244 - Unique Identifiers
UID Primary Purpose
The primary purpose of each unique identifier is the quite obvious. It serves as a way to point towards another piece of information. Whether it be point to a whole another note (e.g. see note Metacognition) or section of a note (e.g. see Metamemory section in Metacognition note). With a digital system you can create a clickable link to it (e.g. see 202006011558 Metacognition). The whole point of it is it allows you to pull up more information when needed.
The key here is that the UIDs is unique and you have some method of tracking titles that keep them unique. In Obsidian, it automatically scans your notes so you can’t create duplicate titles. Because time flows forward, generating a timestamp of that instant will also always create a unique identifier that won’t ever be duplicated.
A contrasting example of a identifier would be the #tags system within obsidian. A single tag can represent many different notes, so it is no long unique to the note. Unless you track your tags and make sure they are descriptive enough to be unique.
UID Secondary Purpose
All the different options also have a secondary purpose besides serving as a unique pointer to that note or section of information. Titles for example give you a quick idea of what the contents of the note will be. Time IDs will give you an idea when the note was created. Luhmann IDs allow you to pretty much infinitely expand on any section of information in a physical system. People also misunderstand them and use them to show hierarchical relations between notes (not judging it).
UID Option 1: Titles
Titles are the go to standard for note UIDs. They have the capability to be unique, give you a brief idea of the notes content, and make note retrieval easier. Typically we search for information through retrieval cues that take the form of words. So it makes sense to search for note titles in the form of words.
The problem with note titles is there is no easy way to organize them so they stay unique. You could have them all sorted by title alphabetically but then that will become a giant headache when your notes are heavily interlinked. You’ll be jumping all over the place to pull up a set of notes. That is why Luhmann IDs work so well. They can be forever expanded upon while also keeping notes relating to one topic near each other. All these problems go away with digital software , as the computer can easily search all your notes for a matching title. Because of clickable links and automatic searching, collecting a the relevant notes become easier.
UID Option 2: Time IDs
Time IDs are another way to create UIDs for your files. They are so popular because they can be easily generated (just look at a clock) and will always be unique. In addition people find the Time/Date aspect of it very helpful because they see their notes and topics in a temporal aspect. For example, you remember writing a bunch of notes on a topic in January of 2015. It becomes very easy to pull up all your notes from that time period. This strategy wouldn’t work well in a physical collection because notes that are thematically related are not together. You run into the same problem as note titles above.
Another way to approach time IDs to is the method employed by Zettlr and The Archive (I think, don’t have an apple computer to test it out). Zettlr allows you to either generate a Time ID in the title itself or anywhere in a document. Then when you go to search it just does a universal text search for that time ID and uses a ranking system to display the findings. This means showing notes with the time ID in the title first, then notes with it in the metadata, then notes that have it show up early in the note, followed by every other note that mentions it.
Left off: Other downsides to Time IDs?
UID Option 3: Sequential IDs
Sequential IDs are where you give each note a number and just a next highest number when adding a new note. This is the strategy that Zettelkasten^3 uses. Because it is all a digital system, using Luhmann IDs become unnecessary as you can easily pull up related notes through linking and the creation of custom note sequences. The main downside to sequential IDs is that they serve no secondary function. Zettelkasten solves the search problem (pulling up the note you want) through the use of tags (keywords) and related notes being connected. So if you want to find a note on “meta-memory” you’d either click on the meta-memory tag or find the most closely related note (psychology or metacognition) and click through the note links until you stumble upon it. The case for doing this instead of directly going to the note is it forces you to expose yourself to other notes which might induce an unexpected but useful insight.
UID Option 4: Luhmann IDs
Combining UID Types
Because UIDs are just characters/filenames, you can use multiple types of UIDs in a single file. I’ve seen people over on Zettelkasten De Forums who are championing the use of Time ID + Filename + Luhmann ID, so a note would be titled something like “202006011558 Metacognition 4d5a”. The purpose of doing this is it allows for one to use all the secondary functions/purposes. The alternative to this would be sticking to one title type, while embedding the other information in metadata at the top. An example of this is TiddlyWiki, where it allows you to see when a note was created and last modified.
Where I’m at with UIDs
I’m still trying to figure out what the best option is, as I only occasionally come back to this topic and think about it more. I only have so much time, so I’m trying not to spend too much on the question. So far I’ve settled on combining Time IDs with Titles, so in Obsidian this note is titled “202009141037 Unique Identifiers”. I’m still not entirely sure this is the best option as I lose the ability to have unmentioned backlinks. I’m hoping someday Obsidian will implement partial note title matches for unmentioned backlinks. The primary reason I am using both is it future proofs me if Obsidian doesn’t work out. This is the strategy that the folks over at The Archive use, and I tend to trust them because they’ve put a lot of time into creating a zettelkasten program. Take this with a grain of salt though because I haven’t entirely worked out why this is the preferred method. My current understanding is they do this because it serves as a redundancy in case something gets messed up with the note title. I will add a section after this if I gain further understanding.