Somewhere in your library, a novel is quietly making the same argument as a history book three shelves over.
You'll almost certainly never notice - not because you aren't sharp enough, but because nobody can hold twelve different books open in their head at once. Working memory taps out around four or five.
As an avid reader myself, I stumbled on Mortimer Adler's "How to Read a Book" a few years ago, and he had a name for the thing that's missing: syntopical reading - the highest of his four levels, where you read across many books at once, around a question you bring to them rather than one any single author set out to answer.
Nobody writes that synthesis - but you do, by holding the books together.
It's also the level almost no one sustains, because past a handful of books it stops being thinking and turns into bookkeeping.
So I built a tool for the bookkeeping part. Point it at your library and it finds "trails" - passages from different books linked by one question you bring it - and drafts a synthesis that stages the authors against each other.
Ask "how should power be limited?" and it runs Machiavelli against Mill against Aristotle.
Ask "what does a good life actually require?" and Marcus Aurelius, Montaigne, and Thoreau end up in the same room.
Ask "why do people dig in instead of changing their minds?" and it sets Francis Bacon beside Nietzsche beside Kahneman - minds four centuries apart, arguing a question none of them framed the same way.
Whatever you ask, it leaves the tension open for you to explore rather than tying a neat bow on top of it.
What it won't do is think for you, and that's the point. It doesn't read the books and it doesn't settle the question - it surfaces the connections and lays out the raw material so you can do the harder part better. A trail is scaffolding for a question you already have, or one you may have one day - not a substitute for having one.
It's a little technical, but I've got step-by-step instructions on what you need and how to set it up. Point your LLM of choice to the README file and it'll help walk you all the way through. This only works on ePUB files right now (anything you have in an electronic library), but there are tons of free and legal sources of books and material online, also noted in the repo. There's also a public-domain demo included, so you can test drive it before going super deep on the full tool.
This has been amazingly useful for me, and I hope you find it just as useful.
You can find it here: github.com/WCJR-2029/syntopic-reading