Ask HN: How do you memorize things you read?

[boppo1]

— especially if they're technical you don't use them regularly at work?

For example, I don't work in finance (got the degree but my grades were abysmal), but I have a great deal of interest in the field, so I bought the CFA and CAIA curriculum. As I read it I grasp it and answer provided problems with no difficulty. But when I return to the material a few months later, I may as well re-read the whole thing for the amount of detail I've retained.

[reciprocity]

One of the most successful methods I've found for me is to rewrite the material. I haven't seen anyone suggest this yet.

By rewriting the material, you are recoding it. You are forcing yourself to think about the information differently: what you are doing is explaining it to yourself. This to me is far more effective than something like highlighting, because in rewriting that material, you are also clarifying your understanding.

[xboxnolifes]

Very much this for me. It's the reason I wrote notes instead of typed them in college. The intention was never to use the note for reference, but the act of writing them enforces your memory.

[shade]

Yes, this is my approach too - I'll take extensive notes and/or rewrite the material. The way I do thinking and learning is essentially to write things down on paper - it doesn't work for everyone, but it does for me.

I also happen to use fountain pens for it, but I think that part is optional. :)

[alexpetralia]

Posting an old comment of mine here (which relates to rewriting material as a retention aid): https://news.ycombinator.com/item?id=25302365

[reportgunner]

I do this all the time. I write things down and never come back to read them because I seem to remember the important parts.

[anttiharju]

+1

This is what I do for most of my university courses. It's super not efficient time-wise, but my grades have been generally good thanks to it.

Plus if I have to write an essay about anything related I can just ctrl+f the material I've written so far and get my facts straight very quickly.

[30minAdayHN]

This is a great suggestion. It worked quite effectively during my high school while preparing for college entrance. I used to rewrite a lot. Rewriting in combination of revisiting material with some frequency helped.

[gremloni]

I can vouch for this. I just gave an SDE a bad performance review because he could never recall any code he worked on or how it worked…

[thescribbblr]

+1

[andyxor]

Ben Franklin did something similar, he copied books by hand I think

[abetusk]

People are giving app suggestions (supermemo, Anki), which is great, but the underlying concept is "spaced repetition" [0]. Tools like Anki (and supermemo, I presume) give you flash cards at an interval based on the spaced repetition idea.

Our memory is structured so that we forget things at an exponential rate (exp(-a t)). The better we remember things, the smaller the coefficient (a). You can look around for pictures of "forgetting curves" [1].

The idea is that for new knowledge, the coefficient (a) is large, so you need to refresh your memory sooner. As you retain the knowledge (the coefficient gets smaller), you can wait longer before you need to refresh your memory. The exact coefficient is going to be dependent on the person, the type of knowledge (for the person), the context in which it's learned etc. etc.

A simple way to do this without flash card applications is to try to recall the information you've learned periodically. Can you recall it after a day? A week? A month? If you can't, go back to the information and relearn it, and try again, making sure to do active recall to refresh your memory.

Another trick is to try to explain the knowledge you've learned to someone else, or pretend you're trying to explain it to someone else, if you don't want to subject your friends to it. Often times a "why" will come up or some piece of it will seem arbitrary that you won't be able to explain, which is a good signal that there's a concept you've missed and need to review to understand it more deeply.

[0] https://en.wikipedia.org/wiki/Spaced_repetition

[1] https://elitemedicalprep.com/what-is-spaced-repetition-and-w...

[LittleFishyChan]

I’ve been using SuperMemo for almost 16 years, every single day. I can’t think of a better way to guarantee that I will retain stuff outside of using some kind of algorithm to tell me when to refresh desired information. I think of it more as “computer augmented memory” rather than “I’m letting the computer think for me.” I use it in the morning to review my cards but other than that I have little interaction with it (until I add more cards, which happens during periods of down time)

[jacquesm]

One of the best articles on SRS out there:

https://www.gwern.net/Spaced-repetition

[antegamisou]

It's very hard to actually comprehend any technically challenging concept without being constantly exposed to it. The more challenging it is, the more time you're going to need so it become something like second nature to you.

