A fascinating book to re-read in a world of QAnon. Reading this book, you suspect that Eco himself is gripped by madness but dispenses with it through fiction. Eco appears to be using some sort of meta-irony by writing himself into the story as Belbo, a character unable to create original fiction but instead only rewrap and combine existing fictions. Eco, of course, is doing this to some degree through his characters: he creates an entire novel that is itself an elaborate pun, wrapping huge swathes of history.
The wryly hidden commentary about the way that conspiracy theories warp the mind are perhaps the best parts of this book, piercing through Casubon’s descent into madness:
[O]ur brains grew accustomed to connecting, connecting, connecting everything with everything else, until we did it automatically, out of habit. I believe that you can reach the point where there is no longer any difference between developing the habit of pretending to believe and developing the habit of believing.
You sometimes seem profound, but it's only because you piece a lot of surfaces together to create the impression of depth, solidity. That solidity would collapse if you tried to stand it up.
Reading this book can be a real chore as so much of it is just long lists of historical minutiae dubiously linked together, but the end result is a rewarding look into the mind melting under the weight of a constructed story.