"Pierre Menard, Author of the Quixote" is a story about a man whose passion project is rewriting Don Quixote, that is, arriving at exactly the same text as Cervantes, but from his own experiences. The narrator quotes the same line from both and observes that the remark by Cervantes is empty rhetoric, while the statement by Menard alludes to a whole school of philosophy that did not exist in Cervantes' time. So, "Though they are verbally identical, Menard's is infinitely richer."
I wasn't going for a deep-lore reference, just a bit of silly wordplay about the title.
That paragraph begins,
Weizenbaum replies,
It's a snidely jokey response to an argument that Weizenbaum didn't make!