Independence activist Lee Sang-seol (1870-1917) is the father of modern mathematics education in Korea. Yi Sang-seol believed that the key to the development of the Chosun national power to avoid imperialist aggression in the late 19th century lies in the learning and education of advanced Western studies, especially natural sciences. Thus, he began to learn most of the latest books in modern history and all of modern college literature by himself. He pioneered not only mathematics, but also western sciences such as botany, chemistry and physics, among which he wrote a botanical book called “Sikumulhak”, a chemistry book called “Hwahakgyemongcho”, and a physics book called “Baekseunghocho“.
In Baekseunghocho, Lee defines the concept, briefly summarizes the representative phenomena in everyday life and explains them. A brief introduction of some of the pictures and contents recorded in “Baekseunghocho” shall be as follows.”
“…when firewood is burned, it eventually disappears into shape, leaving only ashes, most of which are carbonated water vapor, etc. Prepare a glass cylinder as shown in Figure 2 and make a wooden disk underneath it, drill several holes in the plate and insert candles. Block the upper hole with a cork and drill a hole to insert the end of the U-shaped tube, while the other end of the tube is inserted into a larger U-shaped tube. Fill this bottle with caustic sodium that binds well with substances such as carbonated water vapor. First, measure the amount of caustic sodium, and then weigh a few seconds.
Light the candle and put it in the armor. After a while, turn off the light and weigh the candles again. The weight would have been slightly reduced, because it was burned immediately. Measure the weight of the soldier again and confirm that the weight has increased. This will be more than the weight of the candle has been reduced. When a candle burns, carbon combines with oxygen in the air to form carbonic acid, and hydrogen combines with oxygen to produce water, which is absorbed by caustic sodium NaOH through the tube. At this time, both carbon and hydrogen substances combine with oxygen to increase their mass, so there is no loss of hair when the substance burns….”
The above is an explanation of one of the fundamental laws of physics, ‘law of convention of mass’. The law states that the mass of a closed system remains the same regardless of state changes. Matter does not appear or disappear suddenly, but only changes in its form.
The book, which covered a wide range of content, contained the latest physics knowledge of Western high schools and universities at the time.
“Baekseungjocho” is the result of Lee’s passion and effort to understand and teach Western science. Most historians only record him as an independence activist. However, Lee Sang-seol’s true role in Korean history is that he is a pioneer who started modern mathematics and modern science education in Korea.