Rhine smoothly chatted with the surrounding Mermaids.
This "strange creature without a tail" briefly explained where they came from.
After simply asking a few questions and confirming that the Sea Country's general situation was not much different from what was in the book, he then lavishly praised the Sea King's power, complimented the splendor of the Sea King's Palace and gardens, and incidentally lauded the wisdom of the Sea King's mother, the Great-grandmother, and praised the beauty and nobility of the Mermaid Princesses.
He was so familiar with everything, not at all like a first-time visitor to the Sea Country, but rather like a guide who frequently traveled to and from it.
In no time, the Mermaids became quite familiar with Rhine.
They talked about everything under the sun. Rhine acted like those knowledgeable mages in stories, answering all the Mermaids' strange questions about the surface world one by one.
For example, one Mermaid asked:
"Why can the fish in your upper world swim even when not in water?"
Aurora was completely bewildered by this.
There were no fish in the human world that could "swim even when not in water"!
Rhine immediately told the little Mermaid:
"In the human world, we don't call those creatures fish—although they do fly overhead just like the fish here—instead, we call them 'birds.' Birds can fly because they have a pair of wings, and wings are to air as fish tails and fins are to water."
Aurora was instantly stunned, looking suspiciously at Rhine.
No, how did you know she was asking about birds?
Another little Mermaid asked:
"I heard from a friend who once went above the surface that in your world, the moon and stars are smaller but brighter than in our world. Why is that?"
"Do the moon and stars condense when they see you humans?"
What? The stars and moon in the Sea Country are bigger than those in the human world? Wait, are there stars and a moon in the Sea Country? Aren't they all in the sky? Aurora was completely confused.
Rhine smiled and patiently explained to the Mermaid:
"This is an optical illusion, caused by the refraction of light. In other words, your eyes are deceiving you."
When observing stars and the moon from the shallow sea, the light they emit is much fainter, but through a layer of water, the moon in the Mermaid's eyes appears much larger than in human eyes! (Note 1)
He even took out paper and pen on the spot, drawing light paths, angles of incidence, and angles of refraction, explaining the changes caused when light enters water, to illustrate the differences between the world seen through Mermaid eyes and human eyes, and the many problems arising from this difference in perspective.
Aurora barely understood the physics knowledge Rhine explained, both marveling at her teacher's vast knowledge and lamenting that the world held such deep secrets—what you see is not necessarily real.
But the Mermaids, who had never been to school, were utterly confused.
They just kept exclaiming in admiration, feeling that although they didn't understand it, it was incredibly impressive and must be profound knowledge.
The human youth talking to them must be a learned scholar from the upper world!
"So, even though we who live in the sea don't understand the humans of the upper world, humans understand us so well!"
"I thought we hadn't had much contact with humans. I thought humans knew nothing about us, about the Sea King, about this Sea Country, about the world through our eyes!"
"Human knowledge is truly profound and vast. Although I can't understand it, it seems incredibly powerful."
After chatting with Rhine, the Mermaids all exclaimed.
Seeing this scene, Aurora argued loudly in her heart:
"No, that's not right, it's not like that! Teacher cannot be taken as an example of humans!
"Most humans know nothing about the Mermaid's Country, nor would they study such wonderful knowledge or discuss the differences in perspective between Mermaids and humans."
Turning to look at Rhine, who was chatting happily with the Mermaids, Aurora was extremely puzzled.
Teacher, is this really your first time in the Sea Country?
As if aware of Aurora's confusion, Rhine explained while recalling:
"I once read a novel where the protagonist was a race living in the great sea. It provided the perspective and way sea creatures view the world, a different perspective from us humans.
"I precisely adopted the Mermaid's perspective and used their way to understand their questions.
"In the novel, the author compares schools of fish to birds—in fact, it's similar, just as humans look up and see flocks of birds of different colors flying by, Mermaids look up and can also see flying birds.
"The novel also said that the moon seen by sea creatures in shallow waters is much larger than what humans see!
"Many years ago, when I first read this passage, I was very surprised. I drew the light paths using my own knowledge and studied it for a long time before confirming that the author had not written it incorrectly."
The youth couldn't help but smile as he spoke, his eyes revealing memories and reluctance. This made him recall the years before he came to this continent.
After their questions were answered, the Mermaids curiously asked their "new friend without a tail":
"Humans from the land, why have you come to this sea?"
Rhine then stated his purpose:
"We are looking for a Sea Hag, a sea witch skilled in dark magic. We need her to help us with a small favor. You must know where she is, right?"
Upon hearing the two humans' purpose, the little Mermaids' expressions changed drastically, filled with alarm:
"No way?"
"They actually came to find that Sea Hag!"
"Does anyone really dare to look for her?"
"We Mermaids in the sea don't even dare to look for her! Are the humans from the land really that bold?"
"Don't go, absolutely not. She's a terrifying individual skilled in dark magic. Nothing good will come of asking her for help."
"..."
Note 1: Celestial bodies appear larger to Mermaids from underwater. At least, that's what Andersen said. I quickly imagined a refraction diagram for 10 seconds, and it seems to be true. If it's wrong, then it's Andersen's fault.