The Interpretation Of Dreams was a blockbuster in its time; Decline Of The West similarly so. So what happened?
Ideas and philosophies lose popularity for many reasons (e.g. they might be wrong) but maybe something else drives their obsolescence. When a book first comes out everyone reads it with interest, and form their own opinions as they try to apply the ideas to themselves and their world. But then other people write about it, and soon those books of criticism (not to mention the shorter articles) outnumber and overwhelm the primary source, so that within a generation people only read other people’s opinions of those ideas.
A trivial example. Regardless of whether he was right, it’s undeniable that The Interpretation Of Dreams had a huge impact on the western world when it was read. Now, everyone knows Freud was way off; yet I’ve never met anyone who has actually read The Interpretation Of Dreams. “Well, I’ve read parts.” Most people know Freud was wrong because fairly unsophisticated thinkers have explained him away in language more fitting to the newer generation; the antithesis used updated market research.
What would happen if everyone suddenly went back to the originals? The response is that we’d immediately realize it is nonsense because people know more about such things, but it begs the question: what things? How do you know? What would happen if the originals themselves were re-written in a modern style?