You've probably heard of Niklas Luhmann and his fabled Zettelkasten. But there are in existence other even more influential card indexes with lessons for note-makers.

Aby Warburg was a German art historian obsessed with the connections he saw across European culture in the afterlife of Antiquity. He even coined a phrase: Verknüpfungszwang - the compulsion to seek connections.

Three projects display Warburg's extraordinary scholarly methods: his Zettelkasten, his libary and his visual atlas project, unfinished at his death in 1929. Taken together, these three amount to a technology for exploring Warburg's obsession with interconnection.

A thread through the labyrinth of thought

The first of these technologies is Warburg's Zettelkasten, his collection of index boxes, containing thousands of notes on various subjects.

"The slip box is Warburg's Ariadne's thread through his labyrinthine library like his labyrinthine thinking: from the werewolf to the historical concept. A thought, an idea or a new concept does not emerge in a linear progression, but in a process of reciprocating units of ideas and cross-references, which continues until new intersections and nodes have formed." - Benjamin Steiner, Aby Warburgs Zettelkasten Nr. 2 "Geschichtsauffassung", In: Heike Gfrereis / Ellen Strittmatter (Hrsg.): Zettelkästen. Maschinen der Phantasie (Marbacher Kataloge, 66). Marbach 2013, S. 154-161.

According to Fritz Saxl, Warburg's assistant and collaborator, "this vast card-index had a special quality... they had become part of his system and scholarly existence".

"Often one saw Warburg standing tired and distressed bent over his boxes with a packet of index cards, trying to ﬁnd for each one the best place within the system; it looked like a waste of energy. […] It took some time to realise that his aim was not bibliographical. This was his method of deﬁning the limits and contents of his scholarly world and the experience gained here became decisive in selecting books for the Library." - Fritz Saxl, The History of Warburg’s Library (1943-44, p. 329), quoted in Mnemonics, Mneme And Mnemosyne. Aby Warburg’s Theory Of Memory, Claudia Wedepohl (p.389).

A library of good neighbours and an atlas of images

The second technology of note is Warburg's library. He handed the family banking business to his younger brother Max, on the condition he could purchase any books he needed for his research into his true interest, art history. It may have seemed like a modest request, but Warburg's book collection grew ever larger and eventually expanded into a significant research library. It was arranged to maximize serendipity - fortunate encounters with neighbourly books.

The third technology for making connections was Warburg's visual Memosyne Atlas, intended to demonstrate in a series of large panels the lines of connection between artistic motifs in varying periods and locations.

Warburg's institutional legacy

Through his Zettelkasten, his library and his atlas of images, the compulsion to interconnect became Warburg's life's work. His institutional legacy, especially through London's Warburg Institute and Hamburg's Warburg-Haus, has proved extremely influential and highly intellectually fertile over many decades - and continues strongly into the Twenty-first Century.

In his novel The White Castle, Orhan Pamuk's narrator says: "I suppose that to see everything as connected with everything else is the addiction of our time." The life and legacy of Aby Warburg, shows that this doesn't have to be a pointless pursuit of arbitrary links but can generate lasting knowledge and meaning with wide implications.

Further information:

Aby Warburg’s Zettelkasten and the search for interconnection - a longer version of this article.

Introduction to the Warburg Institute Library and Collections - see the description of Warburg's Zettelkasten at 8:36

Aby Warburg: Metamorphosis and Memory - and Chris Aldridge's online notes on this documentary, which is how I found it.
Bookmark: reddit.com/r/Zettelkasten...

https://boffosocko.com/2023/05/06/some-notes-on-aby-warburg-metamorphosis-and-memory
https://warburg.sas.ac.uk/
https://warburg.sas.ac.uk/whats-on/news/exhibition-verkn%C3%BCpfungszwang
https://writingslowly.com/2023/05/09/aby-warburgs-three.html
https://www.academia.edu/30644838/MNEMONICS_MNEME_AND_MNEMOSYNE._ABY_WARBURG_S_THEORY_OF_MEMORY
https://www.academia.edu/8637204/Aby_Warburgs_Zettelkasten_Nr._2_Geschichtsauffassung_
https://www.kanopy.com/en/product/5913764?vp=lapl
https://www.warburg-haus.de/
https://www.youtube.com/watch?v=v9tgg57HnDQ