[BeetleB]

I used to believe that my reading shaped me despite me forgetting 90% of what I read, but I no longer believe it. Or at least, I have no good reason to believe it - it seems more wishful thinking.

I've even had experiences where I was profoundly affected by some interesting material, only to later realize that I had encountered that material (in a different book) less than a year prior. I hadn't ignored the material the first time, and had been affected by it then as well. I'm pretty sure it didn't shape me at all.

Whether to take notes or not depends on the purpose of reading nonfiction. When I read biographies, I'd like to get the bigger picture rather than the details - so if I do take notes, they are very sparse (e.g. summarizing the major points - perhaps 1-3 pages worth). With some other books I copy quotes of insightful points (e.g. reading The Demon Haunted World, I was struck by how critical he is of the behavior of many skeptics, and noted the irony that many skeptics had recommended the book).

But when it comes to potentially useful self help books: There's really no point in reading them if you don't take serious notes. They don't make for great reading, and may actually have useful material for you for life.

Books like Gladwell's: They're mostly for entertainment. It's fine not to take notes, although it's probably better to read fiction itself.