I just cooked up this description of my system. it's a work in progress, not a formal commitment.
It distinguishes between two types of learning that are easily conflated and two relationships I might have to a subject:
| Already | Don't |
| Do | Do |
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Learn | | |
About | | |
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Learn | | |
To Do | | |
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Most subjects naturally fall into Learn-About/Don't-Do because there is no way of doing them...e.g. *The Pax Romana*, Hydrogen, Milly Vannilly.
Operating Harbor Freight Sawmills, Applying Category Theory, and Using Vim are also in Learn-about/Don't-do because I don't do them and even though I could learn to do them, I'm probably not going to start doing them any time soon (if ever).
Learn-About/Already-Do is not that different from Learn-To-Do/Already-Do. The main difference is the timeline. Learn-About is in the immediate or short-term future. Learn-To-Do tends to be long term and broad.
Like I said this is a rough sketch and YMMV.