Born in Milan on 16 May 1718, Maria Gaetana Agnesi is considered to be the first woman in the Western world to have achieved a reputation in Mathematics (Britannica). In addition to being a mathematician, she was also a philosopher, theologian, and humanitarian who surprisingly left mathematics quite early in her life. 

Agnesi was born into a wealthy and literate family as the eldest of 21 children (including her half-siblings). Her father Pietro Agnesi was a prosperous silk merchant who married her mother  Anna Fortunato Brivio of the Brivius de Brokles family in 1717 to achieve nobility. Her family is believed to be one of the wealthiest in Milan at the time. Because of this, she could have access to enormous amount of resources and opportunities that many others couldn’t. 

The Seven-tongued Orator

From an early age, Agnesi had a remarkable ability to learn things. Her prodigious linguistic talent displayed her incredible intellect. By age 5, she could already speak both Italian and French. She added Greek, Hebrew, Spanish, German, and Latin to the list by the time she was 11. This famously earned her the nickname the” Seven-tongued Orator”. 

Along with linguistic prowess, she also displayed an extraordinary intellectual curiosity for philosophy. Seeing this, her father often organized gatherings in the house where she could present her ideas on various philosophical questions before some of the most learned men in Bologna. These discussions were published later in 1738 by her father in the book Propositiones philosophicae (“Propositions of Philosophy”). 

Mathematical Journey

Agnesi started Mathematics very early and was often found studying to the point it was considered excessive. She was already studying geometry and ballistics by the age of 14. But as she grew older, she was more and more inclined to theology and charity work and wanted to become a nun. Her father agreed to permit her to do all the charity she wanted as long as she pursued mathematical research and taught her siblings. Thus, she began avoiding all interactions with society and was entirely devoted to mathematics. 

Agnesi read de L’Hôpital’s Traité analytique des section coniques in 1739 and even wrote a commentary on it but it was never published. Around this time, she fortunately met a monk named Ramiro Rampinelli who was a mathematician and had even been a professor at both Rome and Bologna. He was a frequent visitor at Agnesi’s house and it was with him that she received proper instruction in the field, studying both differential and integral calculus. 

Rampinelli encouraged Agnesi to write a book on differential calculus. She wrote the book in Italian as a teaching text. With more inputs from other mathematicians and scholars, this book later took the form of Instituzioni analitiche ad uso della gioventù italiana (“Analytical Institutions for the Use of Italian Youth”) which included two huge volumes and integrated mathematical analysis with algebra. The treatise, however, contains no original Mathematics by Agnesi and rather contains carefully selected examples to illustrate ideas. Nonetheless, it was regarded as the best introduction extant to the works of Euler and made her very famous at the time. Recognizing her incredible Mathematical abilities and the credit her work could bring to Italy, Pope Benedict XIV appointed her as the honorary reader at the University of Bologna and was even invited to accept the chair of mathematics. However, it is unclear if she ever held the position. 

Witch of Agnesi

Her book includes a discussion of the cubic curve which is today known as the ‘witch of Agnesi’. However, she was not the one who gave the curve this name and there has been a lot of debate surrounding the reason behind it. The curve was discussed by Fermat and Grandi before 1703 where Grandi showed how to make the curve and in 1718, named it ‘versoria’. A Latin term that means ‘rope that turns a sail’. In Italian, he gave it the name “versiera’ and Agnesi later described it with the same name, calling it “la versiera”. However, when John Colson translated Agnesi’s work into English before 1760, he instead mistook it for “l’aversiera” and mistranslated the name. This “l’aversiera” in English means ‘the witch’ or ‘the she-devil’.

Later Life

After her father died in 1752, Agnesi left Mathematics and devoted herself entirely to charity and the study of theology. She worked for the poor, ill, and suffering and later also founded and directed  Opera Pia Trivulzio, a home for Milan’s elderly in 1783. She lived here until her death on 9 January 1799. 

Some Additional Facts

• She is considered to be the first woman to be offered a professorship in Mathematics at a university and the second to be offered a professorship at a university.
• Although some accounts claim her father was the professor of Mathematics at Bologna, it is entirely incorrect.
• Her sister Maria Teresa Agnesi Pinottini was a famous Italian composer. 
• Born in extreme wealth and prosperity, Agnesi died poor and was buried in a mass grave with fifteen other bodies. 

References

• https://en.wikipedia.org/wiki/Maria_Gaetana_Agnesi
• https://www.britannica.com/biography/Maria-Gaetana-Agnesi
• https://mathshistory.st-andrews.ac.uk/Biographies/Agnesi/ 

– Anuj Subedi