Edit: Hey guys! This has proved to be one of the most popular articles on the site, so I’ve created a supplemental download on the 5 biggest Anki mistakes people make and how to avoid them. Enter your email below (or on any of the forms scattered around the site), and I’ll send it to you, along with ~2 emails per week on research backed techniques for achieving anything.

Here’s the form:

 

If you don’t know what Anki or spaced repetition is, start by reading gwern’s excellent introduction.

This month, I created my ten thousandth virtual flashcard. When I started using Anki, I worried that I’d do the wrong thing, but decided that the only way to acquire Anki expertise was to make a lot of mistakes.

Here’s how my Anki usage has evolved.

Why questions

Cards that answer the question “Why?” are more valuable than factual cards. (See also this post.) It’s easy to memorize that QuickSort has a lower bound of O(n lg n), but better to know why it has such a lower bound, and even better still to understand why comparison-based sorts can’t be faster than O(n lg n).

Of course, it’s best to know all of these.

My emerging perspective here is that it’s important to understand all the context of an idea to really know it. How it emerged, how to invent it, what it’s for, and so on.

Images

My original Anki decks were all words. Now, I lean on images as heavily as possible. I find, at least for my sort of mind, that most of understanding something is learning to visualize and manipulate it mentally. Google image search is one of my first stops. In a pinch, I also make crude drawings of my own. As long as it captures the main idea, it’ll do:

As an unintended consequence, my thought itself has shifted towards more imagery. The repetition makes an image representation of a concept more available mentally than its equivalent in words.

Connections

The biggest problem with Anki is the tendency for cards to become disconnected, so that a lot of knowledge is only available with the right cue and, even then, it’s a sort of impoverished thing.

I’m not aware of any silver bullet for this problem, but I now construct more cards that enforce links between knowledge. I might ask, “How is this concept different from that concept?” Or how a concept explains something from my personal life, or what an idea is reminiscent of.

The main limitation here is the general unavailability of a piece of information. With the right cue, I can recall it, but it’s not as if I can just sit down and brain dump every single one of my memories.

Mnemonics, at least the method of loci, are a bit better in this regard, as I can think myself to a place if I need to retrieve something.

Single deck

Currently, I have decks organized by topic and subtopic. However, I now think this is backwards. Given Hebbian learning — neurons that fire together wire together — I’m convinced that mixing everything is superior.

Take the production of insight, for instance. I find that insight often arises when two ideas that have been recently activated in memory collide and I think, “Oh, wait, that’s related to that.”

If everything is carefully partitioned, you limit opportunities for this serendipity. Topic organization says “ideas about computer science don’t belong with those about economics,” except applying ideas across disciplines is precisely where the insights are likely to be most fertile.

Two-way connections

Here’s a mistake I’ve made a couple of times. You’ll be reading a text and it’ll define something, like the Martin-Löf-Chaitin thesis, and you’ll create a card saying, “What’s the Martin-Löf-Chaitin thesis?”

Then, sometime in your life, you’ll be sitting and thinking, “Hey, what’s that mathematical theory of randomness called?” and you won’t know, because you didn’t make a card like that, and your mind only learned the connection one way.

This has also happened with cuckoo hashing and I’m sure other things too, so now I make more of an effort to learn something forwards and backwards, like “What’s cuckoo hashing?” and “What’s the name of that probabilistic version of hashing?”

In general, poor models of how memory and mind work hinder Anki effectiveness. You might think, hey, knowing something is all there is to knowing. Wrong. A lot of knowing is creating different cues and representations of that knowledge so that you can recall it when needed.

A great deal of an effective knowledge base is engineering it so that it’ll be useful in the sort of situations where you expect to apply it.

Adding whatever

My philosophy when I started using Anki was to add whatever, to just adopt a trifling barrier to entry. I didn’t worry about whether a fact is useful or not or anything like that. If something appealed to me, I’d add it.

This core is remains. The main change this philosophy has undergone is to shift away from setting a specific study time and making cards during that study time. Instead, I add anything interesting, regardless of when it happens, and random connections and insight that occur to me throughout the day.

