The books of the pre-Qin princes were mostly written in chapters at the beginning, such as "Han Feizi", which originally had "Lonely Anger" and "Five Worms", which were later assembled into books and named after Han Fei.

In addition, the process of writing the Book of Zhuzi is generally complicated, and its authors are generally accustomed to writing their own books, but from the perspective of its content, in fact, some of them are written by collecting the main sayings of their own school, and more are edited by their later disciples in the process of inheriting the master's lineage. In short, it may have been cultivated by many hands or compiled and supplemented over a long period of time. Because of this, the Book of Princes is often rumored and circulated, and some are mixed with other people's remarks. These reflect the characteristics of earlier literature.

In the history of Chinese academia, the pre-Qin period was a golden age in which hundreds of schools of thought contended and academic development flourished. The representatives of various families and many scholars have written books and lectures, or gathered disciples to give lectures, or questioned and debated, which not only left a precious cultural heritage for future generations, but also left a broad room for future generations to play and imagination.

Future generations should be better protected and inherited. The spirit and wisdom of the hundred schools of thought have influenced it to this day.

On the open-air terrace, a rare break.

Hua Feng and Yun Meng sat on the ground, saying something casually in this changing twilight of the sunset, until they sighed at the history of the earth.

"Xiaomeng, do you know how the earth we are going to protect now appeared in this cosmic space?"

"I just know one thing, it's still a vague kind. Brother Hua Feng knows?" Yun Meng and Hua Feng leaned together like dozens of couples, enjoying the tranquility of this stolen half a day's leisure.

"Listen to me tell you slowly......"

"The birth of the universe 15 billion years ago laid the material foundation for the creation of the earth. Earth as a planet originated from the primordial solar nebula 4.6 billion years ago.

Since then, the Earth system has evolved from simple to complex, with its components both interconnected and influencing each other. The movement of the earth system and the morphological changes, life phenomena and life activities brought about by the movement together constitute the history of the earth.

With regard to the formation of the solar system, one group believes that the solar system was the result of a drastic and accidental abrupt change, i.e., the catastrophic view, and the other group believes that the solar system evolved methodically and gradually, i.e., the evolutionary view.

In 1755, the German philosopher Immanuel Kant put forward a hypothesis for the formation of the solar system based on Newton's principle of universal gravitation, believing that the sun, planets and moons in the solar system were formed by the gradual evolution of nebulae, a thin cloud-like particulate matter. In 1796, the French astronomer Laplace also put forward the nebula theory similar to Kant, and later generations often combined the two to collectively refer to the "Kant-Laplace nebula theory". This hypothesis dominated for most of the 19th century.

The nebula theory holds that the formation of stars is a spherical fragment of the primordial nebula diffused by the Milky Way, which continues to shrink under the action of its own gravity, producing vortices, and the vortex causes the nebula to break into a large number of fragments, and each fragment gradually transforms into stars.

The sun is one of them, and it is constantly shrinking and rotating, forming the primordial sun in long-term motion. The surrounding objects continue to converge and collide, turning larger and larger, forming today's eight planets. In this way, the material around the planet gradually formed a satellite. This is one of the main hypotheses for the formation of the solar system.

Idealism holds that the earth and the entire universe were created by God or God's will. In the 18th century, an archbishop of Ireland openly declared: "The earth was created by God at 9 a.m. on a Sunday, October 23, 4004 B.C." "In ancient China, people believed that there was no heaven and earth in ancient times, and there was only a mass of qi in the universe, and 18,000 years ago, there was a Pangu clan who opened the heavens and the earth, and there were sun, moon, stars and earth.

Kant and Laplace believed that the solar system was formed by a large, rotating primordial nebula. The primordial nebula is composed of gases and solid particles that are constantly shrinking under its own gravitational pull. Most of the material in the nebula body aggregates into a primordial sun with a lot of mass.

At the same time, the rotation of the sparse particles around the primordial sun accelerates, and they concentrate on the equatorial plane of the primordial sun, and the density gradually increases. The material around the planet forms the moon in the same way. This is the Kant-Laplace nebula.

There are many hypotheses about the origin of the earth and the solar system, such as the collision theory, the tidal theory, the Big Bang universe theory, and so on. Since the 50s of the 20th century, these hypotheses have been increasingly questioned, and the nebula theory has risen to the top again. Many astronomers at home and abroad have not only made a general theoretical qualitative analysis of the origin of the earth and the solar system, but also discussed the formation process of the planets in quantitative and detailed terms, and they all believe that the origin of the earth and the solar system is the result of the evolution of the primitive nebula.

