of life laid down by Mercer. You shall kill only the killers, Mercer had told them the year empathy boxes first appeared on Earth. (3.19).
Check out the language Rick uses to consider his violence acts toward androids. The word "retiring" gives him a mental work around to the fact that he's doing violence that is against Mercerism. That's some classic doublespeak right there—and it also makes us think about retirement parties in a new light, know what we mean?
[…]; the .38 magnum slug struck the android in the head and its brain box burst. The Nexus-6 unit which operated it blew into pieces, a raging, mad wind which carried throughout the car. Bits of it, like the radioactive dust itself, whirled down on Rick. (8.78)
This description of Polokov's death hints at how Rick views violence toward androids at this point in the novel. On the one hand, the language of the bullet shredding through Polokov's head is ultra violent. On the other hand, words like "Nexus-6 unit" and "brain box" are weirdly sterile. We're so confused. How are we supposed to feel? Someone hold us.
[…]; even without the Penfield mood organ at hand his spirits brightened into optimism. And into hungry, gleeful anticipation. (8.92)
Look at that word "hungry." It's as if Rick is a predator, prowling for his next meal, and in a way he is. If he doesn't retire those andys, he doesn't get paid—and you can buy your weekly supply of Hot Pockets without cold, hard cash.
"And she made no effort to keep us from seeing her. As if she didn't care."
"No, she didn't care," he said. "Rachael wouldn't give a damn if you saw her; she probably wanted you to, so I'd know who had done it." (20.17-18)
Rachael wants to hurt Rick for what's he's done—violently. Sounds like Dick agrees with Martin Luther King Jr., who said that violence begets violence (source).
Resch, you're an android, he thought to himself. You got me out of this place and here's your reward; you're everything we jointly abominate. The essence of what we're committed to destroy. (11.41)
Could this be change in Rick's relationship with the violence he does to androids? It sure looks like yes. Yes, he'll probably give Resch the old laser tube should the Voigt-Kampff confirm that he's an andy, but Rick isn't as hungry for the hunt as he was in the last passage.
"I see a pattern. The way you killed Garland and then the way you killed Luba. You don't kill the way I do; you don't try to—Hell," [Rick] said. "I know what it is. You like to kill. All you need is a pretext." (12.62)
Rick doesn't like the way Resch retired Luba Luft, and it shows. Notice how he said Resch killed Garland and Luba, not retired. At this point, Rick is riding the crest of the character arc right at enlightenment.
Pris had now cut three legs from the spider, which crept about miserably on the kitchen table, seeking a way out, a path to freedom. It found none. (18.45)
The novel takes a common form of violence (well, we hope not that common… ) and makes it horrifying. Reading about Pris torturing the poor spider is really terrible. Yet violence to creatures as small as spiders, bugs, and ants is commonplace in our world, so much so we rarely pay attention to it. (Although, seriously, if you're going to kill a bug, just do it quickly and get it over with. No need to torture it.)
[Rick] shot Roy Baty; the big man's corpse lashed about, toppled like an overstacked collection of separate, brittle entities; it smashed into the kitchen table and carried dishes and flatware down with it. Reflex circuits in the corpse made it twitch and flutter, but it had died; […]. (19.44)
Rick guns down Roy Baty, but his view of this android's death is a little more vivid, a little more detailed than Polokov's. Instead of "brain box"—the way he describes the first android he kills—Rick sees the 'droid as a "corpse." And that's a pretty human word.
At that moment the first rock—and it was not rubber or soft foam plastic—struck him in the inguinal region. And the pain, the first knowledge of absolute isolation and suffering, touched him throughout in its undisguised actual form. (21.17)
Violence actually teaches Rick to see how isolated he is. Violence isolated Rick from those he loved, and all alone on the mountain, violence is being done to him.