imposed system or on one’s own non-generalizable system, at least when it comes to the subdivisions.

Heyde makes the suggestion of using one's own classification system yet again and even advises against "having to rely on a stranger's imposed system". Does Luhmann see this advice and follow its general form, but adopting a numbering system ostensibly similar, but potentially more familiar to him from public administration?

In a break from the more traditional subject heading filing system of many commonplacing and zettelkasten methods, in addition to this sort of scheme Heyde also suggests potentially using the Dewey Decimal System for organizing one's knowledge.

While Luhmann doesn't use Dewey's system, he does follow the broader advice which allows creating a dense numbering system though he does use a different numbering scheme.

While Heyde spends a significant amount of time on encouraging one to index and file their ideas under one or more subject headings, he address the objection:

“Doesn’t this neglect the importance of sequentiality, context and development, i.e. doesn’t this completely make away with the well-thought out unity of thoughts that the original author created, when ideas are put on individual sheets, particularly when creating excerpts of longer scientific works?"

He suggests that one file such ideas under the same heading and then numbers them sequentially to keep the original author's intention. This might be useful advice for a classroom setting, but perhaps isn't as useful in other contexts.

But for Luhmann's use case for writing and academic research, this advice may actually be counter productive. While one might occasionally care about another author's train of thought, one is generally focusing on generating their own train of thought. So why not take this advice to advance their own work instead of simply repeating the ideas of another? Take the ideas of others along with your own and chain them together using sequential numbers for your own purposes (publishing)!!

So while taking Heyde's advice and expand upon it for his own uses and purposes, Luhmann is encouraged to chain ideas together and number them. Again he does this numbering in a way such that new ideas can be interspersed as necessary.

Heydes Overbearing System

Heyde's method spends almost a full page talking about what to do if one extends a note or writes longer notes. He talks about using larger sheets of paper, carbon copies, folding, dating, clipping, and even stapling.

His method seems to skip the idea of extending a particular card of potentially 2 or more "twins"/"triplets"/"quadruplets" which might then also need to be extended too. Luhmann probably had a logical problem with this as tracking down all the originals and extending them would be incredibly problematic. As a result, he instead opted to put each card behind it's closest similar idea (and number it thus).

If anything, Heyde's described method is one of the most complete of it's day (compare with Bernheim, Langlois/Seignobos, Webb, Sertillanges, et al.) He discusses a variety of pros and cons, hints and tips, but he also goes deeper into some of the potential flaws and pitfalls for the practicing academic. As a result, many of the flaws he discusses and their potential work arounds (making multiple carbon copies, extending notes, etc.) add to the bulk of the description of the system and make it seem almost painful and overbearing for the affordances it allows. As a result, those reading it with a small amount of knowledge of similar traditions may have felt that there might be a better or easier system. I suspect that Niklas Luhmann was probably one of these.

It's also likely that due to these potentially increasing complexities in such note taking systems that they became to large and unwieldly for people to see the benefit in using. Combined with the emergence of the computer from this same time forward, it's likely that this time period was the beginning of the end for such analog systems and experimenting with them.

Heyde specifically highlights that planning for one's future search efforts by choosing the right keyword or even multiple keywords "seems to be the biggest complaint about the entire system of the slip box and its merit."

Niklas Luhmann apparently spent some time thinking about this, or perhaps even practicing it, before changing his system so that the issue was no longer a problem. As a result, Luhmann's system is much simpler to use and maintain.

Given his primary use of his slip box for academic research and writing, perhaps his solution was in part motivated by putting the notes and ideas exactly where he would both be able to easily find them, but also exactly where he would need them for creating final products in journal articles and books.

Heyde indicates how "valuable notes and chains of thought are" but also points out "how uncontrollable and irretrievable" they are.

This statement is strong evidence along with others in this chapter which may have inspired Niklas Luhmann to invent his iteration of the zettelkasten method of excerpting and making notes.

(link to: Clemens /Heyde and Luhmann timeline: https://hypothes.is/a/4wxHdDqeEe2OKGMHXDKezA)

Presumably he may have either heard or seen others talking about or using these general methods either during his undergraduate or law school experiences. Even with some scant experience, this line may have struck him significantly as an organization barrier of earlier methods.

Why have notes strewn about in a box or notebook as Heyde says? Why spend the time indexing everything and then needing to search for it later? Why not take the time to actively place new ideas into one's box as close as possibly to ideas they directly relate to?

But how do we manage this in a findable way? Since we can't index ideas based on tabs in a notebook or even notebook page numbers, we need to have some sort of handle on where ideas are in slips within our box. The development of European card catalog systems had started in the late 1700s, and further refinements of Melvil Dewey as well as standardization had come about by the early to mid 1900s. One could have used the Dewey Decimal System to index their notes using smaller decimals to infinitely intersperse cards on a growing basis.

