This is intended as a very abstract philosophical question.
Like Einstein with relativity was inspired by a man falling from a roof and a moving train. Most creative ideas seem to boil down to a person moving ideas across domains. Do you think this is always true even if the person is unwilling to admit the root thoughts, or perhaps they are completely unaware of the connections they subconsciously made? Is there truly a provably unique thought or is everything a product of experience?
If you invented something unique your first problem is going to be describing it to yourself. You’ll need new nomenclature. The second problem is describing the unique thing to someone else.
One could argue that anything that can be nailed down by language cannot be unique because the metaphors and phrases to describe it preexisted.