Chinese astronomer Dai Wensai believes that 5 billion years ago, there was a large nebula in the universe several times larger than the sun. On the one hand, this large nebula gradually shrinks under the influence of gravity, and on the other hand, there are many turbulent eddies inside the nebula. As a result, the large nebula gradually fragmented into many small nebulae, one of which was the predecessor of the solar system, called the "primordial nebula", also called the "solar nebula". Since the primordial nebula was formed in turbulent currents, it spun non-stop at the beginning.

The primordial nebula continued to shrink under the action of gravity, while its rotation accelerated, and its shape became more and more flattened, gradually forming a "nebula disk" on the equatorial plane.

The matter that makes up the nebula disk can be divided into "earth matter", "water matter", and "air matter". Under the action of gravity, these substances continue to shrink and aggregate, forming many "stars". The stars continue to accrete and annex, and the central part forms the primordial sun, forming a "planetary fetus" around the primordial sun. The primordial sun and planetary tires further evolved to form the sun and nine planets, which in turn formed the entire solar system.

Formation of the Earth:

The systematic scientific study of the question of the origin and evolution of the earth began in the middle of the eighteenth century, and several theories have been put forward to this day. The Earth, as a planet, is thought to have originated from the primordial solar nebula 4.6 billion years ago. Earth, like other planets, has undergone a number of common physical evolutionary processes, such as accretion and collision.

The material that formed the primitive Earth was mainly the primordial material of the nebula disk, the composition of which was mainly hydrogen and helium, which made up about 98% of the total mass. In addition, there is solid dust and material thrown out during the early shrinkage evolution phase of the sun.

In the process of the formation of the earth, due to the differentiation of matter, there are constantly light substances separated with volatile substances such as hydrogen and helium, and are carried to the outside of the solar system by the sun's light pressure and the materials thrown by the sun.

Mercury, Venus, and Mars, like Earth, may have formed in a similar way due to their proximity to the Sun, and they retain more heavy matter, while outer planets such as Jupiter and Saturn still retain more light matter due to their distance from the Sun.

Although there is still a great deal of speculation about the way in which the primitive earth was formed, most researchers agree with Mr. Devinsey's conclusion that after the formation of the above-mentioned nebula disk, due to the action of gravity and the instability of gravity, the material in the nebula disk, including the dust layer, formed many protoasteroids or stars due to collision accretion, and then gradually evolved and gathered into planets, and the earth was born in it.

It is estimated that the time required for the formation of the Earth is about 10 million to 100 million years, and the formation time of planets closer to the Sun (terrestrial planets) is shorter, and the farther away from the Sun is the longer the formation time, even up to hundreds of millions of years.

As for whether the primitive earth was hot or cold, scientists also have different theories. Proceeding from the ancient theory of the origin of the earth, most people once believed that the earth was originally a molten body, and that the earth still retains its heat after billions of years of geological evolution.

The results of modern research are more inclined to the theory of the origin of the earth's low temperatures. Whether the early state of the Earth was hot or cold is still debated. However, whether it is the theory of the origin of high temperature or the origin of low temperature, the earth has generally experienced a stage from heat to cold, and because the earth contains heat sources inside, this cooling process is extremely slow, and the earth is still in the process of continuing to cool.

When the earth was first formed, the temperature was relatively low and there was no layered structure, but later due to the bombardment of meteorites and other materials, radioactive decay and the gravitational contraction of the primitive earth, the temperature of the earth gradually increased, and finally became a viscous molten state. Under the rotation of the blazing fireball and the force of gravity, the material in the Earth's interior begins to diverge.

Heavier material gradually gathers in the center of the earth to form the core, lighter material is suspended on the surface of the earth to form the crust, and material in between forms the mantle. This gives rise to the so-called layered structure.

In the early days of Earth's evolution, the primordial atmosphere escaped.

However, as matter recombines and differentiates, various gases that were originally in the Earth's interior rise to the surface and become a new atmosphere. Due to the increase in the temperature of the earth's interior, the internal crystalline water is vaporized. Later, as the surface temperature gradually dropped, the gaseous water condensed, accumulated to a certain extent, and then fell back to the ground through rainfall, which lasted for a long time, so that a hydrosphere was formed on the ground.

The most primitive crust appeared about 4 billion years ago, and the Earth is bounded by its crustal appearance, which is called the astronomical period before the appearance of the crust, and after the emergence of the earth's crust enters the geological period. ”

"In this way, our appearance and the appearance of the earth are actually both accidental and inevitable?" Yun Meng's thoughts came back to his senses from being immersed in Hua Feng's voice.

Hua Feng nodded, his expression was indifferent, and his thoughts drifted to a long time ago.