Supermemo is a learning system that uses spaced repetition to seal knowledge in memory. I wrote about Supermemo and its inventor, Piotr Wozniak, for Wired. Since this piece is among the most requested I’m linking to the unformatted version that I have rights to here: Want to Remember Everything You’ll Ever Learn? Surrender To This Algorithm. (The Wired version contains some great photos and diagrams, so if you are you are a subscriber or are considering a subscription, you can look there for it.)

This story counts as one of my favorites, for three reasons. First, I owe to it my friendship with Wozniak. Although he does not travel and I have not yet been back to the northern coast of Poland where he lives, we remain in close contact, and I find that I’ve been deeply influenced by his unusual – some might say eccentric – point of view. He is an extreme rationalist, and a very happy and productive person. Second, I associate this story with the fact that, after a 40 years of  being monolingual, I learned Spanish using Supermemo. Although my Spanish contains many errors, it is serviceable enough for conversation on almost any topic with a sympathetic listener. After many other attempts, I finally made it up onto that first, hardest step in learning any language: getting enough loaded into memory to permit meaningful and wide-ranging communication. As for fluency, this will take a lifetime. But it is now a lot more fun. To stand at the edge of a nearly limitless language-culture is exciting. There are treasures everywhere.

The final reason the Wozniak story remains on my mind is that it left me with a difficult problem that I enjoy continuing to try to solve. Why isn’t this amazing technique more common? I explained some of the obvious reasons in my story. Still, I expected that, having launched the idea into an environment well suited to nourish it (many Wired readers are passionate learners, and many of them have software, design, and business skills), I would soon see some new implementations. And I was not disappointed. There are half a dozen versions of Supermemo in common use today. But they are used by very few people. Clearly, the problem remains unsolved.

I still think about this quite a lot. If you are a Supermemo user, I would like to hear from you.