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Spaced repetition can allow for infinite recall
- cptcobalt 4y agoI see this argument as semi-fallacious, since it's really asking "can you recall infinite things on an infinite timescale using this method"? Sure, the math might add up, but humans are reliably fallible. I do agree, from practice, that practicing spaced repetition can increase the breadth of knowledge beyond that of "casual learning", but I've seen my brain fail on aged entries too. Nicky Case's intro to spaced repetition is pretty stellar, both as a crash course and the reasoning behind it: https://ncase.me/remember/ https://ncase.me/remember/
- jacb 4y agoMore than semi-fallacious - the math doesn't add up, because you run into the Bekenstein bound, which limits how much information you can pack into a volume.
- jerf 4y agoThis is why I don't use spaced repetition. The danger of becoming a black hole is just too high. Forgetting things is well known to be highly evolutionary advantageous, because all the critters that remember everything and turned into black holes stopped reproducing. Very dangerous stuff to play with.
- jacb 4y agoHa! Certainly none of us will get anywhere close to this bound, no matter how much time we log in Anki. But the OP asked "Would an infinitely-long-lived, but forgetful person be able to recall an infinite number of facts using this method?", and the answer is a surprising "no, you turn into a black hole".
- ben_w 4y agoSometimes even just one piece of knowledge can turn you into a black hole. It’s why nobody remembers every digit of Graham’s (phone) number. ;)
- jquery 4y agohis phone number is highly compressible though, it’s the decompression/serialization step that turns you into a black hole
- jrussino 4y agoI know we're all playing around here, but surely the answer must be that there's a limit rooted in the specific biological/chemical implementation of memory in the brain that our hypothetical "infinitely-long-lived, but forgetful person" would hit before the Bekenstein bound (probably long before) and therefore it's impossible to turn a brain into a black hole via that mechanism.
- orangepurple 4y agoThe more you learn the more you gain the ability to encode new facts with fewer "bits." Thanks to associative memory. Adults have an advantage in learning in this regard.
- makeset 4y agoTragic really how smart people know perfectly well that you shouldn’t exercise if you don’t want to accidentally turn into a grotesque muscle freak, but rarely use the same caution in brain exercise.
- LittleFishyChan 4y agoI guess I’m the extreme case then; I’ve been using SuperMemo for 16 years, every single day; originally it was to memorize foreign language vocabulary words, but has since expanded to everything I want to know. Left unchecked you’re right, you can easily become obsessed with memorizing junk knowledge and becoming like the comic book guy from the Simpson’s. But over time it has helped me learn how to “compact” complicated ideas into simple statements and more easily internalize new ideas. Since I’ve been using SuperMemo to remember concepts, metaphors and illustrations kind of just “appear” in my brain. I don’t fully understand why, I think it’s like lightning striking a place with lots of metal; you can’t force it to happen, but you can make the conditions conducive to “lightning strikes” of inspiration.
- shkkmo 4y agoThe argument is wholely fallacious and the author knows it and is just being silly. The entire argument is based on assumptions that only hold for smallish numbers of items. It we get to larger finite numbers, such as the number of possible states of a human brain, those assumptions are clearly false.
- rideontime 4y agoSincere question: is this satire?
- NotTameAntelope 4y agoHonestly yeah I think it’s a form of satire[0], which IMO takes nothing away from the joke. Satire is fun! And I think the folks taking the math seriously are probably in on the joke. [0] or whatever brand of comedy “imagine a cow approximates to an oblong sphere” is. “This is strictly satire” is not a hill I must die on.
- kelseyfrog 4y agoThis is false if memory's are stored physically in the brain. Unless there is an increase in brain volume, this process will eventually hit the Bekenstein bound. I don't care if the upper bound is "effectively infinite," that's not what the proof claimed.
- marcodiego 4y ago> "effectively infinite," This is what I have been thinking. If whatever you can remember is bigger than all experiences and lessons you could remember, then your memory is effectively infinite. I don't know if having a continuous effectively infinite memory is good or bad. As someone who play the classical guitar, having a better memory would do wonders for me.
- deleted 4y ago[deleted]
- vntok 4y ago> I don't care if the upper bound is "effectively infinite," that's not what the proof claimed. Very interesting. Do you typically process all claims as literally as you just did for this one, notably when you're interacting with people outside of the Internet? In which case, do most people react positively to your behaviour, or do they get annoyed because "you know what I meant"?
- kelseyfrog 4y agoInternet "well actually," culture made me this way. I preempt rebuttals I'm not interested in.
