I found Echopraxia a disappointing follow-up to Blindsight, because the thematic core was much harder to grok, and it felt diffuse and attenuated. It's very hard to write a novel that explores what it means for scientists to encounter the limits of scientific rationality as we understand it.

Interestingly, (and apropos) McCarthy's last, Stella Maris, I think, did a much more eloquent job of exploring the same themes. Stella Maris is astounding, it's cosmic horror without the 'supernatural.' Instead there's only Gödel and Metzinger.