Zettels

Zettels is command line tool which implements Niklas Luhmann's system of a "Zettelkasten". It uses libzettels as a backend.

If you have no idea what a Zettelkasten is, read below at "What the heck is a Zettelkasten?"

Zettels is still in alpha stage and probably buggy.

What does Zettels do?

Zettels is a tool to index markdown files (your zettels). It takes a directory (your Zettelkasten's root directory) containing Markdown files (which may be in sub-directories) with a YAML metadata block (as defined by pandoc).

Zettels bundles the information about the relations between these files (your zettels) in a queryable index. To populate this index, Zettels does two things: 1. It inspects the fields title, keywords and followups of the YAML metadata block.

```{.yaml}

title: 'Example Zettel' keywords: [example, question] followups: [file.md, subdir/anotherfile.md, ../yetanotherfile.md] foo: 'Potentially more data ignored by libzettels.' ... `` 2. It parses the inline-style links (likeexample`) of the markdown document body and extracts the targets of these links.

The resulting index contains the metadata and the targets of the hyperlinks.

Have a look at the files in examples/Zettelkasten and examples/index.yaml to get a better idea.

It's intended to be used for a "Zettelkasten" like Niklas Luhmann used it.

What the heck is a Zettelkasten?

"Zettel" is German for "note" or "slip of paper". "Kasten" is German for "box". Think of old style library catalogues.

Obviously, this piece of software is not a box of paper sheets. However, Niklas Luhmann used such a box in a very specific way for his academic work.

A wonderful introduction in Luhmann's system of a Zettelkasten are the slides of a talk by Daniel Lüdecke: Introduction to Luhmann's Zettelkasten-Thinking

In Luhmann's own words: Communicating with Slip Boxes (translation of "Kommunikation mit Zettelkästen").

If you speak German, there's more:

• Luhmann, Niklas (1981): Kommunikation mit Zettelkästen. Ein Erfahrungsbericht. in: H. Baier / H.M. Kepplinger / K. Reumann (Eds.), Öffentliche Meinung und sozialer Wandel. Opladen: Westdeutscher Verlag. pp. 22-28
• Daniel Lüdecke: Luhmanns Arbeitsweise im elektronischen Zettelkasten
• Thomas Schlesinger: Wissen konservieren und kuratieren mit dem Zettelkasten nach Niklas Luhmann
• Universität Bielefeld: Video - Einblicke in das System der Zettel - Geheimnis um Niklas Luhmanns Zettelkasten

Alternatives

If you're looking for a GUI, all-in-one approach to implementing Luhmann's idea into software, I can recommend Daniel Lüdecke's Zettelkasten (sjPlot/Zettelkasten).

Zettel format

Zettels doesn't require your markdown files to have a metadata block. But to be really effective parts of your Zettelkasten, a YAML metadata block containing an entry for title, keywords and followups is necessary.

```{.yaml}

title: 'Example Zettel' keywords: [example, question] followups: [file.md, subdir/anotherfile.md, ../yetanotherfile.md] ... ```

If no such metadata is present, Zettels will replace it with appropriate "empty" values in the index:

• title: "untitled"
• keywords: "[]"
• followups: "[]"

Instead of finishing the metadata block with ... you can also use ---.

```{.yaml}

title: 'Example Zettel' keywords: [example, question]

followups: [file.md, subdir/anotherfile.md, ../yetanotherfile.md]

```

In fact, a zettel file may contain several YAML-blocks. However, Zettels will only parse the first one. The metadata block may contain a variety of other entries (e.g. author, date) – maybe for other tools, like pandoc – but those other entries are ignored by Zettels and do not become part of Zettels' index.

To manually link between zettels, use the "inline syntax" for markdown hyperlinks: [.markdown] [link text](url)

Links between zettel files should be relative links. The same is true for entries in followups.

Usage

tl;dr

1. run zettels setup for config
2. run zettels -h to see usage info

Search and inspect

There are two main ways of querying the Zettelkasten.

1. Search

Searching is a means to find an entry into the Zettelkasten. Zettels implements searching the title and keywords fields of the zettel. Just for the sake of completeness: searching the contents of the zettel is not a functionality of zettels. For that there are specialized tools like grep oder ripgrep out there.

Search for keywords -k, --keywords: zettels -k foo

Search for title -t, --title or -e, --exacttitle: zettels -t foo

Both can be combined: zettels -k foo -t bar

Results can be limited to zettels that match all queries: -a, --all zettels -k foo -t bar -a

And of course, that applies to mor than one search term, too. zettels -k foo bar -a

2. Inspect

Inspecting the relations between zettels is the second way of querying the zettelkasten. Inspection requires a "scope", meaning a list of zettels to inspect. This scope is either specified by the user, or it's the result of search or it's the whole zettelkasten.

For inspecting the "followup" relation, a key concept are "sequences". When a zettel designates another as a followup, they form a sequence. Further followups extend that sequence or might branch into subsequences.

Show to which sequences zettels specified by SCOPE belong -s, --sequences: zettels -s file1.md

Show all zettels of the sequences specified by SCOPE -z, --zettels: zettels -z file1.md

Show zettels that belong to the sequence(s) specified by SCOPE, plus all ancestors of SCOPE -f, --family: zettels -f file1.md

Show zettels that belong to the sequence(s) specified by SCOPE, plus all ancestors of SCOPE, plus all descendants of those ancestors -w, --wholefamily: zettels -w file1.md

For inspecting the "link" relation, we can inspect SCOPE's outgoing links -l, --links: zettels -l file1.md

or incoming links -i, --incoming: zettels -i file1.md

Both

As mentioned before, the result of a search can be used as SCOPE for inspection. So this will show all outgoing links of zettels that have the word "foo" in their titles: zettels -t foo -l