The so-called "learning from foreigners" mainly refers to learning a set of advantages of western capitalist countries in military technology, while "foreigners have three skills: one warship, two firearms and three training methods."

Wei Yuan not only advocated buying naval guns from the west, but also emphasized introducing advanced industrial technology from the west and manufacturing naval guns by himself. The so-called "controlling foreigners" means resisting aggression and defeating the enemy. In this proposition, learning from foreigners is the means and controlling foreigners is the purpose.

Historical background:

1840 the opium war broke out. Due to the defeat of the war, Wei Yuan was indignant and patriotic. 184 1 in March, he angrily abandoned his pen to join the army, joined the governor of the two rivers and the resistance general Yu Qian, and went to the front line of Dinghai to make suggestions.

1842, he wrote a 50-volume marine atlas. Why did the author compile this book? Wei Yuan made it very clear in the preface to the book Atlas of Sea Countries: "What is a book made of? It means "attack foreigners with foreigners, pay foreigners with foreigners, learn foreigners with foreigners, and control foreigners with foreigners." "

In other words, the purpose of writing a book is to understand "foreign feelings" and help people learn "long skills" to resist foreign aggression and inspire national prestige. This has given a slap in the face to the die-hards who are arrogant and regard the advanced science and technology in the West as "fantastic in their skills and taking advantage of it" and blindly exclusive. Wei Yuan pointed out in "Atlas of the Sea": "What is useful is strange skills rather than obscenity."

In dealing with foreign invaders, we should not "abandon their strengths and be willing to suffer", but "plug their weaknesses and take their strengths" Only those who are good at learning from the Four Foreigners can control the Four Foreigners.