| Paul Graham wrote a 2014 essay saying basically this: http://www.paulgraham.com/know.html Reading and experience train your model of the world. And even if you forget the experience or what you read, its effect on your model of the world persists. Your mind is like a compiled program you've lost the source of. It works, but you don't know why. The fact that I dug up this quote proves I remember some things I've read :) FWIW I take 1-3 sentences of notes on articles I read, and few paragraphs of notes on books I read, and put them in my personal wiki. I find this not only helps retention but it helps understanding, by forcing hyperlinks to related work. Hyperlinks model the way your mind works. I elaborate on that here: https://news.ycombinator.com/item?id=24536687 Funnily enough it cites the same PG essay. It also echoes the article here, which I strongly agree with: Finishing the book is optional. You should start a lot of books and only finish a few of them |