Learning is less about filling your head and more about changing what you notice.

Learning gets imagined as storage, with facts stacking up inside you. What actually changes is your perception, so you start seeing things in a scene that were always there and previously invisible. Learn about birds and a garden fills up; learn about engines and a noise becomes a diagnosis. The world is not more interesting afterwards; you are simply able to see more of what was already in front of you.

Look out for something you learned recently as you go about this week. Count how often it turns up now. That is a better test than any amount of recall.