A good description from Bob Doto.

As humans we're good at separating things based on categories. The Dewey Decimal System systematically separates mathematics and history into disparate locations, but your zettelkasten shouldn't force this by overthinking categories. Perhaps the overlap of math and history is exactly the interdisciplinary topic you're working toward? If this is the case, just put cards into the slip box closest to their nearest related intellectual neighbor—and by this I mean nearest related to you, not to Melvil Dewey or anyone else. Over time, through growth and branching, ideas will fill in the interstitial spaces and neighboring ideas will slowly percolate and intermix. Your interests will slowly emerge into various bunches of cards in your box. Things you may have thought were important can separate away and end up on sparse branches while other areas flourish.

If you make the (false) choice to separate math and history into different "sections" it will be much harder for them to grow and intertwine in an organic and truly disciplinary way. Universities have done this sort of separation for hundreds of years and as a result, their engineering faculty can be buildings or even entire campuses away from their medical faculty who now want to work together in new interdisciplinary ways. This creates a physical barrier to more efficient and productive innovation and creativity. It's your zettelkasten, so put those ideas right next to each other from the start so they can do the work of serendipity and surprise for you. Do not artificially separate your favorite ideas. Let them mix and mingle and see what comes out of them.

If you feel the need to categorize and separate them in such a surgical fashion, then let your index be the place where this happens. This is what indices are for! Put the locations into the index to create the semantic separation. Math related material gets indexed under "M" and history under "H". Now those ideas can be mixed up in your box, but they're still findable. DO NOT USE OR CONSIDER YOUR NUMBERS AS TOPICAL HEADINGS!!! Don't make the fatal mistake of thinking this. The numbers are just that, numbers. They are there solely for you to be able to easily find the geographic location of individual cards quickly or perhaps recreate an order if you remove and mix a bunch for fun or (heaven forfend) accidentally tip your box out onto the floor. Each part has of the system has its job: the numbers allow you to find things where you expect them to be and the index does the work of tracking and separating topics if you need that.

The broader zettelkasten, tools for thought, and creativity community does a terrible job of explaining the "why" portion of what is going on here with respect to Luhmann's set up. Your zettelkasten is a crucible of ideas placed in juxtaposition with each other. Traversing through them and allowing them to collide in interesting and random ways is part of what will create a pre-programmed serendipity, surprise, and combinatorial creativity for your ideas. They help you to become more fruitful, inventive, and creative.

Broadly the same thing is happening with respect to the structure of commonplace books. There one needs to do more work of randomly reading through and revisiting portions to cause the work or serendipity and admixture, but the end results are roughly the same. With the zettelkasten, it's a bit easier for your favorite ideas to accumulate into one place (or neighborhood) for easier growth because you can move them around and juxtapose them as you add them rather than traversing from page 57 in one notebook to page 532 in another.

If you use your numbers as topical or category headings you'll artificially create dreadful neighborhoods for your ideas to live in. You want a diversity of ideas mixing together to create new ideas. To get a sense of this visually, play the game Parable of the Polygons in which one categorizes and separates (or doesn't) triangles and squares. The game created by Vi Hart and Nicky Case based on the research of Thomas Schelling provides a solid example of the sort of statistical mechanics going on with ideas in your zettelkasten when they're categorized rigidly. If you rigidly categorize ideas and separate them, you'll drastically minimize the chance of creating the sort of useful serendipity of intermixed and innovative ideas.

It's much harder to know what happens when you mix anthropology with complexity theory if they're in separate parts of your mental library, but if those are the things that get you going, then definitely put them right next to each other in your slip box. See what happens. If they're interesting and useful, they've got explicit numerical locators and are cross referenced in your index, so they're unlikely to get lost. Be experimental occasionally. Don't put that card on Henry David Thoreau in the section on writers, nature, or Concord, Massachusetts if those aren't interesting to you. Besides everyone has already done that. Instead put him next to your work on innovation and pencils because it's much easier to become a writer, philosopher, and intellectual when your family's successful pencil manufacturing business can pay for you to attend Harvard and your house is always full of writing instruments from a young age. Now you've got something interesting and creative. (And if you must, you can always link the card numerically to the other transcendentalists across the way.)

In case they didn't hear it in the back, I'll shout it again: ACTIVELY WORK AGAINST YOUR NATURAL URGE TO USE YOUR ZETTELKASTEN NUMBERS AS TOPICAL HEADINGS!!!

If you don't refer back to your notes for any reason, why bother taking them? Were they so boring? Was there nothing of surprise in them for having taken them in the first place?

Often note taking (writing) for understanding can be initially useful, but reviewing over these can be less useful in a larger corpus of notes. File the boring and un-useful things away. Center the important and the surprising.

Example of Brian Eno using ITunes as a digital music zettelkasten. He's got 2,800 pieces of unreleased music which he plays on random shuffle for serendipity, memory, and potential creativity. The experience seems to be a musical one which parallels Luhmann's ideas of serendipity and discovery with the ghost in the machine or the conversation partner he describes in his zettelkasten practice.

Journalists emphasize novelty because it underlines newsworthiness.

Alternately, researchers underline novelty, particularly in papers, because it underlines technology that might be sold/transferred and thus patented, a legal space that specifically looks at novelty as a criterion. By saying something is novel in the research paper, it's more likely that a patent examiner will be primed to believe it.

Oppenheimer doesn't keep track of specific cards (he didn't discuss how he files them, other than loosely together, potentially for specific projects) and finds that this creates a greater amount of surprise for him when searching for ideas within his system.

Missing here is any sort of topic or subject headings.... double check this as it's a key to most systems.

"hot nodes"? I've not come across this as a thing... source?