For example, each morning I go through my RSS reader and check the news for the day. Whenever I come across something interesting or insightful, I add it.

Or here’s a common hangup people have, and that I had, when starting with spaced repetition. It’s the question, “What ought I memorize?” and people think, well, maybe the presidents or something, because that’s what they’ve associated memorization with.

It’s the wrong question. Ask “What’s interesting?” and start ankifying that.

People also really like it when you can recall minutia about them, too, which is sort of fun. If someone mentions their favorite type of cheese, or a pet’s name, make it into an Anki card. It’s like free social points. Memorizing birthdays works.

Thoughts on the value of Anki

I remain, more than a year later, enthusiastic about Anki. The honeymoon period is over and I still think it’s awesome.

Anki-powered studying has become my new normal. Whenever I regress to trying to memorize something spontaneously, without software assistance, like command line flags or some bit of HTML, it’s frustrating. It feels like something is wrong, like it ought to be so much easier, because with Anki it is.

Which is not to say that Anki is a panacea. Just as it’s a good idea to diversify your stock portfolio, it’s a good idea to diversify learning methods.

Further Reading

• I’ve written before about the importance of “Why?” questions, on structuring knowledge, and on different modes of thinking about mathematics (but which are broadly applicable).

You take the blue pill, the story ends. You wake up in your bed and believe whatever you want to believe. You take the red pill, you stay in wonderland, and I show you how deep the rabbit hole goes
—Morpheus, The Matrix

Ted is 23, fictional, and one night stays up late browsing the web. He starts on Wikipedia, finds himself reading the page on the 9/11 terrorist attacks, follows the links to conspiracy theorists, and eventually lands on YouTube. He watches videos all night. His brain stews in the information.

The sun rises. He’s convinced. 9/11 was an inside job.

But Ted has a problem. If 9/11 was an inside job and anyone with an internet connection can find out the truth, why are so few people believers? It’s unlikely that Ted just happens to be one of the select few that has figured out the truth. He needs some sort of justification. In general, weird beliefs are wrong beliefs, so why isn’t this weird belief wrong?

Ted stumbles around for a while, grasping at nothing, until… Eureka! No one else realizes the truth, he thinks, because the truth is so horrible. Our own government was in on it. Ted figures that he can see the truth because it’s his nature not to shy away from the painful things in life. He’s a stoic, don’t-you-know.

Except 9/11 wasn’t an inside job. Ted’s belief system has been poisoned.

Swallowing the Red Pill

I’ve heard this phenomenon described by adherents of outside-normal beliefs as “swallowing the red pill” — like when Neo accepts Morpheus’s offer and realizes he’s been living inside of the matrix.

It’s rhetoric. Sure, there are terrible truths about human existence, but:

• Something that is painful to think is not true by virtue of being painful to think.
• Too much emphasis on the negative aspects of something blinds people to the complexities of that something.

Regarding my second point, consider the worst of the pick-up movement. They took something with a kernel of truth — that women find
dominance behavior attractive — and expanded it into a philosophy.

The trouble with that, of course, is that it misses out on all the complexity of relationships — you know, the whole reason why
you might want a significant other in the first place. Social interaction isn’t zero sum. Both parties can benefit more by cooperating than they would otherwise.

All of this is to say: If you stumble on some group of people that claim to have recognized a terrible truth that no one else can bear, beware nonsense.

There are two types of writer — the snobs and the engineers. The engineers believe that crafting the right sentence is a rule-based affair. “Be brief. Avoid adverbs.”

The snob turns up his nose at rules. Rules, he says, are for the amateur. The English language is not about rules — great writers break them all, and those who preach about rules don’t even follow their own.

I don’t like the snobs. I mean, they have a point. In language, there are no absolutes — well, probably. But rules are useful. I suspect the real reason that snobs are so against rules is because it’s an opportunity for them to signal their sophistication. “Rules? Ick. Rules are training wheels and not for the likes of one as fine a writer as I.”

Adherents of snob theory ought to try programming. If I’m making ten mistakes an hour, it’s a good day. I’ll use any crutch available and I’ll be proud that I do. The world is a complex place. We need tools to help us tame that complexity.

