Protégé Effect

Want to learn something twice as fast? Teach it. The student preparing to explain a topic studies differently — deeper, more organized, hunting for gaps — because teaching exposes what mere study hides: whether you actually understand.

The mechanism is accountability to clarity. Reading lets you nod past fog; teaching makes fog impossible — the student's face is a mirror that shows instantly whether the idea survived the journey. To explain, you must first reorganize the knowledge into something that can travel, and that reorganization is the learning.

This is why the best students are often found tutoring the weakest, why new doctors learn most in their first year of supervising, why the workshop's master understands the craft in a way the skilled journeyman does not.

So build teaching into your learning, whatever your level. Explain the new idea to the empty room, to the patient friend, to the notebook. If the explanation wobbles, the understanding was imaginary. You do not fully know a thing until you have handed it to someone else intact.