According to the clue of the development of Confucianism, the Confucian tradition begins with the theory of "being expert, wise and knowing the natural principles" by Confucius, Mencius and Dong Zhongshu, and the Yijing revised by the theory of natural principles by Confucius and Dong Zhongshu, and ends with the theory of "everything is reasonable" by Confucianism and Zhu in Song Dynasty, and finally reaches the external principle of "know life reaches the natural principles" by Confucian scholars. In Confucius' place, it is both internal and external. On the one hand, Confucius turned the ceremony into the inner feelings of people in the category of "benevolence" and the moral requirements of the inner spirit, and inherited the thought of "people are only dangerous, the Tao is only subtle, and they are only fine, leaving them in a daze", which inspired Mencius to "know their nature to the best of his ability, and then to the well-known Confucian psychology of Lu Xiangshan and Wang Yangming; On the other hand, Confucius revised the ideas in Zhouyi and Yi Zhuan, that is, "it is easy to be consistent with heaven and earth, so we can learn the way of tomorrow", "Looking up, we can observe the astronomical phenomena, looking down, observing the culture of birds and animals and their suitability to the place, getting close to the body and taking everything far away, so we can open gossip to clarify the virtues of the gods and the feelings of all things". Therefore, saints should know the ambition of the world, set the industry of the world, and be suspicious of the sky. "Yi Fu, do things well and take the road of the world, that's all." This is to grasp the world from the external route of all things in heaven and earth ("easy to conform to heaven and earth, so we can learn the way of tomorrow"), and it requires "being kind to all things", "knowing the virtue of gods" and "making things happen" (science and industry). Just as Confucius said, "The world is the same but the Tao is different, and we are consistent and considerate", we can say that the internal route and external route of Confucian spiritual and cultural tradition are exactly "the world is the same but the Tao is different", that is, in the inner world and the external world, "exhaustion leads to destiny", which all point to the spiritual realm of heaven. Confucian spirit is trapped in the universe instead of being enslaved through the "heart", and seeks to gain experience, consciousness, understanding, knowledge, truth and aesthetics from inside and outside in the present reality, but it goes beyond them and pursues the supreme religious realm of "reaching the dawn". We will not get lost in the "delusion" of the mind, which transcends the fate of life and death. Rational spirit and spiritual consciousness exist. We look at the world in the realm of heaven, serve heaven, settle down, actively join the WTO, and achieve greatness. "Only when the world is sincere can we manage the great classics of the world, establish the foundation of the world and know the teaching of heaven and earth. How can a husband rely on things! If you are kind, you will have a deep origin and a broad sky. If you are not solid, you can know it! " (The Doctrine of the Mean). This is the classic expression of this realm.

The "saints" under the inner route are spiritual saints (saints under the psychological route), while the "saints" under the outer route are saints at work (saints of heavenly creations). Their "achievements" generally correspond to morality and science. This is the true state of "sanctification" under the Confucian cultural tradition, which is also the fundamental basis for why Confucianism can be called Confucianism (non-Christian Catholicism) as "heavenly religion". Its remarkable feature is that it does not have and does not need the concept of "original sin" like Christianity. Unlike Christianity, people like Jesus pretend to be messengers from heaven and preach to people in the name of God. It holds that people can know, comprehend and discover the will and secret of "Heaven" from the nature, principles, order and everything in the world in their own hearts, and obey and convert to "Heaven" in spirit (China people call death "Death in Heaven" and the so-called "Death in Heaven"). Sages and Confucius are properly regarded as "wise and knowledgeable" (the golden mean), so they just teach their spiritual realm, perception, understanding and knowledge to others as "teachers" who grasp the Tao, while others are just "friends with fate" under "all kinds of troubles" (freedom of thought). Under the concept that "God has a heaven that will always be called" (Zhang Zai's True Dream), anyone can explore ("explore"), know, understand and discover the laws and will of heaven, instead of pretending to be God to "preach" or communicating with God only through the church. This kind of religious characteristic extends to religion in the west. This is why ancient China was ahead of the world in many aspects, and Chinese civilization is considered as the most fundamental reason for the precocity of civilization. It should be noted that compared with the logicism (logical rationality) and epistemological tradition of western ancient Greece and Rome, China's cultural tradition is relatively weak in this respect and needs to be absorbed and used for reference. In fact, this is also an important reason why despite the above-mentioned important cultural background and potential possibilities, China has never succeeded in developing democracy, science and large industry in the modern sense, thus learning from the West in modern times, especially under the slogans of "May 4th Movement", "Mr. Sai" and "saving the country through industry". Under the spiritual structure of harmony between man and nature in China's cultural tradition, when people can make use of and rely on their own conscious spirituality, fully develop and learn from instrumental rationality and their own abilities, and pursue the spiritual realm of "reaching heaven and know life", under the profound religious spirit, morality ("benevolence, righteousness, courtesy, wisdom and trust"), science ("naturally creating things" and "teaching things"), art (The Bell of Love) If Confucianism can absorb Indian Buddhism and China Taoism, then the outside of Confucianism can absorb western learning, making China's Confucian cultural tradition the most inclusive and compatible in the world, while maintaining its own basic cultural characteristics and consistent cultural traditions. This is due to the great possibility of the spiritual line of internal and external cultivation and the spiritual structure of harmony between man and nature in the deep structure of Confucian cultural tradition. This should be the continuous ideological creation of modern neo-Confucianism. Today, it is time to systematically expound the modern neo-Confucian theory which is consistent, internally coordinated and eclectic, inherit the Confucian orthodoxy and open up the modernity of Confucianism. It is the fundamental reason that China tradition has tenacious vitality and the ability of cultural regeneration that "being big first, but being small can't be taken away".