Harrison defined his Ark of Studies as a machine.

reply to u/drogers8 at https://www.reddit.com/r/antinet/comments/14ot4na/inserting_a_maincards_with_lack_of_memory/

I would submit that your first sentence is wildly false.

What topic(s) cover your newly made cards? Look those up in your index and find where those potentially related cards are (whether you remember them or not). Go to that top level card listed in your index and see what's there or in the section of cards that come after it. Find the best card in that branch and file your new card(s) as appropriate. If necessary, cross-index them with sub-topics in your index to make them more findable in the future. If you don't find one or more of those topics in your index, then create a new branch and start an index entry for one or more of those terms. (You'll find yourself making lots of index entries to start, but it will eventually slow down—though it shouldn't stop—as your collection grows.)

Ideally, with regular use, you'll likely remember more and more, especially for active areas you're really interested in. However, take comfort that the system is designed to let you forget everything! This forgetting will actually help create future surprise as well as serendipity that will actually be beneficial for potentially generating new ideas as you use (and review) your notes.

And if you don't believe me, consider that Alberto Cevolini edited an entire book, broadly about these techniques—including an entire chapter on Luhmann—, which he aptly named Forgetting Machines!

I would argue that it is more subtle than this. It allows you to forget, but the aim is to allow you to learn, remember, and slowly build.

While the Syntopicon ultimately appears in book form, one must recall that it started life as a paper slip-based card index (Life v24, issue 4, 1948). This index can be queried in some of the ways one might have queried a library card catalog or more specifically the way in which Niklas Luhmann indicated that he queried his zettelkasten (Luhmann,1981). Unlike a library card catalog, The Syntopicon would not only provide a variety of entry places within the Western canon to begin their search for answers, but would provide specific page numbers and passages rather than references to entire books.

The Syntopicon invites the reader to make on the set whatever demands arise from his own problems and interests. It is constructed to enable the reader, no matter what the stages of his reading in other ways, to find that part of the Great Conversation in which any topic that interests him is being discussed. (p. 85)

While the search space for the Syntopicon wasn't as large as the corpus covered by larger search engines of the 21st century, the work that went into making it and the depth and focus of the sources make it a much more valuable search tool from a humanistic perspective. This work and value can also be seen in a personal zettelkasten. Some of the value appears in the form of having previously built a store of contextualized knowledge, particularly in cases where some ideas have been forgotten or not easily called to mind, which serves as a context ratchet upon which to continue exploring and building.

—u/spanchor

google translate:

The Zettelkasten always tends to know less than you do, but always as much as we have written on cards.

He says this, but his advice on how to use them is too scant and/or flawed. Where are they held? How are they indexed? How are they linked so that finding and using them in the future? (especially, other than rote memory or the need to have vague memory and the ability to search for them in the future?)

For Twyla Tharp, the most important feature of her project boxes is the fact that they free her from the worry of forgetting her ideas.

While placing our ideas into external memory devices like notebooks or zettelkasten may allow us to forget them, mnemotechniques allow us to perform a similar task, but provides us hooks upon which they might be hung by means of association with other ideas. These hooks and association can be reactivated at later times when the ideas may be needed.

The zettelkasten allows us to do multiple things. It encourages us to clarify our ideas by writing them down, we extend them by linking them to other contexts, we actively write towards a multitude of interesting goals, by writing, we can forget the original ideas which we can later serendipitously re-link to new concepts.

Note that this article is a revised and shortened form of a chapter in Cevolini's Forgetting Machines. I'm tempted to just read that instead...