How a flashcard app changed the way I think about my education

Today marks almost one year since I first started using Anki—a flashcard app with a twist. Anki minimizes the number of cards I have to review on any given day while maximizing how much I remember over the long term. And to my surprise, what started as a simple experiment has changed the way I approach my education.

Anki is a re-imagining of what flashcards should be like in the digital age. In order to understand how it works, you have to momentarily put aside your current conception of flashcards as 3x5 index cards that you might frantically create before a test and never use again.

Let’s start with a little cognitive science. Our brains tend to forget information gradually over time. If I don’t play a song on my guitar for a week, for instance, I’ll probably still remember it. But if I don’t play it for a year, I’ll probably have forgotten it. If I wanted to minimize the amount of time I have to practice, the trick would be to only play the song right when I’m about to forget it.

Anki is like a personal assistant that only shows me flashcards I’m about to forget. How does it do this? I add two-sided cards to Anki, and the app reveals a set number of new ones every day. At the bottom of each card are three buttons: again, good, and easy, each of which correspond to different time intervals.

Pressing a button is like saying, “Anki, send me this card again [x] days in the future.” The easier the card, the longer Anki waits to show it to me again. If the card is still easy after the specified number of days have elapsed, the app sends it even further into the future. And so on. Although I’ve accumulated 1,895 flashcards in Anki, I never have to review more than ten minutes a day because of the way they’re spaced out over time.


When I sit down to choose my courses for the semester, I’m often faced with a dilemma: why should I take a class if a) I can find all of its content on the web, and b) I’m going to forget a lot of what I learned a few months after the semester ends? Although students have been forgetting things since schools were first built, I think this is somewhat of a new problem. The fact that information is so readily accessible online makes the prospect of forgetting seem less important. This left me wondering if fact-heavy courses like Intro to the Human Brain or Macroeconomics were worth my time. It saddened me that I could sit in a classroom for a whole semester and come away with only vague memories of big ideas. Even still, I didn’t think it made sense to set aside time every day to review all of my notes from all of my classes after they were over.

Anki is a wonderful solution to this dilemma. After each class session, I take a few moments to translate my notes into Q&A-style Anki cards. I’m able to maintain all of that information at a cost of just ten minutes per day. Given the amount of money I’m spending on courses at Yale, this seems like a worthwhile investment. I’ve long believed learning doesn’t stop when a class ends, and this is an effective way of putting that philosophy into action.

There’s more than one kind of forgetting. The first is what cognitive scientist Eliezer Yudkowsky calls singlethink: you notice you are forgetting, and then you remember. The second, called doublethink, was coined by George Orwell: you forget, and then forget that you have forgotten. What I like about Anki is that it prevents doublethink—the far more dangerous kind of forgetting—and promotes singlethink. When you forget and forget that you’ve forgotten, you’re left with an unknown unknown. And it’s certainly hard to re-learn something that you don’t know you don’t know. With Anki at your side, you can never forget that you’ve forgotten a piece of information (as long as you’ve added it in the first place, of course).

In this way, Anki is effective even if you end up getting flashcards wrong. Why? Because it reminds you of what you don’t know. These known unknowns sow the seeds of curiosity. They provide new questions and areas for exploration. As memory champion Joshua Foer said:

Memory is like a spiderweb that catches information. The more it catches, the bigger it grows. And the bigger it grows, the more it catches. 

My friend Aaron Gertler once told me that one goal of education is to make your head a more interesting place to live. While it’s true that not every single fact I’ve ever learned in college will be relevant to my day-to-day life, they do make my head a more interesting place to live. Facts are like stepping stones in the river of thought. The more you know about the world, the more stepping stones in your river, and the easier it is to navigate. You can jump from one thing to the next with little effort and arrive somewhere completely unexpected. This is creativity. Anki gives me more strands in my web, more stones in my river. Here’s to another year with Anki.