Engineering in the art of writing

Spell Check

I’ve dominated more than one spelling bee in my day and used to believe that I didn’t need to spell check my work. What a poor, deluded fool I was! (I still am, but less and less and less.)

Now I spell check everything I write. I’d estimate that I have an error rate of about one or two for every 250 words. It takes 30 seconds to run a post through spell check after I write it, which is enough to eradicate the errors.

Weasel Words

Matt Might, an assistant professor at the University of Utah, wrote a set of shell scripts to help PhD students improve their writing. He focused on eliminating weasel words and passive voice. His scripts have since been ported to emacs in the form of writegood-mode.

Some examples of weasel words:
* many
* extremely
* interestingly
* surprisingly

A 2009 study analyzed the usage of the “weasel words” tag on Wikipedia and found that they fell in three broad categories:

• Handwavy use of proportion that doesn’t answer the question “How many?” (“Some people”, “Experts”, “Many”)
• Use of the passive voice.
• Adverbs, e.g. often, probably.

Such sentences can be rewritten by substituting more specific language. Wikipedia offers this example: “The Yankees are one of the greatest baseball teams in history,” can be rewritten as “The New York Yankees have won 26 World Series championships—almost three times as many as any other team.”

The principle behind this, and the “Show, don’t tell” rule so often trotted out in this sort of discussions, is to eliminate reliance on the author. If I tell you that a problem is important, you can either trust of ignore me, while if I reveal my evidence, you get to “use your own free will.”

Clichés

Never use a metaphor, simile, or other figure of speech which you are used to seeing in print.
—George Orwell, “Politics and the English Language”

Consider two phrases:

• No one in his right mind would reject reductionism.
• No one in her left brain would reject reductionism.

The second comes to me by way of Doug Hofstadter and is, I think, the more compelling of the two. A phrase, when overused, loses all of its punch and becomes boring.

Examples:

• Hope against hope.
• Ignorance is bliss.
• Matter of life and death.

My fork of writegood-mode supports highlighting cliched phrases. For those who are not members of the emacs cabal, there is also an online cliche finder.

Grammar Checking

There are more possible errors than spelling mistakes, which is where automated grammar checkers come in. They’re not as good as human feedback, but they’re convenient and catch problems that you otherwise might not.

I ran a recent post through the open source LanguageTool and it managed to spot that I’d used “free reign,” when it should be “free rein” — a mistake subtle enough that I would never have noticed it. Hell, I thought rein and reign were spelled in the same way.

For emacs users, you can install LanguageTool and langtool-mode to check your writing from the convenience of your text editor. Non-emacs users have the option of installing and checking from the command line, or using the online version.

Readability

The average American reads at between a 7th and 8th grade level. If your prose is too complex, you’re alienating a fair chunk of potential readers.

According to Wikipedia’s article on readability, TV Guide and Readers Digest, the two publications with the largest circulation, are written at a 9th-grade level, while the most popular novels are written at a 7th-grade level. A 1947 experiment by Wallaces’ Farmer — a magazine — found that reducing an article from a 9th to 6th grade reading level increased readership by 43%.

The GNU project ships style — a command line tool that checks the reading level of a piece of writing. Running this entire blog through it returns a reading level of 8, according to the Flesh-Kincaid formula. The formula correlates 0.91 with reading comprehension.

For emacs users, there’s artbollocks-mode, which has a built-in readability test and duplicates some of the features of writegood-mode. For non emacs users, there’s GNU style and this online tool.

A Writing Checklist

In 2001, Dr. Peter Provonost — who specializes in critical care at Johns Hopkins — put together a checklist of the obvious things that doctors need to do before treating a patient: hand-washing, wear gloves, clean the patient’s skin before inserting a needle, that sort of thing. These are not super tricky, only-clever-people-know steps. Everyone is supposed to do them, everyone knows, but sometimes people forget.

After implementing the checklist, infections in the ICU dropped from 11 percent to zero — saving 8 lives and 2 million dollars. Consequently, the hospital implemented still more checklists — reducing the average ICU stay by half and saving 21 lives.

A 2009 study duplicated this success in 8 other hospitals.

