Jang Yeong-Sil

By: Matthew Jang

October 22, 2021

Humanities 9 – Eminent Person Project

“The advancement and diffusion of knowledge is the only guardian of true liberty.”

– James Madison

[A painting of Jang Yeong-sil]

            This year for my eminent person, I will be researching Jang Yeong-Sil. I chose Jang Yeong-sil because of his central role in advancing the Joseon Dynasty’s (now Korea) technology. For his many new inventions and improvements made to existing technologies, he is considered the finest of scientific minds of the Joseon Dynasty. While exceptional thinkers are not all too uncommon, I found Jang Yeong-sil’s upbringing/childhood interesting. Born into the peasant class, Jang Yeong-sil was an outcast in his society and failed to make friends. Without the presence of many friends in his life, Jang Yeong-sil turned to woodwork to find solace and was able to focus on the work he loved from a young age. This would open up the door for the young Jang Yeong-sil to become the figure he is today. Although it is hard to find a specific commonality between Jang Yeong-sil and me, Jang Yeong-sil was Korean like me. Being a Korean by ancestry, I grew up hearing stories of many different figures like Jang Yeong-sil. So, I have a sense of fondness towards him even though I never knew him. I admire Jang Yeong-sil’s creativity, resourcefulness, loyalty, and intelligence. However, the quality of Jang Yeong-sil I wish to emulate the most is his perseverance. As mentioned above, Jang Yeong-sil was born into the peasant class. He could work up the ranks thanks to King Sejong the Great, who believed that someone should be valued by ability and not hereditary. Jang Yeong-sil’s background caused the other officials and nobles to despise him and covet Jang Yeong-sil’s close relationship with King Sejong. Through all the hate he faced, Jang Yeong-sil continued to work tirelessly for his country and field. One could say that Jang Yeong-sil’s love for his work – especially his work in astronomy – bordered on obsession. Such characteristics of Jang Yeong-sil exemplify my own goals in TALONS as I wish to become a more self-driven and enthusiastic learner. I hope to become a self-driven individual and work out of love for my work as Jang Yeong-sil did. The vastly different times Jang Yeong-sil lived in compared to the modern-day makes it harder for me to connect with him. I also think the cultural differences in Korea and Canada, where I have lived my whole life, create boundaries. As is the case, I can research how daily life looked like in Jang Yeong-sil’s time. I can study social norms, political and religious ideologies to understand Jang Yeong-sil’s life better.

[A sundial created by Jang Yeong-sil]

            Jang Yeong-sil was a genius in his art and science, creating many inventions like the rain gauge, water clock, and sundial in Joseon. Jang Yeong-sil invented the first [well-known] rain gauge, called Cheugugi, in 1441. This was over two centuries before such a concept existed in Europe. While he worked to make time devices, Jang Yeong-sil was devoted to other scientific studies such as astronomy. Jang Yeong-sil’s first assignment from King Sejong was to create an armillary sphere to study the heavens. Jang Yeong-sil studied books written by Arabian and Chinese scholars who had made similar inventions. He then made his first armillary sphere, but Jang Yeong-sil would continue to improve on his design until he created an armillary sphere that could accurately read the skies. Such devices created by Jang Yeong-sil allowed scientists to create a calendar that recorded all the dates of heavenly phenomena. Beyond being an incredible invention, Jang Yeong-sil’s armillary spheres and other astronomical instruments were a sign of liberty and independence for the Joseon people. At the time, studying the heavens was a sign of power and something the Chinese emperor believed only China could do. This resulted in many of Jang Yeong-sil’s astronomical inventions being taken away or destroyed. However, Jang Yeong-sil inventing such instruments showed the people that they were not powerless and could achieve what was believed only emperors could accomplish. For this reason, I believe James Madison’s words hold true for Jang Yeong-sil. Jang Yeong-sil also helped Joseon by improving their weaponry. I believe that Jang Yeong-sil is worth studying because of his character, life, and inventions. Jang Yeong-sil has been remembered for over six hundred years in Korea, and I hope that he will become a more recognized figure in the future outside of Korea. I have no doubt that his work will influence and be remembered by Koreans at the very least for decades and centuries to come.

[Cheugugi – Rain Gauge created by Jang Yeong-sil]

[Self-Striking Water Clock made by Jang Yeong-sil]

Next Steps:

For the next phase of my research, I plan on looking deeper into Jang Yeong-sil’s inventions, how they worked, and their influence(s) on modern-day instruments used for similar purposes.

[A restoration model of Jeongnamilgu]