I read an average of two books a week, and have done so all my adult life. (Before then, I read even more.) Not only that, but when I really relate to a topic, I write notes in the margins and highlight important parts, and because most of what I read is non-fiction, one would think that I have filled my head with close to 3,000 books worth of information, knowledge, and maybe even some accidentally accumulated bits of wisdom.
The problem is that apparently my mind has been like a river, with a torrent of information flowing through it but very little staying behind in deep pools of knowledge. To give you an example of how bad it can be, on a recent trip I read Roy Baumeister’s book, Willpower. I found the book fascinating and full of good sense, but I also had the strange feeling that some of the stories were vaguely familiar. When I returned home I checked my bookshelves and discovered that I already owned a copy of the book which I had read a couple of years before and filled with highlights—many of them the same exact ones that I highlighted this time!
So, while it’s great to constantly refresh your stocks of knowledge, I’ve learned that there is a huge difference between lifelong learning and lifelong reading.
It’s an illusion of learning. When I read a book and the ideas make sense, it’s easy to fool myself into thinking that just because I get it now, I will still have it when I need it. You probably remember your school days when everything seemed so clear while you were studying but you could not bring it to mind when you needed it for the test.
Like so much in life, things seem easy until you actually put them to the test. That’s when you find the gaps and weaknesses in your understanding, when you realize how little of what you have read or heard has actually stuck in your mind. If you can’t remember it or apply it when you need it, the time you have invested in learning it the first time has been wasted.
Just like a wild river needs to be dammed to capture the benefit of its power, the secret to retention and understanding is testing. Don’t wait for others to test you, or for life to test you, test yourself. Test yourself by trying to explain it aloud, either to someone else or just to yourself. You can also write down a summary of the ideas, and then go back and check yourself.
Researchers have compared various learning strategies, including highlighting, or reading the same material several times, and have found that the single most effective method of really learning is testing. That’s because when we pull something out of memory, it’s not like opening that drawer in our minds where we stuffed the information—the memory is reconstructed each time we need it. The more we reconstruct it, the easier it is. Testing yourself strips away the illusion of learning and exposes what you do or don’t know.
But testing doesn’t just test—it teaches. It teaches in the same way that lifting a heavy weight several times to failure makes you stronger. You have to find your limits in order to exceed them which is why when testing yourself, the best thing you can do is fail. If you haven’t failed you haven’t found your limits. Failure doesn’t cost you anything, except a little extra time—but that time makes all the difference.
How would you apply this? After you read a page or a chapter or even a whole book (depending on the density and difficulty of the information), set aside a few minutes and try to explain the key ideas out loud or on paper. Explain does not mean a bullet-point listing of the key points. It’s an actual description using full sentences that links the ideas together in narrative or causal links. If you have trouble remembering a key piece of information, resist the temptation to check back—really test yourself by trying to fill in the missing pieces to make complete sense. Then, go back and check yourself. When you find you’ve left out a key point, try again.
It can be devilishly hard to do the first few times, but it does get easier. After you’ve done it enough times, you’ll find that the nature of your reading or listening will also change. You will begin mentally organizing the information in ways that will be easier to retain and call to mind when you need them.