This Substack post is amazing:

https://monistowl.substack.com/p/beyond-the-ladder

Quotes from “Beyond the Ladder

Vygotsky’s genius was to treat the mind not as a private museum but as a workshop with doors open to the street. Higher psychological functions arrive, initially, as relations, conducted with others by means of signs—most consequentially, language. The difference between a tool and a sign is crisp: a tool acts on the world; a sign acts on the self. The child’s first pointing is orchestrated socially: someone else directs attention and action. Through repetition in a cooperative frame, the child learns to direct their own attention; what was interpersonal becomes intrapersonal. This is internalization.

We will need three pieces from Vygotsky: (1) the notion that functions originate as social procedures before they become private resources; (2) the centrality of signs as levers by which a system can act on itself; and (3) the ZPD–MKO arrangement as the context in which reorganizations are made tractable rather than catastrophic.