- _dain_ 4y agoI don't think you're actually a real frog.
- kelseyfrog 4y ago
- cortesoft 4y agoThis 'proof' seems a little suspect. It assumes that the rules they have discovered hold for all situations. Even if they have tested a large number of facts to remember, there is no reason to believe their isn't some threshold where it doesn't hold anymore. Also, they seem to be holding this learning technique like it is a mathematical fact of the universe. I am not an expert, but nothing in the human brain works that consistently. I can't imagine every single person in the world can learn equally well with this technique. Although this is likely some form of satire, because there is no way anyone could seriously think the brain works like this.
- dinobones 4y agoTLDR I know how to use latex and took calc 2, I want to look smart on the internet.
- Silverback_VII 4y agothere are only a limited amount of things you can memorize because your lifetime is also limited. Piotr Wozniak the creator of supermemo, the first spaced repetition program, talks about it on his site: https://supermemo.guru/wiki/How_much_knowledge_can_human_brain_hold https://supermemo.guru/wiki/How_much_knowledge_can_human_bra... this guy is a genius in my opinion.
- orangepurple 4y agoI am in no way affiliated with the guy but you should read the seminal papers published by John R. Anderson. This guy has been in this game since the 70s Carnegie Mellon University Professor of Psychology and Computer Science http://act-r.psy.cmu.edu/peoplepages/ja/ http://act-r.psy.cmu.edu/peoplepages/ja/
- dls2016 4y agoI was anti-memorization until I went back to graduate school for mathematics. I had forgotten (or never learned) a lot of things needed to pass qualifying exams. At some point I ran across the spaced repetition idea (maybe from the Wired SuperMemo article [0]) and I gave it a try. I ended up using it to memorize large portions of baby Rudin and Munkres' Topology, as well as some algebra and a bunch of qualifying exam questions. The qualifying exams were difficult until I reached some "critical mass" of knowledge. Then I could regurgitate proofs and even attack novel problems easily. There's an analogy here somewhere to the "leetcode" style of software engineer interview. On one hand qualifying exams and leetcode questions are a stupid gatekeeping mechanism, but on the other hand the best researchers/engineers I know have a huge number of facts and examples memorized and ready at their fingertips. I didn't think I needed to do so, but perhaps there is something to suffering through the rote memorization phase to make what comes next that much easier. [0] https://www.wired.com/2008/04/ff-wozniak/ https://www.wired.com/2008/04/ff-wozniak/
- rg111 4y agoHi, can you please show me some of your cards? Do you create cards with full proofs or do you write parts of proof? Or do you write down definitions? Can you please give me an idea how you used spaced repeatition for grad school math? Thanks.
- Silverback_VII 4y agoMemorization is powerful only if you memorize the right stuff like Machiavelli's Prince instead of a phone book. Incremental reading (supermemo 18) to dissect books is even better I think.
- kazinator 4y agoI remember the exact point in my life when I realized how much difference rote memorization makes. I had the opportunity to write some MC68000 assembly code, at a time which was not too long after having written a complete emulator for it in C. Writing the emulator required me becoming familiar with every single instruction in all of its nuances, and exactly what they all do. So, having that behind me, I sat down to write this code and it was like wow ... I could just spew the code without having to look anything up. It was so easy!
- dhosek 4y agoIt kind of reminds me of what I used to say about 9-ball pool: You can play with an infinite number of players but not everyone will get a turn.
- kazinator 4y agoIt's cute math, but doesn't take into account the inexplicable differences between the retention of seemingly similar facts. Some items stick very well, whereas others suffer from lapses. In my Ankid ecks, I have items that have 10+ year intervals. And some, which were introduced at around the same time as those, which have intervals in months, beaten down by lapses. Anyone who thinks that some simple math leads to infinite recall has not suddenly lapsed on a card whose interval had reached 7 years.
- orangepurple 4y agoI don't recommend allowing Anki items to have an interval of over one year because the crude SM-2 algorithm does not capture the per-item effect of exponential decay in memory. Multiplying interval lengths by per-item ease factors is suboptimal and not the same. Unlike, for instance, ACT-R, which unfortunately has no good publicly available user interface. A good implementation of a neural memory fact model will track strengths of associative memories in addition to the per-item exponential forgetting curve. Keep the Anki intervals capped at one year until something better comes along.
