Zettlekaste.de: Building a Second Brain and the Zettelkasten Method - This post goes into great detail contrasting the "Building a Second Brain" ideas of Tiago Forte and the Zettelkasten Method as practiced by Niklas Luhmann. The author states that both methods can be used simultaneously with little to no overlap (BASB is project focused, ZKM is knowledge-focused. It's worth the time to read!