We examine notions of universality and recursion in grammars, writing systems and the occurence of words, and find that they come in two main flavours: mechanistic and emergent. Preprints:202402.1330

What do universal Turing machines, universal spin models, NP completeness, top of a preorder and denseness of a subset have in common? They are all universal in a certain (precise) sense.

arXiv:2307.06851