# Wang Zhenyi (astronomer)

Wang Zhenyi (simplified Chinese: 王贞仪; traditional Chinese: 王貞儀; pinyin: Wáng Zhēnyí; 1768–1797; styled Deqing(德卿), also known as the Jinling and Jiangning Lady Historian(金陵女史)), was a Chinese scientist from the Qing dynasty. Described as "an extraordinary woman of 18th century China", she pursued education in several subjects and is known for her contributions to astronomy, mathematics, and poetry.

## Biography

Wang's ancestral home was in Anhui province, and her grandfather's family later moved to Jiangning (Nanjing).
She was raised by her grandfather, grandmother, and father. Her grandfather Wang Zhefu (王者辅) was a governor of Fengcheng County and the Xuanhua District. He was an avid reader and maintained a large book collection. Her father, Wang Xichen, failed the imperial examination and turned to studying medical science, recorded his findings in a four-volume collection titled Yifang Yanchao (Collection of Medical Prescriptions). Her grandfather taught her astronomy, her grandmother taught her poetry; and her father taught her medicine, geography and mathematics.
From the age of nine, she was taught to write poetry and essays, focusing on the human condition. Her grandfather, Wang Zhefu, died in 1782 and the family traveled to Jilin (close to the Great Wall) for his funeral. Wang, along with her grandmother and her father, went to mourn outside the Great Wall and lived there for four years, where she studied under the Lady of Bu Qianyao. Here, Zhenyi gained knowledge from reading her grandfather's collection of books as well as learning equestrian skills, archery, and martial arts from the wife of a Mongolian general named Aa. She lived in Xuanhua Prefecture for five years. Later, she traveled with her grandmother and father to various places including Beijing, Shaanxi, Hubei, Guangdong, and Anhui. During these journeys, she visited numerous historical sites, gaining extensive experiences and exposure to various aspects of society.
At the age of 16, Wang traveled south of the Yangtze river with her father before moving back to the capital. She was able to see places like Shaanxi, Hubei, and Guangdong. When she was 18, she made friends with female scholars in Jiangning through her poetry and began focusing on her studies in astronomy and mathematics, most of which were self-taught. At age 25, she married Zhan Mei from Xuancheng in Anhui province. After her marriage, she became more well-known for her poetry and knowledge in mathematics and astronomy and taught some male students. Wang Zhenyi died at age 29 and had no children.

## Academic achievements

Although she only lived to be 29, Wang Zhenyi contributed to the academic study of astronomy and mathematics. One of her contributions was being able to describe her views of celestial phenomena in her paper Dispute of the Procession of the Equinoxes. She was able to explain and prove how equinoxes move and how to calculate their movement. She commented on the number of stars; the revolving direction of the sun, the moon, and the planets Venus, Jupiter, Mars, Mercury, and Saturn; as well as describing the relationship between lunar and solar eclipses. Not only did she study the research of other astronomers, but also conducted her own original research. At that time, there were few successors in the field of new astronomical calendrical knowledge. Moreover, due to the civil service examination system focusing on the eight-legged essay, scholars were disinclined to study natural sciences like calendrical astronomy, fearing its complexity and difficulty. As a result, calendrical astronomy nearly became a "lost art" of the era. Additionally, the restrictions on women learning calendrical astronomy were even more stringent, as it was deemed inappropriate for them to study in their seclusion. Despite this, Wang Zhenyi researched both Chinese and Western astronomy, and authored several works on the subject. Of her works, only about ten papers, including Explanation of Lunar Eclipses and Explanation of the Starry Sky, have survived.
Zhenyi's paper, The Explanation of the Pythagorean Theorem and Trigonometry, describes the Pythagorean theorem.
She admired the mathematician Mei Wending (1633–1721 A.D.), famous in the early Qing dynasty. Wang Zhenyi became a master of his book, Principles of Calculation, rewriting it with simpler language, and made it available to others under the title The Musts of Calculation. She was able to simplify multiplication and division to make learning mathematics easier for beginners. She was very dedicated in her study of mathematics and wrote a book called The Simple Principles of Calculation when she was 24. Her studies were difficult and she once said, "There were times that I had to put down my pen and sigh. But I love the subject, I do not give up."
Wang Zhenyi's Explanation of Lunar Eclipses analyzes the causes of lunar eclipses, with theories consistent with modern astronomical principles. In her work, she summarized various astronomical theories from Yu Xi to Guo Shoujing, and aligned them with Islamic, Western, and modern calendars. One of her experiments during this study included placing a round table in a garden pavilion, acting as a globe; she hung a crystal lamp on a cord from the ceiling beams, representing the sun. Then, on one side of the table, she had a round mirror like the moon. She moved these three objects as if they were the sun, earth, and moon according to astronomical principles. She corrected misunderstandings about the movement of celestial bodies and established the idea of the gradual shift of stars over time.
Wang Zhenyi also clarified concepts of calendrical epochs and methods, differentiating between the starting point of calendar creation and the methods of calculation, including arithmetic, diagrams, and instruments. She argued that changes in calendars across dynasties were about epochs, not methods.
In Theory of the Earth's Roundness, Wang Zhenyi refuted the thousand-year-old concept of a flat earth with a round sky, applying astronomical and geographical terms to advocate for the concept of a spherical Earth and revealing the idea of relative spatial positions.
Wang Zhenyi's contributions to medicine, although not encapsulated in a specific book, are evident in her prefaces to her father's medical works and her practical medical knowledge. She emphasized diagnostic precision, preventive medicine, and bespoke treatment strategies.

