The Kang Yongqian prosperous era of the Qing Dynasty was the last "prosperous era" in China's feudal history. This era was initiated by the Kangxi Emperor and ended in the early years of Jiaqing, spanning more than a hundred years. During this period, there was no major turmoil in the country, and the people did not have too many disasters, and on the whole, they lived and worked in peace and contentment. Among them, the greatest credit should be the Kangxi Emperor, so he has the name of Saint Jun in history. However, this era is also a key era for the Chinese nation to turn from prosperity to decline, and after it passed, the backwardness of the Qing Dynasty in science and technology was highlighted, until it later moved towards a semi-feudal and semi-colonial society. Among them, the one who should be most responsible should definitely be the Qianlong Emperor. Therefore, some people think that Qianlong is a emperor. There is some truth to that. Why? Let's analyze it.

First, merit appraisal
Kangxi was the founder of The Prosperous Era of Kangqian, and he was the turning point figure who made the Qing Dynasty from a chaotic world to a prosperous world. In his time, he pacified san francisco to ensure national stability, recovered Taiwan to ensure territorial integrity, and the three conquests of Kaldan began the pace of the development of the Central Plains Dynasty to the west, so it is indeed a great merit. Moreover, the economic situation of the Kangxi affairs was relatively stable, and the emperor himself could restrain his selfish desires and not spend money indiscriminately. Although he has also been in Jiangnan six times, the overall scale is not very large, and the cost is not too much. Therefore, in the era of Kang Yongqian's prosperity, his construction role was even greater.
In this regard, Qianlong was much worse than the Kangxi Emperor. Nearly half of his ten martial arts skills were boastful. Although the general territory of today's China was established through the flattening of Jinchuan and the complete settlement of the Dzungars, it was generally inferior to that of Kangxi. The most fatal thing is that the Qianlong Emperor was so happy that he spent a lot of money on the south of the river and the yuanmingyuan, and squandered the money and wealth accumulated by the two generations of emperors of his father and ancestors. In his later years, he was even more greedy for tribute, and set off an unhealthy trend of collecting wealth and offering treasures in the imperial court. So that when it came to Jiaqing, the national economy was stretched, and the country went downhill. It can be said that qianlong single-handedly destroyed the prosperity of Kangqian, and naturally future generations criticized him.
Second, the scourge of culture
The prison of words was the biggest stain on the history of the Qing Dynasty, and it was a major maladministration of the Manchu Rulers who imprisoned people's minds. During the Kangxi period, the literal prison was not particularly powerful, and the major cases were only two cases, the "Ming Shi Case" and the "Nanshan Collection Case", of which the "Ming Shi Case" was still made by Ao Bai and other ministers who took care of his life, and had nothing to do with Kangxi. Therefore, in his time, the prison of words was not very powerful, and even Wang Fuzhi's "Reading through the Classics", which clearly wrote "Yi Di Annihilation is not unkind, taking it is not unrighteous, and tempting it is not unbelief", can be published. So the culture at that time was still relatively open.
The climax of the literal prison was during the Qianlong period. Qianlong has been in power for a total of 64 years, and more than 130 major cases of literary prison have been committed, on average once every six months. Among them, there is no shortage of extremely absurd cases such as the "One Pillar Building Poetry Case". After Qianlong's purges, the readers not only did not dare to say that the imperial court was not, but also let the emperor think that it was a twist and turn to satirize the imperial court.
In addition, Qianlong also used the name of repairing the "Four Libraries of the Whole Book" to wantonly destroy cultural classics, which was no less intense than Qin Shi Huang's "book burning pit Confucianism". Many later generations believe that the revision of the "Four Libraries of the Whole Book" is a major catastrophe in the history of Chinese culture. Therefore, many readers' criticism of Qianlong is very large, and his reputation is naturally not good.
Third, the scourge of science
In the late Ming and early Qing dynasties, Western science had undergone the Industrial Revolution and began to flourish. The reign of the Kangxi Emperor was an era of relatively rapid development after science entered China. Kangxi attached great importance to this new discipline, and taught himself mathematics, chemistry and astronomy. Two examples can be said: the Kangxi Emperor could dispense western medicine himself; at the time of the Three Expeditions to Kaldan, the Kangxi Emperor once took the time to make astral observations and compare the data with the emperor in Beijing. Although he did not make development science a national policy, he did have a hands-on attitude.
However, by the Qianlong period, the emperor had become "ignorant" again. The Qianlong Emperor was very dismissive of science, believing that it was nothing more than "kit kats". He was only interested in Western toys such as self-chiming bells and the Great Water Method, and did not seek much understanding of their principles. Moreover, his understanding of geography is also extremely lacking, and he does not even know where "English" is, this problem is not to say that the Kangxi era, that is, in the last years of the Ming Dynasty, in fact, it has been clarified. Therefore, Qianlong's understanding of science is a serious regression. It was because of this attitude that the Qing Dynasty as a whole moved toward ignorance, which eventually led to a serious decline in the level of science and technology and military strength, which led to China's humiliating modern history.
The above is just the most superficial comparison of the difference between the two. If you really want to dig deeper, the gap between the two people will be even greater. Generally speaking, Qianlong was an emperor with very ordinary abilities, whether in terms of political ability or personal cultivation, he was far worse than the two emperors of Kangxi and Yongzheng. All he had was luck, which allowed him to take over a thriving world. However, his ability really can't withstand this world, so that the prosperity will end and the decline begins. This is not only the sadness of him personally and the Qing Dynasty, but also the sorrow of the entire Chinese nation.