Prologue
The 48-Hour Window
Andrej Karpathy argued that AI should build persistent knowledge graphs instead of re-fetching RAG chunks every time.
It was a short post. No thread. No emoji. Just a grenade in a teacup.
For three years, the AI industry had duct-taped intelligence onto vector databases. The playbook was numbingly simple: chop your documents into chunks, squash them into floating-point vectors, and hope a cosine similarity search retrieves the right paragraph before the context window chokes. Chunk. Embed. Retrieve. Repeat.
Karpathy called the bluff. Memory isn't a cache you refill every prompt. Memory is a structure you inhabit.
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