Many Minds

String theories

Many Minds

Show Notes

Where would our species be without string? It's one of our most basic technologies—so basic that it's easy to overlook. But humans have used string—and its cousins rope, yarn, cordage, thread, etc.—for all kinds of purposes, stretching back tens of thousands of years. We've used it for knots and textiles and fishing nets and carrier bags and bow-strings and record-keeping devices. It's one of the most ubiquitous, flexible, and useful technologies we have. But we haven't only put string to practical purposes. We've also long used it to tickle our minds. My guest today is Dr. Roope Kaaronen. Roope is a cognitive anthropologist and postdoc at the University of Helsinki in Finland. Along with an interdisciplinary team, Roope recently conducted two studies that showcase the centrality of string in human culture. One is on the history and diversity of "string figures" (which are visual designs made with a loop of string held between the hands, often known to English speakers as "Cat's Cradle"). The other study is on the history and diversity of knots. Here Roope and I discuss the deep history of string in human culture. We talk about the seemingly universal spread of string figures across the globe. We zoom in on one string figure in particular—the Jacob's ladder—which seems to be the most widespread string figure of all, despite its complexity. We talk about how both knots and string figures are related to the branch of mathematics known as "topology," and about how knots and string figures have evolved under different constraints. Finally, we discuss what our fascination with string designs might tell us about the human mind. And we lament the fact that much of our string-based cultural heritage is headed—quite rapidly—for extinction. Just a reminder that applications are now open for the 2025 Diverse Intelligences Summer Institute or DISI. If you are an early career researcher and you like this show, you would probably like DISI. Actually, fun fact: our guest today, Roope, is a DISI alum. We met at the Institute a couple years ago and I've followed his work ever since. That should give you some flavor for the people who attend. In any case, for more info, check out disi.org—that's d-i-s-i. org. Alright friends, on to my conversation with Dr. Roope Kaaronen. Enjoy!

A transcript of this episode is available here.

Notes and links 3:00 – The 2020 paper reporting the use of string by Neanderthals. 8:00 – A paper describing the Antrea Net and its discovery. 10:00 – On the issue of gender bias in the study of textiles, see Virginia Postrel's book, The Fabric of Civilization. 12:00 – Dr. Kaaronen's other ethnomathematical projects include work on measurement across cultures. 16:30 – The website of the International String Figure Association. 19:30 – The 1969 paper first introducing the Standard Cross-Cultural Sample. 22:20 – A step-by-step explanation for how to make Jacob's Ladder. 30:30 – A step-by-step explanation for how to make the Swan. 38:00 – An example of a string figure that uses the Caroline Extension. 40:35 – A video demonstrating the string figure game of Cat's Cradle, which is played with a partner. 44:30 – A preprint of the knot study by Dr. Kaaronen and colleagues. 45:00 – The website of HRAF—the Human Relations Area Files—is here. 49:00 – A step-by-step explanation for how to make the knot known as the "sheet bend." 55:00 – An interactive article about what is known about Incan khipus. 59:30 – The "bible of knots" is the Ashley Book of Knots. 1:08:30 – An illustrated article on the so-called Austronesian expansion. 1:16:00 – An image of the ochre stone from 70,000 years ago, found at Blombos cave, featuring net-like imagery. A study finding sensitivity to abstract shapes in humans but not baboons.

Recommendations The Fabric of Civilization, by Virginia Postrel String Figures: A Study of Cat's Cradle in Many Lands, by Caroline Furness Jayne WhyKnot (YouTube channel)

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