You Don't Necessary Understand The Idea Now
When you read something, you're trying to acquire information. Then, your brain processes the information into something you can understand. However, your brain don't necessarily understand the idea that it processes, perhaps the idea is too deep, or perhaps you don't have the knowledge to support understanding the current content read. Test yourself, provided you doesn't linger in the field of mathematics, and pick up a textbook of calculus where its page are filled with formulas. What does your brain tells you? Headache. Painkillers. Stop Reading!!!
In fact, it's not only difficult concepts that restrict one's understanding; it could be one's prior experiences. If you never lose something, you won't actually know what lose something feels like. Similarly, some self-help books out there requires prior experience, that you have experienced something, to synchronize with its contents, to understand and feel that, what it says is true, and what it says may help you, fully or to an extent. It makes sense that, if you don't understand the content now, perhaps put it until latter, and you could understand the content.
From one's viewpoint, one used to try reading Stephen Covey's "The 7 Habits"; but when one bought the book, the impression after reading one chapter is: The English's too difficult (One isn't a native English speaker), the font size's too small (hurt my eyes, urrrggggg), and the more one read, the blurrer one get. What it's trying to tell me is, one saw all the negatives that discourages one from continuing the book, so one put it off. About (slightly more than) two years later, one picked up the book again, and this time, it's a smooth read. Reason: one experienced some caveats mentioned in the book that worth one's attention to continue reading despite the negatives, and now that it is "one's business", it's easy to relate to the point mentioned in the book. Then, it somewhat helps me through.
Still, one learnt view experience, deep friends aren't made in a few months, without both sides' agreement on pushing the boundaries effortfully. If one retracts, it's almost impossible to continue. Hence, some of the tactics that requires both side's intervention lead to breaking of friendships rather than bonding. Reason? The other person find it too annoying to continue the relationship if you try to follow by the book, and the feeling get enlarged to become "you're annoying" and "I don't want to see you anymore".
There's another book which have the same matter. "Thinking, Fast and Slow" by Daniel Kahneman et. al. It speaks of some heuristics, biases, and mathematics. Of course, six years ago, one picked up the book and read 10 chapters from it. That's quite a lot, considered the book having 40+ chapters. Yet, that's about it. The book starts off interesting, then, one slowly lose interest in it, because at that time, one is too occupied with learning how to recuperate relationships (a.k.a. friendships), how to make new friends, and these doesn't have significant help towards the problems at hand.
Six years later, that is, few months ago, one picked up the book again, this time finishing the book in a week. This time, one could relate to the biases, heuristics, that is mentioned in the book, how one had seen the world and missed out the other part of the world. Of course, to fully put it into action is another effortful process which one haven't done yet; but at least it raises awareness in something that one feels interested in; one's blind spot in the past.
Thing is, when you put off a book until later, you may think: oh, I wish I had read this book earlier. No, don't think like that. It's not necessarily true that if you read this book earlier, you would've solved some problems. How you solve a problem isn't necessarily shaped by a book that you've read, though it may have influences to a certain extent. Similarly, how do you know you would have understand the book as how you understand it now without the prior experiences from the number of years you missed? You may not even understand what the book is trying to tell you the first time you saw the information. We aren't gods, we can't bring back our prior experience to the past, nor are we capable of time travelling to the past. What's passed is passed, try to look forward.
Back to the topic, in conclusion, if you don't understand something now, just take a breathe and shelf it. It's not like it's gonna disappear miraculously (without accidents like fire). Who knows, in the coming future, when you saw the unfinished book and picked it up again, you could understand the idea? If you don't understand the idea now, leave it for latter.
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