[kkfx]

Those who measure "knowledge" like a liquid quantity do not know what culture means, sorry for being harsh but that's is.

Books are VERY good, of course if well written, to share knowledge, not to improve someone profits, of course, topic specific. Of course they are a single package of something, they are not meant to be "games-books" or other things. So books are not universal for anything and anything. But they are the best way to transfer most of human knowledge in an asynchronous and distributed manner.

Audio books, videos might be superior for some cases, but a fairly limited set of cases. Song are also very valuable but for an even smaller set of cases. And no, knowledge can't be measured like a liquid to be drink, similarly we can't "give culture" like some modern schools stating targeting high culture peaks but really targeting formation of Ford model workers to be useful idiots in the classic Greek's sense state.