Book rereading is a topic that has long been debated. Some argue that rereading is a waste of time, while others encourage it.
Whether it is worth rereading a book will depend on reading goals. If the goal is to better understand the book, then it is worth rereading, but only if one is rereading actively and quizzing oneself. If the goal is entertainment – one can reread a book as many times as they find it enjoyable.
Read on to learn more about the science behind rereading books and when it is a good idea to reread them.
1. How to decide whether you should reread a book?
Whether you should reread a book will depend on your reading goals. In a famous book on effective reading (How to Read), Adler and Doren outlined that there are three main goals of reading:
- Reading for entertainment – requires the least effort, an activity that you perform for enjoyment, such as reading a fantasy novel.
- Reading for information – a low-effort activity that leaves you essentially unchanged, e.g. reading a newspaper.
- Reading for understanding – an effortful activity that changes how you understand things, e.g. reading a historical book that makes you interpret your country’s history in a new light that you have not considered before.
I believe that these goals can be further simplified into two main groups:
- Reading for enjoyment (information or entertainment)
- Reading for learning (understanding)
Of course, these categories are not mutually exclusive – you might learn something new while reading for enjoyment and vice versa. However, the main difference is the primary goal behind your reading – as long as you achieve your primary goal everything else is just a nice bonus.
1.1 Rereading for fun
If you are rereading a book for fun – there are no hard and fast rules here since the main objective is to have fun. If you enjoy rereading Harry Potter books over and over – it is totally fine, knock yourself out.
“A book that this year I go through all the time at least once a week is The Untethered Soul, and this is a book, which I have reread so many times, but it … really calms me down when I’am very anxious or over stimulated.”Elizabeth Filips
In fact, having books to which you can always come back to uplift your mood is a great idea. For example, a famous YouTuber, Elizabeth Filips, has what she calls her “safe space book” – that she generally rereads multiple times to feel better.
Of course, if you just keep rereading the same book over and over again, it can get dull quickly and you might stop enjoying it – if that is the case feel free to drop it. After all, if your goal is to have fun, then you should stop it when it is not fun anymore.
Furthermore, you might want to consider reading multiple books at the same time since then you can both enjoy the novelty of new books and have a great book to which you can always come back when you feel like it.
1.2 Rereading for learning
When it comes to rereading with the primary goal of learning or understanding the book better, things become more complicated. Generally, while rereading can be helpful for learning, most people do it incorrectly, especially students.
In Make It Stick, an excellent book on learning and memory, the authors (2 of whom are leading researchers in learning and memory) caution against rereading, since the evidence from numerous studies reveals that rereading a text and massed practice (single-minded repetition of something you are trying to memorize) are ineffective learning techniques.
“Rereading text and massed practice of a skill or new knowledge are by far the preferred study strategies of learners of all stripes, but they’re also among the least productive. “Make it Stick, Brown, Roediger, and McDaniel
According to Brown, Roediger, and McDaniel, it is much more effective to engage in retrieval practice (recalling ideas and facts from memory) instead of just mindlessly rereading.
For many, this might sound counterintuitive since generally quizzing oneself is difficult while rereading text is easy and comes naturally. In fact, rereading is a favored learning strategy for learning among many students. However, studies reveal that this intuition is misplaced.
For example, in a 2006 study, Roediger & Karpicke asked 2 groups of students to learn a small section of a textbook. The first group had to learn by reading the text 4 times. The second group had to learn by reading the text only once and then attempting to write down everything they could remember from what they read 3 times (basically 3 tests in a row).
Then after learning, these students had to predict how well they have learned the material. Lastly, after 1 week both groups had to take a test to see how well they remembered the text.
The results were surprising, while the rereading group (1) thought that they will perform better (their predicted performance was 30% higher than that of the retrieval group (2)), the retrieval group (2) remembered significantly more than the rereading group (1) – in fact, they remembered 50% more information than the group who just reread the text instead of quizzing themselves.
Does this mean that there is no point in rereading books if your goal is to learn? No, but the existing studies provide a lot of compelling evidence for why you should not reread text immediately after you have read it if you want to actually remember and understand.
Instead when you are reading a book with the goal of learning you should quiz yourself – after reading each paragraph, page, and chapter, ask yourself: What were the main ideas in this paragraph or chapter, what examples and arguments did the author use to support their claims, etc.
“Periodic retrieval of learning helps strengthen connections to the memory and the cues for recalling it, while also weakening routes to competing memories. Retrieval practice that’s easy does little to strengthen learning; the more difficult the practice, the greater the benefit.”Make it Stick, Brown, Roediger, and McDaniel
Try to write down answers to these questions without looking at the book, then go back to it to check. While this process might seem time-consuming and difficult, according to Brown, Roediger, and McDaniel, such difficulties can be described as desirable, since they help to strengthen our learning and by learning more effectively we end up saving time in the long run.
Of course, you might not want to memorize the ideas from each sentence in a book as it might take ages. Instead every time you approach a book with the goal of learning you should ask yourself what you actually want to learn from it and how much time you want to dedicate to this learning. Maybe it is sufficient just to distill and memorize 1 key idea from each chapter.
Furthermore, rereading is not always completely ineffective, in their book Brown, Roediger, and McDaniel explains that, while multiple rereadings in close succession yield limited benefits, rereading the material after a meaningful break (e.g. 1-2 days) can result in better learning.
“Practice that’s spaced out, interleaved with other learning, and varied produces better mastery, longer retention, and more versatility.”Make it Stick, Brown, Roediger, and McDaniel
This is consistent with, the findings of Hermann Ebbinghaus and the forgetting curve, which reveals to us that spaced repetition (spacing out your learning sessions instead of cramming) is a more effective way of learning.
Therefore, when it comes to rereading with the goal of learning you should do the following. Each time you read, engage with the material actively – periodically quiz yourself on what you are reading, if needed take notes, etc. Make sure that you are not rereading in close succession, space out your rereading sessions and in each session put the focus not on reading but on the retrieval practice.
2. How often should you reread books?
If you are rereading with the goal of enjoyment, there are no rules – feel free to reread as often as you like, or do not read the book again if you do not feel like it.
Of course, if you keep reading the same book over and over it might get dull quite fast, so you might want to consider spacing out your reading sessions, by reading other books or reading multiple books at the same time.
However, if you are reading with the goal of learning and increasing your understanding, you should consider spacing out your reading sessions since studies have shown that rereading in close succession is ineffective.
The general rule is that “It makes sense to reread a text once if there’s been a meaningful lapse of time since the first reading“. This could mean a couple of days or more. Whenever you feel that you have forgotten the material in the book you might want to consider reading it again.
Furthermore, as mentioned above, research shows that you should quiz yourself frequently even before you finish reading the book fully if you want to boost your retention and understanding. So ultimately, what is important is not how often you reread the material, but that you read it actively and space out your reading sessions.