Still not convinced? See my post on the effectiveness of checklists.

I have my own checklist for writing:

• Make sure all my links are to high-quality domains and treatments.
• Are links to Further Reading resources.
• Add links to other relevant posts I’ve written.
• Add images.
• Check for broken links.
• Add more relevant examples if possible, especially personal ones.
• Humanize the writing.
• Remove unoriginal metaphors or examples.
• Remove hedged phrases, weasel words.
• Switch passive phrases to active.
• Remove any foreign phrases, scientific words, or jargon that aren’t necessary.
• Read out loud and check for flow.
• Remove any criticism of other people.
• Remove cliches.
• Search for “ly” words and remove them.
• Search for exclamation marks and semi-colons and remove them.
• Strip needless words.
• Check reading level.
• Give it a good, googleable, and sensational title.
• Add a summary.
• Write google description.
• Bold the important parts.
• Have other people read it and get their reaction.
• Spell check.
• Grammar check.
• Make sure it renders properly.

Further Reading

• If you’re interested in improving your writing ability, check out my post on expertise.
• For tips on writing, there’s Orwell’s “Politics and the English Language.”

Yesterday, I saw someone spin this very plausible theory about why it’s so repellent when someone brags about their IQ on the internet. (For the record, each time I’ve been tested I’ve been told that I’m “off the charts” and “almost certainly the smartest man that has ever lived” — their words, not mine.)

It went something like, “Well, people who brag about their IQ on the internet are narcissists, who have nothing worth bragging about except their intelligence. That’s why they’re so off-putting.”

Except narcissts aren’t off-putting. Not at first, anyways. According to Back et al., “Narcissism leads to popularity at first sight.” Holtzman and Strube confirms, “A meta-analysis (N > 1000) reveals a small but reliable positive narcissism–attractiveness correlation that approaches the largest known personality–attractiveness correlations.”

The real reason it’s off putting? It’s probably false. The probability that someone is wrong about their IQ is, I’d estimate, at least one in four. They might have taken some fake online test, “misremember” their score, taken it at the age of seven, that sort of thing. Or, you know, they could be lying.

The distribution of pathological liars in the general population is not clear. Wikipedia suggests 1 in 1000 among repeat juvenile offenders, but given the prevalence of other mental illnesses — psychopathy at 1 percent and depression at 7 percent — I expect that’s a lower bound.

So, I guess what I’m saying is, these days, when I come across an unbelievable story on the internet, I try not to believe it.

Heuristic: Focus on concrete categories when generating ideas.

The brain is a stupid lump of fat. I sometimes say to it, “Brain, what ought I write about today?” and Brain goes, “Dunno, boss,” and then shuts off — starts humming some melody and wondering if anything has been posted to The n-Category Cafe lately. It’s like I’m on vacation in the Sahara, and Brain is driving, and I get out of the car to pee, and then Brain just takes off, leaving me twice deserted.

Sometimes I wait, thinking that Brain is running some sort of process, and if I just leave it alone for a bit, it will come up with something — as if Brain is running OS X and after I ask him for an idea that infernal loading beach ball pops up.

Except when I come back to Brain five or ten minutes later and go, “Hey, come up with any ideas yet?” Brain says, “Ideas? What ideas?” and looks at me sorta confused, like he’s not sure how he got here or why.

Or sometimes I sit and try to “let the thoughts flow.” Except instead of flowing its more along the lines of me switching on the faucet and hearing this terrible, mechanical screeching noise, followed by rust colored sludge — certainly nothing fit for human consumption, not drinkable or readable. This usually triggers a reflection on the fact that brains are just stupid lumps of fat, followed by despair and deletion.

That’s the beautiful reality of the creative process.

The Power of Narrowing

Given that any point in time, a person probably has at least one thing worth saying somewhere in their head, the trouble is finding it. That’s the issue with just asking Brain, “What should I write about?” Brain can’t find anything without a clue.

There is a passage from the book Zen and the Art of Motorcycle Maintenance where a student tries to write an essay on The United States. It comes due. The student misses the deadline. “Couldn’t think of anything,” she explains. The narrator tells her, “Narrow it down to the front of one building on the main street of Bozeman. The Opera House. Start with the upper left-hand brick.”

