Because when you apply Aristotle's Potatie Thereom, the horse becomes an enigma and therefore is not present in our visible universe. To determine why the horse was said, you must apply the Dog's Point of View in which all spaghetti appears to be a horse. Therefore, the horse was said because of the lack of pasta in the parabola.
I hope this answer helps.
+118613 Because it was Mr Ed and he really was a horse. That takes me back. Way before your time I would think.
https://www.youtube.com/watch?v=y_PZPpWTRTU&
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