“…… However, the teacher can give you a way to prove that on the planet we live on, in addition to the earth and the sea, sail on the sea by boat, sail from the land where the Ming Dynasty is located to the east, and sail all the way, and eventually come back from the west of the Ming Dynasty. ”

Yong'an County, where Qingshanzhai is located, is only separated from the sea by a Haifeng County, but even the adults of Qingshanzhai have never been to the seaside, let alone Fang Nan's students, fortunately, Fang Nan talked about the sea, rivers, boats and other terms last year, and now Fang Nan talks about these contents, and there is no need to explain them to the students again.

Under the existing conditions, it is impossible for Fang Nan to prove that he lives on a planet like the students, so Fang Nan just said the conclusion, and it didn't matter whether the students believed it or not.

With Fang Nan's teaching to the students in the past year, the students are very convinced of Fang Nan, although they can't believe that "the earth is a ball" now, but most of the students are trying to make themselves accept this conclusion, and some students plan to try to verify Fang Nan's conclusion if it is possible in the future.

After Fang Nan said the conclusion that "the earth is a ball", he continued to lecture the students on the relationship between the sun, the earth, and the moon.

"From our point of view, the sun and the moon seem to be very small, in fact, both of them are very big relative to us, in comparison with the earth we live in, the moon is smaller than the earth, and the sun is much, much bigger than the earth, why we see the sun and the moon are small, the reason is simple, the moon is far away from us, the sun is farther away from us."

"To give a very simple example, we look at the mountain in the distance at Qingshan Village, we all know that the mountain is very big, but in our eyes, the mountain is relatively small, and we can all take it in at a glance."

"All the time, the earth revolves around the sun, the moon revolves around the earth, and at the same time the earth revolves on itself, and when the sun's rays hit the area where we live on the earth, here is day, and vice versa, and in the earth or on this earth, day and night exist together."

"We don't dare to look directly when we look at the sun, the sunlight is very dazzling, but we can look directly when we look at the moon, the moon light is very soft, in fact, only the sun is shining and heating, the moon will not shine and heat, the moon reflects the sun's light to the earth, and the light reflected by the moon is very weak, in the daytime under the sun's light, we can hardly see the moon, and at night, there is no sunlight, you can see the moon."

"There are a lot of stars in the sky, do you know what the stars look like? In fact, the stars in the sky are the suns, and they emit light and come to the earth over a long, long distance, but they are farther away from the earth, so they look smaller. ”

"We have said that the sun, the moon, the earth, and the stars are left, and there are only two explanations for the sky, to say smaller, that is, a certain distance from the earth to the sky is the sky, and to say larger, the earth, the moon, the sun, and those stars are all in this 'sky', and this 'sky' can be called 'universe'."

……

Fang Nan said while fiddling with the mud ball on the lectern as a model, and the students behind him couldn't see clearly from a little distance, so Fang Nan asked the students to sit together in a dense manner, so that they could see the movements in Fang Nan's hands and see the changes in the model.

The change of day and night is easy to explain, and the change of the four seasons is a little more laborious, but in Fang Nan's explanation, the students have almost already understood.

Originally, many students still had difficulty accepting "the earth is a ball", but now that Fang Nan explained it, the reason for the change of day and night and the four seasons was found, and slowly they began to accept Teacher Fang Nan's statement in their hearts.

However, there is a point that the students are puzzled about, the earth is rotating, and people stand on the earth, if the earth side is facing down, how can people still stand on the earth?

Facing the doubts of the students, Fang Nan said with a smile:

"This question is the main content of the next general knowledge lesson, today I will briefly talk about it, I hold a mud ball in my right hand, my right hand is released, the mud ball falls down, we jump on the spot, and soon it will fall to the ground again, the fruit on the tree, if it is broken or ripe, it will fall to the ground, and so on.

These things are all a common principle, as long as you understand this principle, you can understand the question of 'people can stand firm on the earth', after school today, they can think about it, and tomorrow in the general knowledge class, I will listen to the idea first.

Okay, that's all for today's general knowledge lesson, let's get out of class. ”

Zhou Lei: "Stand up." ”

Suddenly, more than forty students in the school stood up and watched Fang Nan and Hu Xiaoya leave the school.

When the teacher left, the school suddenly became lively, and the students got together to discuss the content of the general knowledge class, and the content of the first general knowledge class really made their concept of the world change dramatically.

Originally, the students thought that the earth was flat, the sky was flat or like a big bowl upside down, but now in the air of Teacher Fang Nan, the earth is actually a sphere, and genius is truly boundless.

"Do you think the teacher is right?"

"It must be right, how could the teacher lie to us."

"Of course, the teacher won't lie to us, but the teacher knows if the thing will be fake, but the teacher will tell us as if it is true."

"The teacher's statement must be right, directly explain the alternation of day and night, the rotation of the four seasons, and what other statement can explain this clearly."

"Yes, yes, the teacher's statement is very reasonable, I believe the teacher's words."

There are still people among the students who can't fully believe Fang Nan's words, after all, these are all said by Fang Nan, but they can't get a valid proof, but more students still believe Fang Nan's words, or simply believe Fang Nan's words, or agree with Fang Nan's words in Fang Nan's explanation and fiddling model.

Anyway, after a common sense class, the students' mood has changed a lot, which is exactly what Fang Nan wants to see.

In the Ming Dynasty, how many poor scholars read and write, there is only one purpose, to take the imperial examination to become an official, "promotion to make a fortune" can be said to be deeply rooted in the hearts of the people, they want to get rid of the common people, promoted to become the ruling class, and then continue to oppress and exploit the people, and did not do much interesting things for the country, of course, the country itself has many problems.

Fang Nan wanted to break the inherent thinking of his students little by little, so that they could think more, such as why the earth is a ball, why people can stand firm on the earth, why the ruling class oppresses and exploits the people, and what should they do......