Slaughterhouse-Five question

That's a good point. They're both used as transitional phrases, right? I haven't read it in a while, but I guess the 'so it goes' moments stick with readers a bit more because the deaths they follow tend to resonate. If I remember correctly, the way Vonnegut sets up and uses the phrase, it becomes a pretty hard punch to the gut by the end. And who doesn't remember getting socked in the stomach? I'll definitely grab the book off the shelf tonight and compare how/when he uses the two phrases -- there's so much to learn from Vonnegut.