Not quite -- it's certainly a famous related hypothetical/sub-problem, but the original is a much more fundamental point about human cognition being inherently representational.
The phrase was coined[0] by Alfred Korzybski who has some related stuff linked from his wiki page[1], though I'd give credit for the first+best modern explanation to Kant's work[2] on Sensibility (the first of four human cognitive faculties). I'm a Kantian cultist of sorts though, so take that with a grain of salt ;)
Certainly some would prefer to follow the idea all the way back to ancient Greece and/or China, or focus on more recent critiques of the concept by Hegel[3], Wittgenstein[4], or Deleuze[5]. I'm not a fan, but an even more (post-?)modern interpretation is Baudrillard's work on Simulacra.[6]
[0] https://en.wikipedia.org/wiki/Map%E2%80%93territory_relation
[1] https://en.wikipedia.org/wiki/Alfred_Korzybski
[2] https://plato.stanford.edu/entries/kant-spacetime/
[3] https://www.marxists.org/reference/archive/hegel/works/hl/hl...
[4] https://plato.stanford.edu/entries/wittgenstein/#PhilInve