Take up as many relevant projects as needed to master the underlying theoretic aspects of whatever you're interested in, whether that's in math or programming. Don't get frustrated if you get stuck somewhere. You can always take a break and jump back to take a better look to any helpful readings to better understand some concept you may have missed earlier. Just make sure you're already pretty familiar with the very fundamentals first (e.g. don't expect good progress on a machine learning course without being already familiar with linear algebra - probability fundamentals.)

[strelka_]

As I was writing my answer you posted yours, and I found It very very helpful.

[Veen]

I tend not to memorize in that way. Reading gives me a basic familiarity with a topic and, more importantly, helps me understand where to find information when I need it. If I use a piece of technical information regularly, I'll just keep looking it up until exposure fixes it in my memory.

However, if it's something I do need to remember and can't look up, spaced repetition tools like Anki are helpful.

You should probably ask yourself whether it's worth the effort to memorize something that you only need every few months. So long as you have an understanding of the general topic, it's not hard to find technical specifics when you need them. Being able to reel off technical details from memory is a good party trick, but I've rarely found it to be useful in daily life.

[AndrewDucker]

Yup, same here.

I absolutely don't memorise things on purpose. I just use them, and try to remember where to look them up again.

Memorisation is a fancy tricky that doesn't gain you that much over knowing where to find the answer.

[sturza]

I have a "trick". My native language is not english. 99.9% of what i read is in english. Comprehension for me is also slow when just reading(at least once).

Memory, as i found out, works if you connect new knowledge to existing knowledge. Usually, when i read and understand something to the point of the "aha" moment is not sufficient. Just understanding something in that moment is not enough for storing in long term memory.

Here is the trick part: when i read and want to comprehend and memorise, i do the following:

  1. Read a paragraph/piece in english
  2. Get to the aha moment by re-reading until it makes a narrative in your head
  3. Once i have the narrative, i translate it to my native language and write it down(pen and paper > keyboard)

It's not fast, but there are many processes involved here that get to long term memory:

  1. first reading - getting the context of the material
  2. getting to the aha moment - means it's connected to something, and the new knowledge somehow filled the gap
  3. when i get to the narrative part, i can make a story and tell it to myself, in my own head "this is because of that etc"
  4. #3 is not sufficient, so i take a step further and process it by translating it - further cementing the "connecting to old knowledge" process
  5. #4 is also not sufficient, as the translation is not always clear when trying to explain it to someone else. here is where the longhand writing comes into play - writing is expressing your thoughts clearly. when this is done, i already went through a lot of phases of processing, that i can say i fully understand something without any rote memorisation: i can just use whatever old knowledge i have to recreate new knowledge and to assemble it based on the listener's (perceived) capabilities of understanding.

I know this works, because i have all the processes written by hand, in a notebook. Everything i explained here is a narrative that i constructed on the spot to explain my process. Keep in mind that this whole process of comprehension, memory, new knowledge and handwriting was new to me ±1 year ago.

Not sure this helps you directly but indirectly it should be able to guide you into figuring out what works best in your context.

  #edit: i still don't know how to format text in a comment

  #edit 2: figured it out

[mapster]

To retain facts and terminology, do you simply translate to native language to retain it?

[zoomablemind]

> How do you memorize things you read?

Memorizing short-term is relatively easier, provided there's sufficient comprehension and, well, ... association memory.

However, to retain some new knowledge, even just concepts, for a longer term and having it ready on-demand for me is very much dependent on how relevant such knowledge is to my present state of "know".

If the new concepts are too detached, even if I do grock them now, the only thing that would stay for long term is some feel of familiarity. Actively refreshing such knowledge is often impractical, as long as it remains not relevant to life. There are always tons of new topics to discover!

So, basically, for me some new knowledge retains long-term when it's made relevant in life or directly extends some already relevant knowledge.

No shame in forgetting, just know where to find it again or whom to ask. It's not futile however, as in encountering new concepts, sometimes an extension from known concepts grows naturally, kind of further forming the worldview. Good terminology helps a lot in connecting and retaining the dots.

[falcolas]

No need to memorize everything in this day and age. Memorization is super useful, but if it's not part of your day to day, looking it up when you need it is a more efficient use of time.

To that end, I'd instead recommend taking notes in a system that allows for full text search.

