Hong Daeyong (; 12 May 1731 – 17 November 1783), styled Damheon (, "Relaxed house") was a philosopher, astronomer and mathematician of the late

Joseon Kingdom Joseon (; ; Middle Korean: 됴ᇢ〯션〮 Dyǒw syéon or 됴ᇢ〯션〯 Dyǒw syěon), officially the Great Joseon (; ), was the last dynastic kingdom of Korea, lasting just over 500 years. It was founded by Yi Seong-gye in July 1392 and re ...

. Hong was an early leader of the ''Profitable Usage and Benefiting the People'' () school of thought. It worked to promote the industrialization of his country and the development of trade by positively introducing Western technologies to Joseon Korea. Hong was a friend of Park Ji-won, who was another leader of the ''Profitable Usage'' school.

Early life

Hong Daeyong was born in 1731 in

Cheonan Cheonan (; 천안시, ''Cheonan-si''), also spelled Ch'ŏnan, is a city in South Chungcheong, South Korea. Cheonan has a population of 666,417 (2018), making it the most-populous city or county in South Chungcheong, and the third most-populous ci ...

South Chungcheong Province South Chungcheong Province ( ko, 충청남도, ''Chungcheongnam-do''), also known as Chungnam, is a province of South Korea. South Chungcheong has a population of 2,059,871 (2014) and has a geographic area of 8,204 km2 (3,168 sq mi) located in ...

. In his early days, Hong was educated by Kim One-hang of Seock-sil Seowon. During this period, traditional

Neo-Confucianism Neo-Confucianism (, often shortened to ''lǐxué'' 理學, literally "School of Principle") is a moral, ethical, and metaphysical Chinese philosophy Chinese philosophy originates in the Spring and Autumn period () and Wa ...

formed the basis of his academic world. In 1765, Hong followed his uncle Hong Eock(), who was in

Joseon missions to Imperial China The Korean state Joseon (1392–1897) sent numerous diplomatic missions to the Chinese states of Ming (1368–1644) and Qing (1636–1912). Joseon diplomacy A series diplomatic ventures illustrate the persistence of Joseon's ''sadae'' (serving th ...

. In China, Hong witnessed a brilliant development of

Qing Dynasty The Qing dynasty ( ), officially the Great Qing,, was a Manchu-led imperial dynasty of China and the last orthodox dynasty in Chinese history. It emerged from the Later Jin dynasty founded by the Jianzhou Jurchens, a Tungusic-speak ...

and experienced

culture shock Culture shock is an experience a person may have when one moves to a cultural environment which is different from one's own; it is also the personal disorientation a person may feel when experiencing an unfamiliar way of life due to immigration ...

. After returning to Joseon, Hong insisted enhancing the national prosperity.

Works

Hong was also interested in

astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...

and

mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...

. He maintained the rotundity of the Earth and

Earth's rotation Earth's rotation or Earth's spin is the rotation of planet Earth around its own Rotation around a fixed axis, axis, as well as changes in the orientation (geometry), orientation of the rotation axis in space. Earth rotates eastward, in retrograd ...

, which was rejected by Traditional Confucianists who thought the sky was globular and the ground was square. Also, He firmly rejected

Anthropocentrism Anthropocentrism (; ) is the belief that human beings are the central or most important entity in the universe. The term can be used interchangeably with humanocentrism, and some refer to the concept as human supremacy or human exceptionalism. F ...

, thinking all things in nature are equal. After failing the

Gwageo The ''gwageo'' or ''kwago'' were the national civil service examinations under the Goryeo and Joseon dynasties of Korea. Typically quite demanding, these tests measured candidates' ability of writing composition and knowledge of the Chinese cla ...

a few times, Hong gave up and became absorbed in astronomy research. He wrote '' Catechism of Eusan mountain''(), which contains the concepts of Earth's rotation and the equality among species and the infinity of

outer space Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, pred ...

. In mathematics, Hong wrote '' Interpretation and Usage of Mathematics''(). He also wrote '' Travel Essay of Yanjing in 1765 and 1766''(), a journal about his travel to China.

Crown Prince

In 1774, Hong was recommended for a mentor of Crown Prince, who afterwards would be

King Jeongjo Jeongjo of Joseon (28 October 1752 – 18 August 1800), personal name Yi San (Korean language, Korean: 이산; Hanja: 李祘), sometimes called Jeongjo the Great (Korean language, Korean: 정조대왕; Hanja: 正祖大王), was the 22nd monarc ...

. Hong discussed many topics and themes with crown prince. Although Crown Prince was satisfied with Hong's studies and polymathy, Hong found their difference of views among several topics and the conservatism of Prince. Crown prince demanded Hong to go into government service and be his own staff members, but Hong indicated his refusal in a roundabout way. Hong wrote '' Journal as the Mentor of Crown Prince''(), which contains their debate contents. After crown prince ascended the throne following the passing of the

King Yeongjo Yeongjo of Joseon (31 October 1694 – 22 April 1776), personal name Yi Geum (Korean: 이금, Hanja: 李昑), was the 21st monarch of the Joseon dynasty of Korea. He was the second son of King Sukjong, by his concubine Royal Noble Consort Suk ...

, Hong was appointed to local county governor. In there he tried to test his progressive ideas in local society. However, his mother's health condition deteriorated in 1782, so Hong abandoned a service and came back to Seoul. In 1783, mother regained her health, but Hong had a sudden

stroke A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...

. He wouldn't make it by morning, and breathed his last breath the next day. It was 23 October 1783(

Lunisolar calendar A lunisolar calendar is a calendar in many cultures, combining lunar calendars and solar calendars. The date of Lunisolar calendars therefore indicates both the Moon phase and the time of the solar year, that is the position of the Sun in the Ea ...

) as 17 November 1783(

Solar calendar A solar calendar is a calendar whose dates indicate the season or almost equivalently the apparent position of the Sun relative to the stars. The Gregorian calendar, widely accepted as a standard in the world, is an example of a solar calendar. T ...

Legacy

Hong's works, including ''Catechism of Ui mountain'', ''Interpretation and Usage of Mathematics'', ''Journal as the Mentor of Crown Prince'' were compiled to collection, '' Books of Relaxed House'' (). His practical Confucian ideas were succeeded by Park Ji-won and Park's disciples, but his scientific thought and research were succeeded by nobody.

References

External links

*
''Books of Relaxed House''
**
''Catechism of Ui Mountain''
**
''Journal as the Mentor of Crown Prince''
{{DEFAULTSORT:Hong Daeyong 18th-century Korean astronomers Korean Confucianists 1731 births 1783 deaths People from Cheonan 18th-century Korean poets 18th-century Korean scientists 18th-century Korean mathematicians 18th-century Korean philosophers Korean mathematicians