## Poetry

Her travel experiences, as well as her academic research, gave her plenty of ideas for her poetry. She left thirteen volumes of Ci (poetry), prose, and prefaces and postscripts written for other works. The famous Qing dynasty scholar Yuan Mei commented on Wang's poetry by saying it, "had the flavor of a great pen, not of a female poet". Zhenyi's poetry was known for its lack of flowery words, at the time believed to be common to feminine traits. Her poetry included her understanding of classics and history and experiences during her travels, such as sceneries and the lives of commoners with whom she made acquaintances.
Some examples of her work are:
“Transiting Tong Pass”
So important is the doorway, occupying the throat of the mountain Looking down from the heaven, The sun sees Yellow river streaming
“Climbing Tai Mountain”
Clouds overcast the hills, The sun bathes in the sea.
She also depicted the hard lives of commoners, especially those of laboring women in poems like “Woman Breeder of Silkworm” and “Clothes Washing.” In addition, she portrayed corruption and the polar contrast between the lives of the rich and poor in poems like “A Poem of Eight Lines,” which contained:
Village is empty of cooking smoke, Rich families let grains stored decay; In wormwood strewed pitiful starved bodies, Greedy officials yet push farm levying.
Wang Zhenyi's poetry is widely renowned for its simplicity, directness, and emotional depth. Her verses often reflect social realities, shedding light on the conditions and sentiments of her time. She utilized poetry as a medium to express her thoughts on various themes, including the status of women in society, the value of education, and her love for scientific inquiry. Her work is notable for its blend of traditional literary forms with progressive ideas, making her a unique voice in Qing Dynasty literature. Her poetic legacy, though partially preserved, remains a testament to her intellect, empathy, and pioneering spirit as a female scholar in a male-dominated era.

## Death

In the second year of the Jiaqing era, Wang Zhenyi suffered a relapse of malaria and became gravely ill. During her illness, she and her husband, Zhan Quan, reviewed her writings, destroying a significant portion and preserving only 20–30% of her work. Before her death, she entrusted her remaining manuscripts to her husband with instructions to deliver them to Madam Kuai, expressing her wish for commemoration after her death. A few years later, her husband Zhan Quan also died unexpectedly. The couple had no children.
Wang Zhenyi died in 1799 at the age of 29. The exact cause of her death is unknown. Aware of her impending death, she entrusted her works and manuscripts to her close friend Madam Kuai (1763–1827), who later passed them on to her nephew, Qian Yiji (1783–1850), a prominent scholar of the Qing dynasty. Qian Yiji compiled her writings into Shusuan Jiancun (Simple Principles of Calculation) and described Wang Zhenyi as "the number one female scholar after Ban Zhao".

## Legacy

During the Qing dynasty, it was exceedingly difficult for women to access education, particularly in fields such as astronomy, mathematics, and medicine, which were considered rare and specialized disciplines. Female scientists like Wang Zhenyi were extremely rare in feudal society. In the preface to Shusuan Jiancun, Qing scholar Qian Yiji likened her to Ban Zhao, a prominent female scholar of ancient China, praising her intellectual achievements. Wang Zhenyi was not only accomplished in the natural sciences but also progressive in her beliefs, dedicating herself to lifelong learning and advocating for women's education. She expressed dissatisfaction with the societal restrictions that denied women equal access to education, often protesting against norms that undervalued women in academics.
Her travels with her father broadened her horizons and deepened her intellectual curiosity, leading her to believe that "one's pursuit of learning knows no bounds, and every moment is precious." Despite her remarkable talents, her scientific work was often dismissed or misunderstood by her contemporaries, including her relatives, some of whom mocked her pursuits. Most of her scientific writings have been lost, with only a few general readership works surviving. Wang Zhenyi was recognized as a well-rounded scholar, excelling in literature, history, poetry, astronomy, and largely self-taught. Later scholars praised her as a versatile talent, proficient in both literary and martial arts, and unparalleled in her comprehensive knowledge of both Chinese and Western scientific methods.
Wang Zhenyi believed in equality and equal opportunity for both men and women. She wrote in one of her poems:
It's made to believe, Women are the same as Men; Are you not convinced, Daughters can also be heroic?
(Original quote: 始信须眉等巾帼，谁言儿女不英雄)
She believed social feudal values were inappropriate "when talking about learning and sciences, people thought of no women," she said that "women should only do cooking and sewing, and that they should not be bothered about writing articles for publication, studying history, composing poetry or doing calligraphy." [Men and women] "are all people, who have the same reason for studying."
In 1994, the International Astronomical Union's (IAU) Working Group for Planetary System Nomenclature approved naming a crater on Venus Wang Zhenyi after her.