This is my rephrasing of (Ahrens, 2017, How to Take Smart Notes). I added some personal comments.

The amazing note-taking method of Luhmann

To be more productive, it's necessary to have a good system and workflow. The Getting Things Done system (collect everything that needs to be taken care of in one place and process it in a standardised way) doesn't work well for academic thinking and writing, because GTD requires clearly defined objectives, whereas in doing science and creative work, the objective is unclear until you've actually got there. It'd be pretty hard to "innovate on demand". Something that can be done on demand, in a predetermined schedule, must be uncreative.

Enter Niklas Luhmann. He was an insanely productive sociologist who did his work using the method of "slip-box" (in German, "Zettelkasten").

Making a slip-box is very simple, with many benefits. The slip-box will become a research partner who could "converse" with you, surprise you, lead you down surprising lines of thoughts. It would nudge you to (number in parenthesis denote the section in the book that talks about the item):

Find dissenting views (10.2, 12.3)
Really understand what you learned (10.4, 11.2, 11.3, 12.6)
Think across contexts (12.5)
Remember what you learned (11.3, 12.4)
Be creative (12.5, 12.6, 12.7, 13.2)
Get the gist, not stuck on details (12.6)
Be motivated (13.3)
Implement short feedback loops, which allows rapid improvements (12.6, 13.5)

Four kinds of notes

Fleeting notes

These are purely for remembering your thoughts. They can be: fleeting ideas, notes you would have written in the margin of a book, quotes you would have underlined in a book.

They have no value except as stepping stones towards making literature and permanent notes. They should be thrown away as soon as their contents have been transferred to literature/permanent notes (if worthy) or not (if unworthy).

Examples:

Jellyfish might be ethically vegan, since they have such a simple neural system, they probably can't feel pain.

Ch. 9 How to ~~attention~~ attend:

One thing at a time. No multitasking

When writing, attend to idea flow. Meaning, not wording. ...

Literature notes

These summarize the content of some text, and give the citation.

Example:

(Kahneman & Tversky, 1973) shows that people often do not take into account the prior when doing a Bayesian probability problem. In particular, when no evi

...

Abdur-Rahmaan Janhangeer

Abdur-Rahmaan Janhangeer