However, if you still want to memorize it, repetition will be your friend. Repeatedly reading the material will gain you familiarization with the concepts, and eventually the memorization. Spaced repetition (Anki et.al.) is the fastest, but simply reading regularly works too.

[prosaic-hacker]

TOC and Index method

If I have to test on a topic I know sort of intuitively but look thing up each time I do it because I do it infrequently I do the follow to have all the details current.

I take a trusted source of information on the topic and paste the text into a word processor that can build table of contents and Indexes. Step 1 I use the Multilevel TOC heading feature and create a heading for each paragraph of the document. Splitting long paragraph into pieces. The act of having to write headings per paragraph means you have pay attention to the core meaning of it. (I use a 5 or 6 level deep Toc)

Step 2. Create an Index at the end of the document and use the semi automated Key word tagger to mark all occurrence of an expression. It should given you a 1 level index entry with many page numbers. Go to each entry and add a 2 level index tag descriptor until all the page numbers have 2 level entries.

By the time you are done you will have visited this document from many angles and repeatably read the information and have a well integrated understanding of it. If the document has procedural steps to follow when you tag one of those sections decide if you know how to do that or repeat the process for practice.

[PeterisP]

I don't memorize; I try to learn a skill by applying it in practice on some project, no matter if real or a "toy" one; most of the skill will stick, but the memorization of all the facts facts is rarely relevant - any facts which were not required to apply that skill don't really need to be memorized and can be looked up easily when/if needed.

[MrDresden]

Organization & Repetition.

Any material which is worth knowing, but that will not become part of a routine (i.e coding patterns or structures that would be used everyday) which would enforce the learning through repetition will need to be reviewed/used/consumed at regular artificial interval instead.

I've had a personal wiki for years, and moved to Obsidian.md two years ago. Content that I find usefull or worth keeping is broken down and rewritten into my wiki.

Here it is important to note that simply copy pasting long form text from a source does not work as well as writing the content in your own style. Writing it down, and having to reason about the content as I am doing so helps me retain it for longer.

I then have a list of content that I review at regular intervals (weekly, monthly, quarterly, yearly, 3/5 years). These are simply links within my wiki.

The tricky part here is to not overload your future self. Sure I can write down pages and pages of information and just expect future me to consume it. But in reality I know there is a limit.

[boppo1]

I like this approach. I'm likely to overload future me though. How do you determine where the limit is?

[vubui]

You can't forget something if you understood it. A concept is internalized when one understood the concept. Techniques to memorize something is not effective. Even worse techniques are glorified. Then one spends a lifetime polishing the techniques to memorize what they wanted to internalize in the first place. It's a trap.

Want to memorize something? Try to really understand what's going on. You cannot forget something if you already understood it. If you can't recall it, then maybe it's not that helpful to you or you didn't understand it in the first place at all.

The techniques to memorize something effectively are organic, an effect when someone tries to learn in their own way effectively. Starting with techniques is a trap.

How many people who have used Anki or whatever forms of memorization became world class at what they do? It's a distraction.

[fartcannon]

I tried this technique in university. I ended up with B's and C's while my friends, who just memorized the exams, got magna cum laude.

Granted, I may have just been too slow to really understand the material in time for the exams, but it's worth mentioning that sometimes its better for your life to just memorize things.

[rahimnathwani]

This may (may!) be true for something like math concepts that build on one another.

But in OP's example, much of the CFA and CAIA is about man-made concepts, taxes and government regulations. What does 'understanding' even mean in this context? If you 'understood' what rule XYZ means about the fiduciary duty of a financial advisor, does that mean you'll always remember it, or be able to derive it from first principles, even 20 years in future?

[gremloni]

I feel like this has been said a lot and only works in very specific disciplines like physics and maybe math. Just grasping concepts isn’t always sufficient and memorization is underestimated.

[brentjanderson]

As others have noted, Spaced Repetition (I use Readwise, Anki is good too) is a good starting point. My workflow for trying to learn new concepts looks like this:

1. Have a habit to review 10 flashcards in Readwise [0] every day 2. As I read, stash snippets of interesting things into Readwise 3. If there are bigger insights I want to digest, I take notes using Dendron [1] and link those insights into other things I'm studying

Eventually, I want to integrate my markdown notes in Dendron with Readwise so that it's easy to block out something I want to review with Readwise in my notes, and for that to automatically show up in Readwise.

