ETA: Okay, I’ve recently found out that this quote is not Vonnegut, although he did write something similar to this in a letter to schoolchildren. That letter was posted to three–ring’s blog with her commentary posted below. Her commentary was copy-pasted to Facebook as being written by Vonnegut, and it’s been passed around that way ever since. Proof here.
I’m fixing this post with proper attribution. I did do a quick web search before posting this, but apparently it was too quick. Bleagh.
This is a nice anecdote, and it’s meaningful and valuable in its own right, but it’s not Vonnegut.
The source seems to be this 2020 Tumblr post, where the OP text is someone’s own anecdote following a Kurt Vonnegut extract. I guess someone’s read the post and got confused as to where his bit ends.