But Niklas Luhmann had gone to law school and spent time in civil administration. He would have been aware of aktenzeichen file numbers used in German law/court settings and public administration. He seems to have used a simplified version of this sort of filing system as the base of his numbering system. And why not? He would have likely been intimately familiar with its use and application, so why not adopt it or a simplified version of it for his use? Because it's extensible in a a branching tree fashion, one can add an infinite number of cards or files into the midst of a preexisting collection. And isn't this just the function aktenzeichen file numbers served within the German court system? Incidentally these file numbers began use around 1932, but were likely heavily influenced by the Austrian conscription numbers and house numbers of the late 1770s which also influenced library card cataloging numbers, so the whole system comes right back around. (Ref Krajewski here).

(Cross reference/ see: https://hypothes.is/a/CqGhGvchEey6heekrEJ9WA

Other pieces he may have been attempting to get around include the excessive work of additional copying involved in this piece as well as a lot of the additional work of indexing.

One will note that Luhmann's index was much more sparse than without his methods. Often in books, a reader will find a reference or two in an index and then go right to the spot they need and read around it. Luhmann did exactly this in his sequence of cards. An index entry or two would send him to the general local and sifting through a handful of cards would place him in the correct vicinity. This results in a slight increase in time for some searches, but it pays off in massive savings of time of not needing to cross index everything onto cards as one goes, and it also dramatically increases the probability that one will serendipitously review over related cards and potentially generate new insights and links for new ideas going into one's slip box.

What edition of this book did Luhmann have/use?

His edition will establish a potential lower threshold for the point in his life at which he used it (ie college, law school, other).

What differences are there between the edition I've read portions of and this 10th edition exist? Did Luhmann's edition have this same outline/contents page in this form? Does my analysis still stand if this changes?

While Heyde outlines using keywords/subject headings and dates on the bottom of cards with multiple copies using carbon paper, we're left with the question of where Luhmann pulled his particular non-topical ordering as well as his numbering scheme.

While it's highly likely that Luhmann would have been familiar with the German practice of Aktenzeichen ("file numbers") and may have gotten some interesting ideas about organization from the closing sections of the "Die Kartei" section 1.2 of the book, which discusses library organization and the Dewey Decimal system, we're still left with the bigger question of organization.

It's obvious that Luhmann didn't follow the heavy use of subject headings nor the advice about multiple copies of cards in various portions of an alphabetical index.

While the Dewey Decimal System set up described is indicative of some of the numbering practices, it doesn't get us the entirety of his numbering system and practice.

One need only take a look at the Inhalt (table of contents) of Heyde's book! The outline portion of the contents displays a very traditional branching tree structure of ideas. Further, the outline is very specifically and similarly numbered to that of Luhmann's zettelkasten. This structure and numbering system is highly suggestive of branching ideas where each branch builds on the ideas immediately above it or on the ideas at the next section above that level.

Just as one can add an infinite number of books into the Dewey Decimal system in a way that similar ideas are relatively close together to provide serendipity for both search and idea development, one can continue adding ideas to this branching structure so they're near their colleagues.

Thus it's highly possible that the confluence of descriptions with the book and the outline of the table of contents itself suggested a better method of note keeping to Luhmann. Doing this solves the issue of needing to create multiple copies of note cards as well as trying to find cards in various places throughout the overall collection, not to mention slimming down the collection immensely. Searching for and finding a place to put new cards ensures not only that one places one's ideas into a growing logical structure, but it also ensures that one doesn't duplicate information that may already exist within one's over-arching outline. From an indexing perspective, it also solves the problem of cross referencing information along the axes of the source author, source title, and a large variety of potential subject headings.

And of course if we add even a soupcon of domain expertise in systems theory to the mix...

While thinking about Aktenzeichen, keep in mind that it was used in German public administration since at least 1934, only a few years following Heyde's first edition, but would have been more heavily used by the late 1940's when Luhmann would have begun his law studies.

https://hypothes.is/a/CqGhGvchEey6heekrEJ9WA

When thinking about taking notes for creating output, one can follow one thought with another logically both within one's card index not only to write an actual paper, but the collection and development happens the same way one is filling in an invisible outline which builds itself over time.

Linking different ideas to other ideas separate from one chain of thought also provides the ability to create multiple of these invisible, but organically growing outlines.

Heyde, Johannes Erich, and Heinz Siegel. Technik des wissenschaftlichen Arbeitens (Inhalt). 10th ed. Berlin: Kiepert, 1970. oclc/1075391218

The table of contents of the 1970 10th Edition

A later edition of the text from which Niklas Luhmann ostensibly learned the methods behind his zettelkasten.