- kazinator 4y agoProblem is it seems you're then throwing under the bus all those items you recall perfectly well that have 6+ year intervals, which don't require yearly review. Arguably, you could just retire those; but then sometimes they lapse, as I noted: how do you decide what to retire?
- orangepurple 4y agoBuild a knowledge graph of associative memories, measure their strength, and prune clusters with excessive memory strength
- barking_biscuit 4y agoI mean sure. The trouble is in order to keep the review time per day fixed you need to vary the rate at which you introduce new facts, and as time goes on the interval between when you can afford to introduce new facts will grow to be infinite. The model also doesn't account for how you feel about doing this activity. This includes the pain of not doing reviews for several days and then having to catch up. The probability you eventually throw in the towel is also a function of how useful you're finding the activity, which in this case since we've opted to keep the per-day study time as fixed will likely be when the interval that you are required to wait before you can add a new fact becomes so large you are routinely bothered by occurrences where you encounter a fact you wanted to put into your SRS but didn't have the bandwidth to. Source: input 35 new vocab a day into Anki while learning Japanese a decade ago and grew my vocab deck to 18000+ cards. Reviews would take several hours a day, and at one point I stopped adding new words to try and wait for the daily review load to go down. When it never did despite this, I just deleted the entire thing and say fuck it.
- martindbp 4y agoYeah, I've got 9000 reviews waiting for me in my old Chinese Anki deck, at some point you always fall off the wagon. I've changed my mind several times on SRS going back and forth, and my conclusion is that, for language, I think it's better to split your time with 90% on consuming meaningful input and 10% SRS, because learning in context with real content that you're interested in allows you to encode your memories much more efficiently. The problem with pairing available SRS systems with consuming real content is that they don't take into account "natural" repetitions, e.g. when you encountered a word in a movie outside the SRS, so they tend to underestimate how well you know a word. But also since "natural" repetitions are baked into the SRS model via parameters that fit the "average", it also tends to overestimate your knowledge of a lot of other items. Combined, you just have a very inefficient schedule that takes too much of your time for too little gain
- orangepurple 4y agoA prioritized queue of stuff to learn may be a better solution than staring at "over 9000" things to review. Such a queue would mean you simply bite off as much as you can chew every day and don't perpetually fall behind, assuming the priority queue has a small degree of randomness and is recomputed daily based on the decay rate of all modeled facts. Do you agree?
- tiborsaas 4y agoFinally, a mathematical proof to take as many pictures as possible is a good idea :)
- tpoacher 4y agoI'm a fan of spaced repetition too and have incorporated Anki in my life in more ways than simple memorization. But calling it "infinite recall" is a bit misleading. Improved long-term retention at the cost of minimal unintrusive prompting is probably closer.
- comfypotato 4y agoThe article is a joke proving how an immortal person could get infinite recall with spaced repetition.
- tpoacher 4y agoThat's not how I read it. And in any case, that is a common attitude/misconception about spaced repetition, which disillusions many people after they realise they still need to put the effort in to make it work, so it's worth pointing out.
- cehrlich 4y agoI've been using Anki for language learning and it's a superpower. After just over two years I passed an exam that requires a passive vocabulary of about 10,000 words. Other people who grinded harder than me have managed it even faster, some in under a year. However one big mistake people make is to think an SRS helps you learn. That's not true. It helps you not forget things you've already learned. You still need some real world interaction with the material.
- borroka 4y ago>> It helps you not forget things you've already learned. The argument is quite weak when we discuss learning words in a foreign language. You learn that lunch is "almuerzo" in Spanish, but is it learning or just memorization/association? To me the lines are blurred, even at first sight of the word. I used Anki myself to learn foreign languages and it is tremendously effective for words and short sentences too. I use it also for words in my mother tongue, and it made be much more articulate than I used to be.
- _dain_ 4y ago>You learn that lunch is "almuerzo" in Spanish, but is it learning or just memorization/association? To me the lines are blurred, even at first sight of the word. I think there's a difference. "Almuerzo" -> "al muerzo", I know "al" means "the", from Arabic, I look up the etymology, the "muerzo" is from Latin "morsus", from which we get "morsel" in English. Mnemonic: "the morsel". Then I can guess that the form of the verb is almorzar, which is indeed the case. Even learning a simple word embeds and thickens a web of associations in one's mind. SRS strengthens this, makes it scale better.
