I think he is offering to help you learn the method of loci (memory palace technique) and is giving you a series of visualization exercises that you can try, at least as a way to figure out how to start with the explanation of the technique. (Arun512, correct me if I’m wrong.)
If you answer the questions, there will probably be some more questions.
If you want to learn more about the method of loci, there’s also a description in the free ebook.
There is some research that says reading on paper is better for retention than reading digitally, but I wouldn’t take the idea too far. I think that reading digitally is better than not reading at all.
There’s an article about a person who read 200 books per year. If I recall correctly, he used all different kinds of formats to consume books (paper, Kindle, audio) depending on what was convenient at the moment.
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