So how does the billionaire book lover remember what he reads? The trick, he says, is context.
"If you read enough, there's a similarity between things that make it easy, because this thing is like this other thing. If you have a broad framework, then you have a place to put everything," Gates says in the Quartz video, "How Bill Gates remembers what he reads."
When you come to a topic with a base layer of understanding, then fitting in new tidbits of information makes them easier to remember.
"So, incremental knowledge is so much easier to maintain in a rich way," Gates says. "At first it is very daunting but then as you get the kind of scope, then all these pieces fit in."
If you want to learn about science, for example, Gates says reading the history of scientists and reading about the progress they made can give you the context or framework to help you remember the details.
"So you have the timeline, or you have the map or you have the branches of science and what's known and what's not known," Gates says in the Quartz interview.
Reading is more than a pastime for Gates. In 2017, Gates told Time that reading is "absolutely" essential to success.
"You don't really start getting old until you stop learning," Gates told Time. "Every book teaches me something new or helps me see things differently. I was lucky to have parents who encouraged me to read. Reading fuels a sense of curiosity about the world, which I think helped drive me forward in my career and in the work that I do now with my foundation."
Gates is rather fastidious in his reading habits: He always finishes a book he starts, whether he agrees with it or not.
"I refuse to stop reading a book in the middle, even if I don't like it," Gates told Time. "And the more I dislike a book, the more time I take to write margin notes. That means I sometimes spend more time reading a book that I can't stand than a book that I love."
And if material he is reading doesn't make sense within his existing understanding of a topic, he will actively seek out an explanation.
"So it's fun to say, okay, this is where this belongs and does this contradict something I knew before? And I better look that up, I better figure it out," Gates tells Quartz.
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