- pessimizer 4y agoThere's a guy who did a book like this: http://yong321.freeshell.org/lsw/ http://yong321.freeshell.org/lsw/ preview: https://www.google.com/books/edition/Learning_Spanish_Words_Through_Etymology/OYSZCwAAQBAJ?hl=en&gbpv=1&dq=Learning+Spanish+Words+Through+Etymology+and+Mnemonics&printsec=frontcover https://www.google.com/books/edition/Learning_Spanish_Words_... It's just a bunch of vocabulary paired with etymology notes and observations/sounds-likes to make the vocabulary memorable.
- mikkergp 4y agoI know this is just a joke, but there was an interesting Radiolab on memory and forgetting. It posited that forgetting is an active process, and analysis a person who was disabled in such a way that their forgetting process didn't work led to some very undesirable outcomes: https://radiolab.org/episodes/91569-memory-and-forgetting https://radiolab.org/episodes/91569-memory-and-forgetting
- buscoquadnary 4y agoI'll just throw out I am a big fan of spaced repetition I highly recommend it to everyone. For those complaining about "infinite recall" you aren't wrong, the pioneer of this movement Piotr Wozniak, even has an article on his wiki (https://supermemo.guru/wiki/Piotr_Wozniak https://supermemo.guru/wiki/Piotr_Wozniak) about how the upper bound of languages you can learn fluently in a lifetime is probably somewhere near 5. But the point isn't to remember everything forever, the purpose is to help you learn better. My flow right now for learning things is. 1. Find sources copy and paste large swathes of revelevant text and images. 2. Re-read the copy and pasted text and create a detailed summary of it in my own words. 3. Come back a few hours or day later and summarize the summary. 4. Use this as the basis for cards to load into Anki. It isn't about building a massive repository of facts, and you can do plenty with just steps 1-3 without ever using Spaced Repetition, but the reason I fell in love with spaced repetition and have jumped on it so heavily is that I've done steps 1-3 with a lot of information and subjects, and over time have forgotten all but the most basic things about them. This makes me feel as if part of my time or life was wasted, because if I have to revist something again latter like Sorting Algorithms it feels like starting over. Whereas things I have started to use spaced repetition with, I retain the fundamentals the "outline" of the subject for much longer, and if I have to revisit it I feel much more familiar because to paraphrase Piotr Wozniak. The things we remember well are things that are well located/connected within our knowledge tree. For those IT people out there as well the other thing spaced repetition and especially Anki is super useful for is learning how to use your tools more effectively because it helps you to remember those features and tricks that you don't use often but super speed things up. For example I used grep for a long time, I often found myself having to hit up the man page, or the DDG if I needed to do something unusual, or more often I'd end up trying to cobble something together with the tools I had. I reviewed a "most useful flags" in grep page a few months back and decided to Ankify it. I am now an order of magnitude more proficient with grep because I can quickly recall the flag or option I need to provide to do something wonky with it when I need to, simply because I remember a relatively obscure feature, that I don't use often and would've forgotten otherwise. Finally in conclusion The 4 states that made up the Austro-Hungarian Empire were Boznia-Herzgovania, Croatia-Slavonia, The Kingdom of Hungry and Cieslenthia. Because sometimes memorizing one or two random facts just makes life more interesting.
- krychu 4y agoShameless plug for a little tool I wrote to learn by repetition on the command line: https://github.com/krychu/lrn https://github.com/krychu/lrn I use it whenever I have a few minutes of downtime, no fancy state persistence between sessions.
- ggm 4y agoI frequently have arguments with competent mathematicians about the role of rote learning in arithmetic. I think when you move "beyond" arithmetic, you can also forget how important number recall is, in being able to manipulate numeric symbols fluently according to the rules of arithmetic. Include base (hex, binary) and .. its getting worse. Numeracy, numerical literacy and fluency, understanding both the symbol set, and its behaviour in rules of arithmetic, needs to be a given, to talk cogently about numbers. Simply teaching all kids the 12x tables, and how to handle the arithmetic of change giving at a till from the specific units of coin and note available, how to run a total in their head, how to calculate % will be life skills which might literally save their job. And its foundation is recall, and rote learning. Not everyone is heading to 3rd order differential analysis.
- tastysandwich 4y agoBased on my own experience, a caveat is that you need to be applying what you're learning outside of flashcards. Otherwise, it's like your brain has different memory banks for different contexts, and you'll remember everything when using your flashcards, but a real-world scenario will come up and you'll forget. I went from zero Japanese to JLPT N2 in just a few years and I attribute a great deal of that to Anki. However, I was also frequently talking in Japanese, and reading/writing in Japanese. I was constantly using what I was learning. Maybe an analogy is, Anki is like steroids, but you still need to go to the gym. :P I don't study Japanese at all anymore and I have very little exposure to the language. But I still do my flashcards. I've noticed my recall is excellent when doing the flashcards, but if I see some Japanese written on a billboard, or think to myself "how do I say this again...", I struggle to recall even things that are in my flashcard packs.