I'll push back on this a bit. I suspect that even though one might create multiple links to digital notes in all directions like this, it really doesn't happen happen at scale like this in practice.

I'd be willing to guess that very few people in the digital space are linking their ideas to more than two or three others. In fact, I suspect that if you looked at many digital ZKs you'd find a lot of orphaned notes floating around.

Separately, even in the analog space, the two links (down or forward) isn't always correct either. I cross link all over the place. The one constant benefit of the analog is that you're generally required to create at least one link because you have to place the card somewhere, and this isn't the case in most digital contexts/tools.

I'd posit that it's a lot of work to link a new idea into your system once much less in multiple places. Generally the more ideas you can link/cross-link it to, the more likely you'll run across it in the future and have potential to reuse it. I'd also suggest that the more links it's got, the better you'll "own" it. These addition links will also allow you to better compare/contrast various ideas by juxtaposing them in the future.

Theorem: more (good/great) links = more complexity which yields more "life", serendipity, and surprise to be found in your slip box for future use.

The area of serendipity becomes much more powerful when one has ideas both directly interlinked, ideas categorized with subject headings or tags, or when one can have affordances like auto-complete.

The method Forte suggests and outlines allows for some serendipity, but not as much as other methods with additional refinements. Serendipity in Forte's method isn't as strong as in others.

In this section he's talking about some of the true "magic of note taking" which is discussed by Luhmann and others.

link to:<br /> Luhmann's writings on serendipity and surprise when using his zettelkasten (Communication with the Slipbox...)<br /> Ahrens mentions of this effect

The most valuable work one can do in note taking is creating active links from one piece of knowledge to another, particularly if they're both surprising.

Anecdotally I do see a lot of people putting all of their work into collecting notes, and none of it rephrasing things into their own words to improve understanding or linking ideas together to create new ideas. The latter are both far superior to the former.

Your notes shouldn't be a place to collect what you already know.

What a god-awful reference for Claude Shannon. Obviously he found it in his reading through serendipity and didn't bother chasing down the original quote for publication...

Four broad criteria for collecting notes: - Is it surprising? - Is it useful? - Is it personal? - Does it inspire me?

Forte places these in the exact reverse order, but I would prefer to place them in order of importance to me, based on experience. I don't use the inspiration portion as often, but it may be more valuable for fiction writers, artists, and other creatives.

Coming to a text with too rigid a set of questions or preconceived categories may cause you to be blinded by what you expect to get out of it rather than allowing the text to surprise you with new and interesting insights you may not have anticipated.

If the best ideas are the ones we haven't anticipated, how are we defining "best"? Most surprising from an information theoretic perspective? One which creates new frontiers of change? One which subsumes or abstracts prior ideas within it? Others?

In a valuable article, Lorraine Daston, ‘Perché i fatti sono brevi?’, Quaderni storici 108 (2001), 745–70, esp. 756–59, noted that a clear analogy exists between these features and the art of excerpting.

Can one trick oneself into forced context collapse with relation to the material one is reading in such a way so as to force surprise and the creation of new ideas by then re-contextualizing them into one's system of notes?

I'm not completely sure I can agree with this. Perhaps I'm missing part of his point?

There is a quirky relationship here to the idea of a personbyte, the complete amount of information and knowledge a person can have. Even misty memories that a person can remember or be reminded of are part of this knowledge. Perfect recall isn't necessary as some things can potentially be reconstituted with some thought towards recreation of an idea.

Compare this with the idea of epic poetry and song of the Yugoslavian guslars. Some may be more artful than others, but at what point are they telling a new story?

The key question Alberto Cevolini is exploring here.

This is what I have been arguing all along as I've been doing my research as well.

Breen, Liz, and Sarah Schiffling. ‘The UK’s Speedy COVID-19 Vaccine Rollout: Surprise Success or Planned Perfection?’ The Conversation. Accessed 15 November 2021. http://theconversation.com/the-uks-speedy-covid-19-vaccine-rollout-surprise-success-or-planned-perfection-155922.

This is a basic tenet of information theory. Interesting to see it appear in a work on writing.

Harp, N., Dodd, M. D., & Neta, M. (2020). Emotional working memory load selectively increases negativity bias [Preprint]. PsyArXiv. https://doi.org/10.31234/osf.io/jnesc

Moore, D. A., & Schatz, D. (2020). Overprecision increases subsequent surprise [Preprint]. PsyArXiv. https://doi.org/10.31234/osf.io/wfcbv

The 1860s.

The farmer's wife is a "working partner" not his employee. That seems like an audacious statement for the time. Was it?

I found this surprising. I would think using titles like Doctor and Professor would have been considered just as objectionable as Mr., Mrs., and Miss.

The Bottle has agency. That's curious.

another instance that surprises us since we thought Thanksgiving was a lasting national tradition since the first feast in 1692.

It is always a pleasure to be surprised by something we are reading, and I am glad you are noting your reaction to a reading here.

Il y a deux semaines, c’était l’anniversaire de mon meilleur ami. Elle étudie à Davidson. Deux semaines avant son anniversaire, elle m’a demandé de visiter pour son anniversaire, mais j’ai dit que je ne pouvais pas. Pendant les deux semaines, j’ai parlé avec mon autre ami à Davidson et je lui ai surprise. Elle était très heureuse et surprise! Mon ami et moi, nous avons planifié la surprise très bien. C’était un très bon weekend.

This number seems staggeringly low compared to my experience with friends. Really? I may look this stat up or find out where it comes from.

Aziz is doing research?! I'm visualizing him doing a focus group interview

This surprises me. Sounds like Aziz is skeptical of "natural" love. Will he be making an argument for algorithmic match-making?