Personal Knowledge Graphs

The Genesis of Personal Knowledge Graphs

The concept of Personal Knowledge Graphs is relatively new but has its roots in the broader field of Knowledge Management Systems. These systems have evolved over the years, from simple note-taking apps to complex platforms that allow for the interlinking of information. The video mentions that the first personal knowledge graph system was designed by a German sociologist named Luman in the 1970s. He used a simple shoebox and pieces of paper to create a system of interlinked nodes, effectively creating the first Personal Knowledge Graph.

Why Personal Knowledge Graphs Matter

Personal Knowledge Graphs are not just for tech giants like Google or insurance companies that collect data to optimize their services. They are for individuals who want to take control of their data and information. The graphs allow for a more natural representation of knowledge, making it easier to find connections and derive new insights.

The Evolution of Tools

First Generation

The first generation of tools focused on note-taking but lacked the ability to create relations between notes. Information was siloed in different apps, making it difficult to see the bigger picture.

Second Generation

The second generation, exemplified by tools like Roam Research, introduced the concept of links and backlinks. This allowed for the creation of a more interconnected graph of nodes, revolutionizing the way we think about note-taking and information management.

Notable apps

  • Roam research
  • Obsidian
  • logseq

Third Generation

The third generation, which is still emerging, aims to leverage artificial intelligence to work directly with the graph. This will allow for more complex queries and the ability to derive new information from existing relations. We have a big hope for AI agent that will help to create and mantain a PKG for user from a endless data streams. We have a too technical tools for Knowledge Graphs

  • RDF and Linked data
  • Semantic data

All this is powerful instruments but to technical for user.

To turn a Obsidian to a Third generation tool we just need to make Links first class citizens and give posibility to create a metadata for links .


I think exploring the relationship between modern PKM tools and ideas from the semantic web (RDF, SPARQL) is a interesting.

The semantic web didn’t lift off as much as some people had hoped, maybe because it is hard to make schemas uniform across different organizations. That makes it difficult to exploit semantic data despite our best efforts. Natural language based strategies (ChatGPT) have proven much more effective at this and do not require manual annotations. Also, semantic triplet databases required to exploit data from the semantic web have trouble scaling up to very large databases.

However, I agree that ideas from the semantic web could be useful within a vault. You see them popping up with the new frontmatter tools in Obsidian, as well as Tana and Anytype. They all add semantic labelling on top of notes.

One idea from the semantic web I tried to incorporate in my vault is the notion that a type is a URL. Lately I’ve been using the type key in my frontmatter that points to a note in my vault. That note describes what the type is, and how its content should be interpreted.

I disagree with your nomenclature: what you named Third generation tools have been around for much longer than the second generation tools, so using a temporal label could lead to confusion.


To turn a Obsidian to a Third generation tool we just need to make Links first class citizens and give posibility to create a metadata for links .

This is possible with some plugins. Typed links are a feature of the Jugl Plugin. However, for my purposes, I found that Excalibrain is sufficient and more accessible. You can acheive the effect of typed links by using tags.

2 Likes more about PKG

I did a small research and write an article Personal Knowledge Graphs in Obsidian | by Volodymyr Pavlyshyn | Mar, 2024 | Medium
I don’t why but discord community was not happy about it but it is few plugins that help to make PKG in obsidian

Personal knowledge graphs in Obsidian and Logseq

#personalinowledgegraph is used for a long times in enterprise. We want to shift it closer to a user day today life and give user a new tools.
Unfortunately market do not have easy to use tools for pkg for non professionals.
Let’s see how #obsidian or #logseq could help to make a first steps in this journey.
My humble opinion - we need #ai for a graph construction .
At we use #ai agents in tandem with personal knowledge graphs . Try future today

How to export your Obsidian Vault to RDF | by Volodymyr Pavlyshyn | Mar, 2024 | Medium now a way to convert vault to RDF

I am so happy to see this post!

I am about to publish an article How To that shows how I turned Obsidian into an open source intelligence analysis tool. The first part covers adding and using semantic data. It’s a limited use case but very powerful. For seasoned Obsidian geeks, you’ll be able to see how useful this can be and how flexible it is.