Taleb may have repeated it, but the expression "the map is not the territory"[1] first appeared decades earlier in a paper by Alfred Korzybski[2], developer of the self-improvement movement known as general semantics[3].

[1]: https://en.wikipedia.org/wiki/Map%E2%80%93territory_relation

[2]: https://en.wikipedia.org/wiki/Alfred_Korzybski

[3]: https://en.wikipedia.org/wiki/General_semantics