"I think it'll make you feel better," Sam said, quietly. "In the long run. It'll feel pretty crappy at first."
Cas's response hadn't made him particularly hopeful that this argument, or any other, would have much effect. But he had to try. "You can't find the answers you want about life, or mortality, by taking a drug. Artificial bliss... isn't that what heaven wanted us to have, in heaven, after the world ended? Didn't we... didn't Dean show you that it was wrong, that it's the suffering and the struggling that really matters? You're not stuck in a hopeless war anymore, you can get through the crap you're dealing with. But only if you try."
He was silent for a long moment, letting that sink in-- for him, as well. It was the first time he'd really voiced his opinion of what Cas was doing. "And yeah, I think it'd make me feel better, too. To be able to get to know the... real you, the one that you're trying to anesthetize so that you can pretend he doesn't exist."