I reinvented this technique a few minutes ago when I realized that it’s a whole lot easier to write about a category like “thumbs” than a category like “anything.” The restriction, in this case, makes the problem easier.

But what if you don’t have any category at all — not even thumbs? Try generating one at random, or generate two and ask “What do these have in common?”

The first day of September 1993 was the beginning of an eternal September, a calendar month whose days stretched to infinity. Prior to this infamous day, there would be an influx of noobs onto Usenet each September. These were the arriving college freshman. They were not legion. They were few enough that they could be corralled and assimilated by Usenet veterans.

September 1993, however, was different. It was the day the gates of hell were thrown open and never-ending torrent of demonspawn descended on Usenet — like locusts, they devoured the community.

These locusts were AOL users. In September of 1993, the company granted Usenet access to their entire user base, which triggered an unending deluge of noobs into the Usenet community. Thus began the September that never ended.

Community Decay Over Time

There’s a website dedicated to documenting terrible YouTube comments. Its tag line is, “The aim of this website is to document and preserve the most retarded YouTube comments, so that people a hundred years from now can look back and take solace in the fact that the authors of these stupid comments have all since died.” The dude running the website even posts an analysis of why each comment is awful. He’s doing God’s work.

YouTube’s awfulness is so infamous that there’s even a section on Wikipedia documenting it.

Or let’s consider Reddit as an example. Most Redditors agree that the default subreddits are awful, with r/funny, r/atheism and r/politics being the worst offenders. What do these have in common? They’re enormous — r/funny has more than 5 million subscribers.

If Redditors were one of those dolls where you pull a string and the doll repeats a fixed number of phrases, one of those phrases would be, “The default subreddits are terrible — stick to the smaller subreddits.”

We have this dichotomy, then, where the larger the subreddit, the more it sucks, and YouTube, one of the largest sites on the web, is horrendous. This suggests that the larger an online community, the worse it is.

The natural extension: beyond a certain threshold, adding more users reduces site quality.

The Trouble With Large Communities

Why do online communities get worse as they grow? What’s going on?

Consider the vampire bat. At night, it ventures from its cave, along with thousands of others of bats, and goes on the hunt. The vampire bat — like some sort of comic-book villain — has evolved a special brain region that enables the detection of hot spots on animals (usually goats, its favorite food). It’s a sort of infrared vision.

The bat must feed every two nights, but doesn’t always manage to find a goat. Instead, it often has to rely on the charity of other bats, who share blood after a successful hunt. The bat then pays this forward — sharing blood with those bats when they’re hungry.

As it turns out, bats are pretty decent game theorists. The hunting-sharing cycle is sorta like an iterated prisoner’s dilemma. If everyone shares, we’re all well off, and if everyone is selfish, a lot of good bats will starve, but if everyone else shares except me, great, since I get gallons of blood. To enforce cooperation, the bats implement a tit-for-tat strategy — if you share with me, I’ll share with you next time. This, plus a friendliness clause — sharing with unknown bats — is tit for tat.

Such a strategy breaks down when the share-or-not-share decision is not iterated. In a single shot game, prisoners defect — all the bats will be selfish. For blood sharing among bats to occur, they must frequently interact with bats they know.

Online communities are just like vampire bats sharing blood. I’m nice to my friends, to people I know, because I expect to see them again. That’s sorta what being my friend means. I like you, so I’ll be nice to you, and maybe that feeling of liking is evolution’s way of nudging me with “Hey, you’re going to see this person again. Cooperate!”

I’m not nearly as nice to strangers as I am to people I know. It’s the human condition. Those who claim to treat all beings equally are as naive as a child who tries to catch a rainbow and wear it as a coat.

There is no reason to trust people you will not interact with again in the future. There’s no incentive not to defect. At the end of my last relationship, our interactions became significantly less pleasant as it became more obvious that it was over — I would not have to deal with this person in the future, so why bother going through the motions of kindness?

That’s what happens in large internet communities. The probability that I will interact with any one user ever again on a site like YouTube tends toward zero. I have no real incentive to be polite or to put much effort into anything I say. Even my reputation will remain intact — who’s going to witness it?

