In 1983, at the dawn of the personal computer age, Apple Inc. in promotional film entitled "Lisa Soul Of A New Machine" touted their new computer, a 16-bit dual disk drive "personal office system", as something that would do away with "the cluttered desk, index cards, file folders, the in-out basket, [and] the calculator." (00:01)

Some of these things moved to the realm of the computer including the messy desk(top) now giving people two messy desks, a real one and a virtual one. The database-like structure of the card index also moved over, but the subjective index and its search power were substituted for a lower level concordance search.

30 years on, for most people, the value of the database idea behind the humble "index card" has long since disappeared and so it seems here as if it's "just" another piece of cluttery paper.

Appreciate the rosy framing of the juxtaposition of "past" and "future" jumping over the idea of the here and now which includes the thing they're selling, the Lisa computer. They're selling the idealized and unclear future even though it's really just today.

Julius Kaiser contemporaneously posits that mass manufacture and maximizing efficiency (greater output for minimum input) are the primary drivers of card index system use in the early 20th century. These also improve both precision and accuracy in handling information which allow for better company or factory operation, which would have been rising concerns for businesses and manufacturing operations at the rise of scientific management during the time period.

The data of the past is congruent with the current psychological trends that face the education system of today. Developmentalists have charted how children construct and revise intuitive theories. In turn, a variety of theories have developed because of the greater use of statistical information that supports probabilistic contingencies that help to better inform us of causal models and their distinctive cognitive functions. These studies investigate the physical, psychological, and social domains. In the case of intuitive psychology, or "theory of mind," developmentalism has traced a progression from an early understanding of emotion and action to an understanding of intentions and simple aspects of perception, to an understanding of knowledge vs. ignorance, and finally to a representational and then an interpretive theory of mind.

The mechanisms by which life evolved—from chemical beginnings to cognizing human beings—are central to understanding the psychological basis of learning. We are the product of an evolutionary process and it is the mechanisms inherent in this process that offer the most probable explanations to how we think and learn.

Bada, & Olusegun, S. (2015). Constructivism Learning Theory : A Paradigm for Teaching and Learning.

optimization-procrastination trap is related to shiny object syndrome - the idea of tweaking one's system constantly

perfect tool trap - guess what? there isn't one

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.

The Outline of Knowledge appears in the Propædia volume of the Encyclopedia Britannica. It is similar to various olther classification systems like the Dewey Decimal system or the Universal Decimal Classification.

Sloman, S. A. (2021). How Do We Believe? Topics in Cognitive Science, 0(2021), 1–14. https://doi.org/10.1111/tops.12580

Evans, M. C., & Cvitanovic, C. (2018). An introduction to achieving policy impact for early career researchers. Palgrave Communications, 4(1), 1–12. https://doi.org/10.1057/s41599-018-0144-2

Hahn, U., Lagnado, D., Lewandowsky, S., & Chater, N. (2020). Crisis knowledge management: Reconfiguring the behavioural science community for rapid responding in the Covid-19 crisis [Preprint]. PsyArXiv. https://doi.org/10.31234/osf.io/hsxdk