The challenge in learning something is never in understanding its content or in retaining the knowledge over time. The challenge and only benefit to learning is being able to apply what you have learned when the time is right. Call this “prescience.”
When you learn something new, you will tend to give it a high priority. In fact, in that moment, it could emerge as the most important thing in your life. But soon enough, other things will take over attention, and suddenly the new piece of information has joined the old bundle of discarded information accumulated over the years.
The recency effect explains this point well. We tend to make decisions and judgements, not based on an objective analysis of available data, but on the most recent information we have been given.
How to maintain prescience? The only thing you can do to resolve this problem is to organize the information you take in. You can set up a 3 star system. One star if it’s important to you at the moment. Two stars if you are positive that it is important in the future. And 3 stats if you are positive it is important in the future, a day from now.
The reason why the third star depends on a 24 hour lag is because it’s not too far into the future that you lose sight of why the info is pertinent. And it’s not too short that you are not merely overreacting at the moment.
The final step is the ultimate challenge but this is where the wheat is separated from the chaff… Each month, relegate all one star and two starred information into an archive. And keep the 3 star pieces of information (tasks, piece of knowledge) in your main list.