[0] https://readwise.io [1] https://dendron.so

[ai_ia]

> But when I return to the material a few months later, I may as well re-read the whole thing for the amount of detail I've retained.

I am trying to solve this particular issue in online learning. You may read a lot of books and watch quite a number of videos, but after few weeks or months, you remember zilch. Things are different when you are learning and applying, for instance, trying out a new framework or programming langauge library. However, most of the things are not really straightforward to "apply and understand".

You are always going to forget, no matter what. The real question is can you recover (faster) and retrace whatever you have learned. Think about stuffs you read up in high school or universities or colleges. How much of it is you can recollect? Can you "recover" what you have learned and "resume" from the point you left?

My solution is creating a conversational learning medium. Users are forced to respond to write their own inputs and observations. These inputs then act as "memory breadcrumbs" for you to retrace when you again come back later on. And then you can resume or update your mental models/abstractions about the topic.

I have written a comics-based essay on this topic: https://primerlabs.io/comics/memory-breadcrumbs-comics/

It took time for me to get it right, because of my perfectionism issues. There are two free courses right now: Python-I and Fundamentals of Computing.

The features of the platform are:

- Automatically generates flashcards which you can export as Anki

- Generate a personalized Book after completion

- Retrace Mode to retrace whatever you have learned

If anyone wants to try out conversational learning medium, you can use it at https://primerlabs.io/ ( No Signup Required Whatsoever).

[SquishyPanda23]

Are you sure you want to memorize it? It seems better to understand it well.

If you do want to memorize it, then some form of flashcards with spaced repetition.

If you want to understand it, keep reading and dig deeper into the topics that interest you. Also for technical stuff work through some examples.

[chelonian]

There is ample evidence to support the idea that testing oneself is a great method for increasing retention (review and meta-analysis: https://www.gwern.net/docs/spaced-repetition/2021-yang.pdf).

Also, you seem to have just read the CFA and CAIA once. If it is detail-heavy, there's no way for most mere mortals that is going to stick around for months. To really learn detailed, dry material in a way that sticks, you have to immerse yourself in it for much longer than that. Most people only retain details that are part of their work on a daily or at least monthly basis.

[efitz]

[https://en.m.wikipedia.org/wiki/Spaced_repetition Spaced Repetition] (Wikipedia)

Has everyone here has stated, Writing the information is a very effective way to reinforce your retention of it. You can make it even more effective by writing the information in the form of a flash card, and then using spaced repetition to reinforce the information until you have mastered it.

There are a lot of good flash card applications out there that use this technique; my favorite is [https://www.ankiapp.com AnkiApp]. (AnkiApp.com)

[rahimnathwani]

FYI Ankiapp isn't related to the Anki project.

[jason_slack]

I use spaced repetition for preparing for exams. It works quite well for me along with an active recall notebook that I can easily read through many times a day.

[strelka_]

I usually need to find "usable" ways of introducing the subject I'm studying in my day-to-day life.

As for finance, eg. I'd try to read Economy mags more often, and try to explain to myself just "what the actual hell" they're saying.

This method can be very challenging when you're starting on something, but by the time (two weeks) you get to know "just enough" you'll be flying through the news, and then you can get to scientific papers on the subjects that you have interest on.

For programming, my way for it is exactly the same, but without newspapers and articles: just try to approach everything in a specific mindset.

[mox111]

Readwise (paid service) does this for me.

Lots of integrations (kindle highlights, hypothes.is highlights on the web etc.), and they present your old highlights to you in the form of spaced repetition, either via email or via the smartphone app.

[rkhassen9]

Train the recall neural pathways for the scenario you envision needing the info. Active recall at intervals.

This is the only thing that really works for me.

What I have not automated is creating active recall scripts as I go....it tends to happen organically as I run through scenarios in practice sessions, eg if I want to share info verbally, then what parts do I forget, when I practice? Drill on that section, and test it out ant intervals until it's locked in. Then test at much wider intervals to maintain. (Super memo and Anki have complex algorithms, but I like to ballpark it to reduce complexity)