[PCMcGee1]

I have been told that "imagination" is a misnomer, much like "free will", it's an artifact of an observed phenomenon that has no actual basis in reality. We do not actually invent or imagine anything new, although we can conflate multiple memories into new forms, or even serendipitously discover things, we cannot actually invent any new ideas that we haven't been introduced to before. As an example, take the invention of the wheel. A tree falling over in a windstorm falls onto another tree that is already present, and as a result it begins to roll down a hill quite easily. This occurrence is observed by a human who later in time employs the principle to move a heavy object. The knowledge is preserved through language transfer, eventually developing into the "wheel" we know today.

[maximus-decimus]

If we assume you're right, that means dragons do exist because people can't imagine things they haven't experienced.

[PCMcGee1]

But, dragons do exist, only now we call them "dinosaurs".