3 minute read

One of the core themes that I find myself drawn to is learning and learning how to learn. This blog post is a weird mix of quotes and stories I found across several sources. If there is just one thing I want you to take away from this blog post it’s this:

💡 To learn, retrieve!

To learn, retrieve. That is the mantra I want you to remember. If you follow this mantra and gauge your actions against this mantra you will learn far more effectively than you would otherwise.

Testing effect and illusion of knowledge

Imagine two students. Student A, who studies 4 hours a day but only flips the book open, scans the content, and rereads the material. Student B, this student studies 4 hours a day but makes summaries of the chapters, flashcards of the content, and practises them regularly. Who do you think will know the material better?

Of course the answer is student B. It turns out that effortful retrieval of the material, for example with flashcards, sticks far better than simple reexposure to the material. This is called the testing effect.

One of the biggest dangers of learning is called the illusion of knowledge where you think you know something but you actually don’t. Simply rereading the material and being exposed to it again easily traps you like this. Have you ever been able to “follow” a difficult mathematics proof, but then on a test have been required to reproduce it only to be stuck on it? This is an illusion of knowledge, you thought you knew it (because you could follow it and were familiar with it) but you aren’t able to reproduce it.

Another benefit of testing is that students spend more time learning the material that they don’t know, because they tested it. They made some practice tests, identified gaps in their understanding, and can now study more effectively. This leads to doubly better learning because first the gaps are accurately identified and second the gaps are actually remedied with focused studying.

The way out of this is to not just follow the material, but to retrieve the material from memory. In other words: To learn, retrieve.

To learn, retrieve (test yourself studying practice tests and flashcards)

Drill until you can reflexively take the right action

A technique he had practised in his mind and in the operation room until it became the kind of reflexive manoeuvre you can depend on when the patient is spouting blood at 200 cubic centimetres per second.

To make sure that new learning is available exactly when you need it, you need to memorise the list of things that you need to worry about: step A, B, C, D, E, and then you drill them. Then there comes a time where you are in a tight situation and it is no longer thinking through the steps, it is now a matter of reflexively taking the right action.

Figure out what we want to learn, then drill that until we can retrieve it at a moment’s notice in high stress situations like surgery or a test. This means that you truly have internalised the knowledge: when you can produce it at the moment it really counts without really thinking about it.

To learn, retrieve (drill it until you can produce it when it matters)

Knowledge is like a beaded necklace

Knowledge is a bit like a beaded necklace. Imagine a child stringing cranberries on a thread and the child goes to hang it in the tree, only to find that they slip off on the other end. Without a knot there is no string, without a knot there is no necklace, no knowledge. Retrieval ties the knot for memory. Repeated retrieval snugs it up and adds a loop to make it fast.

To learn, retrieve (tie the beaded necklace).

Key takeaways

  • To learn, retrieve. Practising retrieval for new knowledge or a skill from memory is a potent tool for learning and durable retention. This is true for any task that the brain is asked to remember and call up again mentally in the future. This includes concepts, problem solving techniques, and motor skills.
  • Effortful (difficult) retrieval makes for stronger learning and retention. We think that learning is better when it is easier, but research shows the opposite. Learning sticks better when it is harder.
  • Repeated retrieval is even better. Repeated (spaced) retrieval does not only make memories more durable, but also increases your ability to retrieve knowledge the next time. Every time you recall you make it a bit easier to recall the same knowledge in the future.