[quarok]

Firstly, in terms of the distinction between learning and knowing -- the thing that matters most is the strength of the encoding in the brain. If you just memorise something with 0 understanding, the connections in the brain aren't as strong -- so they disappear. Whereas if you know something thoroughly, the connections are much, much stronger.

These strong connections are why when you go back and look at it, you recognise it and you know how to apply it - because you still have some of the residual memories from this strong encoding. But in the meantime, you probably haven't been able to apply it in an analogy for example.

Secondly - there's a classic on the topic of Spaced Repetition written by Gwern.[0] Gwern calculated that, given the average amount of time you spend testing yourself on something, and the exponential increase in how long you remember it, if you would spend more than 5 minutes per 10 years looking something up, you should use spaced repetition to remember it.

For transparency I work with OP on Save All.

0: https://www.gwern.net/Spaced-repetition

[mistermann]

> Firstly, in terms of the distinction between learning and knowing -- the thing that matters most is the strength of the encoding in the brain.

I'd vote for the ability to perform a skilful epistemic analysis of the retrieved information being more useful. I prefer this because it can overcome any natural immutable shortcomings in the underlying process.