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Why a language gets grammar when nobody designs it: the iterated-learning experiment

Two 3 by 3 grids of two-part colour-coded words: random colours at generation 0, tidy rows and columns of repeated colours at generation 10
30seconds
The 30-second version

How does a language get grammar when nobody designs it? In a 2008 experiment, volunteers learned an alien language of 27 random words for pictures, saw only 14 of them, and then had to guess the rest. Their guesses became the next person's lesson, and so on down a chain of ten.

The random words slowly turned into patterns. Anything that could not be rebuilt from a few examples got lost, and anything that could be rebuilt got stronger. Run a toy version yourself: choose which words each learner sees, pass the language on, and watch noise turn into rules.

Deep dive · 4 min
Deep dive · 4 min

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