In a smaller community, the opposite is true of the incentive structure. I will have to deal with this person again in the future and the stable set of regulars will probably see whatever it is that I do, coloring their opinion of me. Thus, I ought to act kindly and make an effort.

This kindness and effort, these are not calculated responses, not always. Much of it happens outside of conscious deliberation. The same cognitive hardware that evolved to deal with small tribes in the ancestral environment is repurposed for online discussion, and this manifests as emotion and nonconscious behavior — I like people that I see a lot and this pushes me to be more charitable. Or I feel more empathy towards regulars in a community, which affects my actions. And so on.

In summary, then:

• Communities decay as they grow larger.
• The development of trust and kindness between two people depends on the probability that they will interact in the future.
• When communities grow to a certain size, people no longer expect to interact in the future, and thus are more likely to defect — to be petty, mean, aggressive, and to put little effort into their contributions.

Further Reading

• A May 2014 study finds that a downvote mechanism negatively impacts online communities. The paper even explicitly mentions tit-for-tat — users that receive upvotes give out more upvotes, while downvotes beget downvotes.

Meditation: If there are true things that no one is allowed to say, how will you know them?

Where there are humans,
You’ll find flies,
And Buddhas.

—Kobayashi Issa

Friend, I have a confession. I like 4chan. Whenever I see someone call 4chan the cesspool of the internet or disgusting or whatever, I shake with excitement. I’ve found the King of Fools! At long last, I can kill him and the Fool people will scatter forever.

Woe. It’s never the case that I’ve found the king of fools because — sometimes only minutes later — I stumble across a still greater fool, and I wonder if I’m the King of Fools for believing that I’ll ever find His Fooliness.

You see, friend, if you cannot see the redeeming value of 4chan, I weep for you. It must be difficult to live without eyes. If you think you are Mr-oh-so-sophisticated, I ask you: where do you think memes come from? Yes, friend. Memes come from 4chan. All of them.

But it’s more than memes. 4chan is a place where people can say whatever they please, or at least the closest to such a place I’ve yet to find on the internet. There is no one pretending to be offended in order to score points on the I’m-the-most-offended game.¹ On 4chan, if you are a racist, a woman-hater, a man-hater, a fascist, a communist, a Jew or an anti-semite, you can be you. There is no Cathedral,² no social-hate-machine poised to vilify you for speaking your mind. On 4chan, if you wish to spew hate, spew hate, and if you wish to spew love, spew love.

Forced anonymity is an amazing medium. People can be real with you in a way that they can’t in any other venue. I have shared and received support from anons on different 4chan boards — people with no reason to give a fuck about me, people I will never knowingly interact with again. This, more than anything, ought to be evidence of some capacity for human decency.

1. There is another game people like to play. It’s called I’m-a-good-person-sleight-of-hand. Whoever has the most virtue points wins the game. To score virtue points, you need to convince other people that you’re a good, moral being without lifting a finger to improve the world. I have written about this before here.

2. A term coined by Mencius Moldbug, representing the self-organizing consensus of society as a whole — through the media and other institutions. Specifically, that part of society which condemns opposing ideologies as evil.

There was a post about a week ago about how new computer science students don’t get the Unix philosophy and the power (and great responsibility) of the command line. I don’t know these people. Most of my dev time is between Emacs, a terminal, and a web browser.

But during this discussion, or maybe in the article itself, there was an argument along the lines of: kids don’t need to learn how to use find or locate when they have Spotlight, and I nodded along, swallowing this like so much bad medicine.

Until, just moments ago, I went to open up Google Chrome and was like, hey, I’ll just use Spotlight to do it. So I tried. And I waited, and then waited a bit more, and remembered: oh, right, Spotlight is a piece of shit that never actually manages to find anything. Need to search for something? Oh, too bad, out of commission, I’m busy indexing your entire machine for the one hundredth time today and, surprise, this breaks the entire utility.

(Googling around seems to reveal this as an OS X bug fixed in a more recent update. No doubt that introduces more bugs and the Sisyphean cycle continues.)