Bookmarked History of Philosophy - Summarized & Visualized by Deniz Cem ÖnduyguDeniz Cem Önduygu (
A summary of the history of philosophy showing the positive/negative connections between ideas
This could be thought of as a form of digital, single-project zettelkasten dedicated to philosophy. It’s got people, sources, and ideas which are cross linked in a Luhmann-sense (without numbering) though not in a topical index-sense.

Interestingly it has not only a spatial interface and shows spatial relationships between people and ideas over time using a timeline, but it also indicates—using colored links—the ideas of disagreement/contrast/refutation and agreement/similarity/expansion.

What other (digital) tools of thought provide these sorts of visualization affordances?