reply to dandennison84 at https://forum.zettelkasten.de/discussion/comment/17921/#Comment_17921
I've written a bit before on The Two Definitions of Zettelkasten, the latter of which has been emerging since roughly 2013 in English language contexts. Some of it is similar to or extends @dandennison84's framing along with some additional history.
Because of the richness of prior annotation and note taking traditions, for those who might mean what we're jokingly calling ZK®, I typically refer to that practice specifically as a "Luhmann-esque zettelkasten", though it might be far more appropriate to name them a (Melvil) "Dewey Zettelkasten" because the underlying idea which makes Luhmann's specific zettelkasten unique is that he was numbering his ideas and filing them next to similar ideas. Luhmann was treating ideas on cards the way Dewey had treated and classified books about 76 years earlier. Luhmann fortunately didn't need to have a standardized set of numbers the way the Mundaneum had with the Universal Decimal Classification system, because his was personal/private and not shared.
To be clear, I'm presently unaware that Dewey had or kept any specific sort of note taking system, card-based or otherwise. I would suspect, given his context, that if we were to dig into that history, we would find something closer to a Locke-inspired indexed commonplace book, though he may have switched later in life as his Library Bureau came to greater prominence and dominance.
Some of the value of the Dewey-Luhmann note taking system stems from the same sorts of serendipity one discovers while flipping through ideas that one finds in searching for books on library shelves. You may find the specific book you were looking for, but you're also liable to find some interesting things to read on the shelves around that book or even on a shelf you pass on the way to find your book.
Perhaps naming it and referring to it as the Dewey-Luhmann note taking system or the Dewey-Luhmann Zettelkasten may help to better ground and/or demystify the specific practices? Co-crediting them for the root idea and an early actual practice, respectively, provides a better framing and understanding, especially for native English speakers who don't have the linguistic context for understanding Zettelkästen on its own. Such a moniker would help to better delineate the expected practices and shape of a note taking practice which could be differentiated from other very similar ones which provide somewhat different affordances.
Of course, as the history of naming scientific principles and mathematical theorems after people shows us, as soon as such a surname label might catch on, we'll assuredly discover someone earlier in the timeline who had mastered these principles long before (eg: the "Gessner Zettelkasten" anyone?) Caveat emptor.
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