- bayesian_horse 4y agoIn my opinion the memorization (with whatever method) gets you started. There is no good replacement, and in that phase any other learning activities really aren't as important. Only when memorization has laid the basic foundation does it make sense to spend more time to read and write in the new language. In my opinion reading is the most efficient activity at higher levels.
- wodenokoto 4y agoI disagree. Even at the early stages you should be reading simple sentences with words you just learned and you should be creating sentences with structures you just learned.
- bayesian_horse 4y agoI didn't say you shouldn't read simple sentences or do other activities. Variety is useful. I said early on the most efficient use of your time is memorization of words and maybe grammar. Duolingo does that well, in my opinion. It doesn't do the usual flashcard stuff, but it does favor repetition and you can practice speaking and listening from the first time.
- n8henrie 4y agoNot to detract, but there was an article on SRS that I think I came across on HN about 2-3 months ago (though I guess may have been Reddit); I've been struggling to find it for the last month or so. It was a fairly long article, probably a 20-30 minute read, dark background (though I guess this may have been dynamic since I was reading at night), with a broad overview of SRS, several studies cited, and a personal anecdote from someone with somewhere around 10k cards that the author reviewed daily. I wish I could remember more details. I've combed through my browser history in all browsers (desktop and mobile) and have tried a few site-specific timeframe-limited searches with no luck. Does this article sound familiar to anyone? It was a good read and somehow I failed to pinboard it.
- JoshuaLelon 4y agoIs it this one? https://www.gwern.net/Spaced-repetition https://www.gwern.net/Spaced-repetition
- gwern 4y agoBased on the mention of auto-dark-mode, probably. We put some effort into thinking about how to do dark mode right and integrate with system settings - your usual website hack of an invert toggle is wrong, but the correct auto/light/dark tri-state toggle is not obvious.
- n8henrie 4y agoI'll have to look at the strategy you took. Thanks for the article! I now also remember the mention of Mnemosyne, which was the first SRS app I ever used (got me through medical school!). Now using RepetitionsApp x years.
- n8henrie 4y agoThat's the one, thank you so much! Skimming it quickly, I now remember the Haskell. Funny to have forgotten how to find an article on a memorization technique.
- myth_drannon 4y agoHow can I apply that to leetcode interview preparation?
- gwern 4y agoForgetting isn't a power-law according to Wozniak, but an exponential: https://supermemo.guru/wiki/Exponential_nature_of_forgetting https://supermemo.guru/wiki/Exponential_nature_of_forgetting The power-law is just averaging over that: https://supermemo.guru/wiki/Exponential_nature_of_forgetting#Power_law_emerges_in_superposition_of_exponential_forgetting_curves https://supermemo.guru/wiki/Exponential_nature_of_forgetting...
- bayesian_horse 4y agoThis is obviously a joke. But people get spaced repetition wrong. Most people think you need a spaced-repetition schedule for long term memory of facts. You really don't. The only proposition of spaced repetition is that you spend less time studying when using this schedule than with a more dense repetition schedule, if both lead to the same long term memory effect. Another schedule might be to review your complete vocabulary list every day. This will also lead you to long term memory, eventually. Earlier probably (in terms of calendar time). But you'd spend more hands-on-time studying. However, you'd much prefer the former method over the latter when preparing for an exam on a specific date. Also: formal methods of managing the schedule aren't really necessary. Reading in a foreign language counts as repetition of the words. Exposure to the language and the vocabulary counts, for example what Duolingo does with its various activities is partly spaced repetition, but less formally so.
- yanis_t 4y ago
- chadlavi 4y agoAnyone recommend an iOS app for this? There are a ton of kinda sketchy looking ones in the App Store.
- examplary_cable 4y agoI have read a lot of comments that appear to be a modification of "I used anki but the accumulation made me drop it". If you're interested, I've worked in a Spaced Repetition Algorithm where they is no card accumulation, you review whenever you feel like. In order to maximize pleasure. In the future I'll also configure it to give you subject you "feel" like reviewing at the moment, since pleasure is also associated with memory. https://github.com/ilse-langnar/notebook https://github.com/ilse-langnar/notebook