Lesson 1

Storage strength beats fluency

Why the lessons in this repo are deliberately a little bit hard.

Recognising an answer feels like knowing it. Fluency strength is in-the-moment retrieval; storage strength is whether you still have it next month. Only the second one is the goal.¹

The three levers

All three feel worse and work better. That inversion is the whole idea:

Conditions of learning that make performance improve rapidly often fail to support long-term retention.Bjork & Bjork, Making Things Hard on Yourself, But in a Good Way

In code

// spacing, roughly
const next = (n) => Math.round(2.5 ** n);   // 1, 6, 16, 39 days