Not that a steady diet of only the old books is to be preferred. Simply that there is much to learn, and much to be held in memory, which can be forgotten willfully or through ignorance.
Which leads me, of course, to Project Gutenberg. Where you can find the old books for free and easy reading. Some may be a challenge, and some are awful piffle. Some, though, are worth the effort and will deepen your knowing of the world and who we came from.