Language Log

This morning, by chance, I learned about the great urban center of Caral in Peru, 120 miles north of Lima.  It was occupied between ca. 26th century BC and 20th century BC and had more than 3,000 inhabitants.  It was said to be the oldest urban center in the Americas and the largest for the 3rd millennium BC.  Caral had many impressive architectural structures, including temples, an amphitheater, and pyramids that predate the Egyptian pyramids by approximately a century.

What attracted my attention the most, however, is this:

Among the artifacts found at Caral is a knotted textile piece that the excavators have labelled a quipu. They write that the artifact is evidence that the quipu record keeping system, a method involving knots tied in textiles that was brought to its highest development by the Inca Empire, was older than any archaeologist previously had determined. Evidence has emerged that the quipu also may have recorded logographic information in the same way writing does. Gary Urton has suggested that the quipus used a binary system that could record phonological or logographic data.

(source)

If not, what is it?  And how and why did people memorize it?

Responding to this post, "Memorizing a thesaurus" (10/28/20), Dan Martin remarks:

I found some of this discussion rather strange since to a kâvya* expert of the Indian and Tibetan realms (I am not one of them, although I got to hang with some of the great ones not so many years ago), this is a given: that the Amarakosha was never meant to be a dictionary for ordinary word meanings (.: absolutely not a Webster's), let alone a practical thesaurus for writers of expository prose (.: absolutely not a Roget's). It was meant, and went on to be used as such, as a resource for writers who wanted to write great poetry in the kâvya style. Even in Tibet, it was a way of 'Indianizing' your poetic output as was regarded as quite the hip, cool 'rad' thing to do until the mid 1980's (okay, for some self-styled modernists). I mean, maybe (who am I to judge?) it would have proven useless for Chinese literati who supposedly sinified everything they touched, but not so in Tibet.

Sounds like fun, doesn't it?

People actually did it in ancient India, and they still do it today.

Here are some passages from the Wikipedia article about the Amarakosha, the most celebrated and most often memorized Indian thesaurus.

Introduction

The Amarakosha (Devanagari: अमरकोशः, IAST: Amarakośa) is the popular name for Namalinganushasanam (Devanagari: नामलिङ्गानुशासनम्, IAST: Nāmaliṅgānuśāsanam) a thesaurus in Sanskrit written by the ancient Indian scholar Amarasimha. It may be the oldest extant kosha. The author himself mentions 18 prior works, but they have all been lost. There have been more than 40 commentaries on the Amarakosha.