[thorel]

Some people trace the first exposition of recursive production rules for grammars back to Pāṇini (around 5th century BCE) [1]

[1] https://www.jstor.org/stable/23497283?seq=1

[shmerl]

Yep, it was also known to eastern mystics. And there is also a parallel in Sefer Yetzira about "stones" (letters) building "houses" (permutations), which also refers to such generative grammars.

[derefr]

Huh, I’m surprised some allusion to this didn’t come up in http://unsongbook.com/. Or maybe I just missed it!