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Today, many people are building knowledge management systems to help them augment their thinking and learning. Whether they call it a second brain, zettelkasten, or (my favorite) knowledge garden, the objective is the same: building a place to store and evolve ideas over time.

While most of these ‘places’ center around ‘smart’ note-taking applications such as Notion, Obsidian, Roam, etc., they include other tools that support or integrate with these note-taking apps.

For example, my knowledge garden currently includes a central note-taking app (Obsidian) plus apps for advanced search and idea correlation (DEVONthink,) quick capture (Drafts,) managing citations (Bookends,) tracking commitments (OmniFocus,) and more. They all play a role, and I’ve found ways to integrate them.

There are lots of options for each system component. Which you select depends on your particular needs, and combining different elements makes your system unique. You want them to work well together. (I abide by Unix’s small pieces, loosely joined philosophy.)

Given so many choices, how do you select the right components? I can’t offer specific recommendations without knowing your particular needs. However, I can suggest baseline principles you should keep in mind. In particular, the components you pick should be trustworthy, open, and addressable. Let’s look at them in more detail.

Trustworthiness

One reason for capturing thoughts is to revisit them later. This implies keeping them in a stable place: you return after a while and find your notes as you left them. Barring physical damage such as fire or flooding, paper is outstanding in this regard. E.g., we still have Leonardo’s notebooks after five centuries.

Digital systems aren’t as stable. Applications and operating systems come and go, requiring constant upgrades and backups. Cloud-based apps can be more resilient in this regard but need continuous internet access. And the organizations that publish them are a potential risk for long-term access. (The company could go out of business or be acquired.)

System components should respect your privacy. The stuff you capture may be confidential or potentially embarrassing; you should only share your ideas intentionally. Look closely at the business model behind your system’s components: do you pay, or are you getting them ‘for free’? If the latter, how is the publisher supporting their ongoing operation?

Your knowledge garden extends your mind. Your thoughts won’t flow if you can’t trust the system. Don’t cheap out when selecting system components.

Openness

You can’t trust a system that keeps your information trapped. Look for features that allow you to export your stuff should you decide to switch. Is outgoing information saved in convenient, widely used formats? Can you export in bulk, or must you do it one item at a time? Be wary of apps that make it hard for you to move elsewhere.

Conversely, system components should also make data entry fast and easy. You should have as little friction as possible between ideation and capture. This is another advantage of taking notes on physical notebooks: paper requires no boot-up time and no fiddling with apps; you just put pen to paper and write.

To effectively extend your mind, your knowledge garden must allow you to enter flow states. It won’t happen if you’re constantly thinking about the mechanics of entering and exporting information into the system. Look for easy in, easy out.

Addressability

Links are foundational to a productive knowledge garden. You must be able to jump between related ideas, whether on paper (as in Luhmann’s Zettelkasten) or digitally, as in applications like Obsidian and DEVONthink. At a minimum, every item in your system should have a unique address (whether a web location or a link in your file system) that you can include in other notes.

Your system’s components should make using links quick and easy. Given that the web is almost three decades old, this should be a given. However, many note-taking apps — including some of the most popular — make linking between notes extremely difficult, if not impossible. Look for note-taking apps that treat intra-note links as first-class citizens.

Assume change

When people ask me about Duly Noted, I tell them it’s a book about ‘connected note-taking.’ Connected is the key. Links are at the heart of modern information management — links between ideas and between the apps that manage them. Your system will consist of several different components you must select with care.

Trustworthy, open, and addressable — abide by these principles, and you’ll pick apps that play well together and support your thinking over the long run. And it’s essential that you mind the long run since your needs and apps will change over time. Modularity and interoperability will serve you well as you grow a knowledge garden of your own.