Dragons do exist. Throughout history, they’ve always been horned, four legged scaly beasts. Since the times of old though, they’ve gone through the process of evolution. It’s not the same kind of evolution that the birds and bugs undergo though. It’s the kind of evolution that humans have meddled with. But it’s not like the domestication of the dog or the selective breeding of sheep. It’s another kind of human influenced evolution.
If I say it was the power of words that made the dragon evolve, you might think it was the work of the Great Wizard of Magdabar. You might think that Magdabar stood upon a mountain, gathered the thunder and clouds, and uttered a spell to diminish the grandeur of the great beasts; shrinking them into shadows of their former selves.
In fact, it was almost completely the opposite. Dragons started out as feeble little urchins, and through the power of the word, they evolved into the fire-breathing beasts that we know of today.
The evolution occurred thus: ten thousand years hence, a hungry caveman was bitten by a water dragon. It hurt. “Like it had fire in its mouth.” The other cave-people spread word of the scaly beast with fire in its mouth. Like a fisherman’s tale, the sardine turned into a blue whale and the blue whale sprouted wings. By the time the Mesopotamians, the Greeks and the Vikings came around, entire religions had been built around the existence of dragons. The Catholic Church borrowed the Viking accounts, and the creature that had started as a glorified skink, had turned into the destroyer of worlds.
So, if you’re walking by the river and you see a dragon, feel free to speak of your courage to your comrades. You are in fact encountering the same beast, with fire in its mouth, that bit that caveman ten millennia ago.