Rhine smoothly struck up a conversation with the mermaids gathered around.
This "strange creature without a tail" briefly explained where they had come from.
After asking a few simple questions and confirming that the Sea Country was not too different from the one in the book, he lavishly praised the Sea King's might, extolled the splendor of the Sea King's Palace and gardens, commended the wisdom of the Sea King's mother, the Old Grandmother, and praised the beauty and nobility of the mermaid princesses.
He was completely at ease, not at all like a visitor entering the Sea Country for the first time. Instead, he seemed more like a guide who frequently traveled here.
Before long, the mermaids had become quite familiar with Rhine.
They chatted about everything under the sun. Rhine acted like one of those learned wizards from stories, answering the mermaids' strange questions about the world above one by one.
For example, one mermaid asked:
"Why can the fish in your upper world swim even when they are not in water?"
Aurora was completely baffled by that.
There were no fish in the human world that could "swim even when they were not in water"!
Rhine immediately told the little mermaid:
"In the human world, we do not call those creatures fish—although they do indeed pass overhead just like the fish here. We call them 'birds.' Birds can fly because they have a pair of wings. Wings are to air what tails and fins are to water."
Aurora was instantly stunned and looked at Rhine suspiciously.
Wait, how did you know she was asking about birds? Another little mermaid asked, "I heard from friends who have been above the sea that, in your world, the moon and stars are smaller than in ours, yet brighter. Why is that?
"Do the moon and stars compress themselves when they see you humans?"
What? The stars and moon in the underwater world were bigger than those in the human world? Wait, did the underwater world even have stars and a moon? Weren't they all in the sky? Aurora was utterly lost.
Rhine smiled and patiently explained to the mermaids, "It is an optical illusion caused by the refraction of light. In other words, your eyes have deceived you."
When viewing the stars and moon from the shallow sea, the light they gave off would be much fainter. Yet through a layer of water, the moon in a mermaid's eyes appeared far larger than it did in a human's eyes! (Note 1)
He even pulled out paper and pen on the spot, drew the path of light, the angle of incidence, and the angle of refraction, then explained the changes caused when light entered water. He used this to illustrate the difference between the world seen by mermaids and the world seen by humans, as well as the many issues caused by this difference in perspective.
Aurora barely managed to understand the physics Rhine was explaining. She was astonished by her teacher's vast knowledge, yet also struck by how deeply the world concealed its secrets—what one saw was not necessarily the truth.
But the mermaids, who had never gone to school, were thoroughly confused.
They could only keep marveling, feeling that although they could not understand it, it seemed incredibly impressive and had to be some profound form of knowledge.
The human boy talking with them was surely a highly learned scholar from the upper world! "So even though we who live in the sea do not understand the humans of the upper world, humans understand us so well!"
"I thought we had hardly interacted with humans. I thought humans knew nothing about us, about Sea King Your Majesty, about this country in the sea, or about the world as we see it!"
"Human knowledge is truly profound and vast. I cannot understand it, but it looks incredibly impressive."
After chatting with Rhine, the mermaids all sighed in amazement.
Seeing this, Aurora loudly protested in her heart, No, that is not right! Teacher cannot be used as an example of humanity!
Most humans know nothing about the mermaids' country, nor would they study such wondrous knowledge or discuss the differences between mermaids' and humans' perspectives.
Turning to look at Rhine, who was happily conversing with the mermaids, Aurora was deeply puzzled.
Teacher, was this really your first time in the Sea Country? As though he knew of Aurora's confusion, Rhine explained while recalling the past:
"I once read a novel whose protagonists were a race that lived in the sea. It offered the perspective and way of seeing the world held by sea creatures, a viewpoint different from that of us humans.
"I simply put myself in the mermaids' position and used their way of thinking to understand their questions.
"In the novel, the author compared schools of fish to birds—and in truth, they are indeed similar. Just as humans can look up and see flocks of birds of different colors flying overhead, mermaids can look up and see birds as well.
"The novel also said that the moon seen by sea creatures in shallow waters was far larger than the one humans saw!
"Many years ago, when I first read that part, I was quite surprised. I used my own knowledge to draw the path of light and studied it for a long time before confirming that the author had not made a mistake."
As he spoke, the boy could not help smiling. Reminiscence and reluctance showed in his eyes. It reminded him of the days before he came to this continent.
Once the mermaids' questions had been answered, they curiously asked this "new friend without a tail," "Humans from land, what have you come to this sea for?"
Rhine took the opportunity to state his purpose:
"We are looking for a Sea Hag. She is a sea witch proficient in Black Magic. We want to ask her for a small favor. You surely know where she is, right?"
When the little mermaids heard why the two humans had come, their expressions changed drastically. They were filled with shock and suspicion. "No way?"
"You actually came looking for that Sea Witch!"
"Someone really dares to seek her out?"
"We mermaids of the sea do not even dare to look for her! Humans from land are actually this bold?"
"Do not go! She is a terrifying creature proficient in Black Magic. Nothing good will come of asking her for help."
"..."
Note 1: Celestial bodies look larger to mermaids viewing them from the water. At least, that was what Andersen said. I spent ten seconds roughly visualizing a refraction diagram, and it seemed to work that way. If it is wrong, then it is Andersen's fault.
Before you continue