When I point out that there is a vast amount of mathematics in The Simpsons, most people correctly guess that many of the most interesting equations are associated with Lisa, the supreme geek of The Simpson clan. For example, she has a book displaying Euler's equation in the episode "MoneyBART" and she uses geometry to help Bart improve his golf in "Dead Putting Society".
Hence, when a large of stack of benchess fall on Lisa in "Treehouse of Horror X", Principal Skinner cries out: "She's been crushed! . . . And so have the hopes of our mathletics team."
In my book "The Simpsons and Their Mathematical Secrets", I explain that all these references have been inserted by writers on The Simpsons who have strong mathematical backgrounds, including masters degrees and PhDs. However, one of the episodes that focusses on Lisa and mathematics ("Girls Just Want to Have Sums", 2006) was written by non-mathematician Matt Selman, who wanted to explore the issue of gender and mathematics.
In this episode, radical educationalist, Melanie Upfoot decides to protect Springfield's girls against prejudice by placing them in a separate school. At first, Lisa relishes the idea of an educational system that allows girls to flourish, but the reality is that Ms. Upfoot wants to indoctrinate her girls with a form of feminist mathematics.
According to Ms. Upfoot, girls should be taught mathematics in a much more emotional manner: "How do numbers make you feel? What does a plus sign smell like? Is the number seven odd, or just different?"
After becoming frustrated by her new teacher, Lisa asks if the girls' class is ever going to tackle any real mathematical problems. Ms. Upfoot replies: "Problems? That's how men see math, something to be attacked. Something to be figured out."
In the end, Lisa disguises herself as Jake Boyman, joins the lesson intended for boys, and proves that she is the best mathematician in the class. When she reveals her true identity, this causes fellow student Dolph Starbeam to exclaim: "We've been Yentled!"
On Ada Lovelace Day, when we remember some of the great mathematical breakthroughs made by women, it is worth noting that Lisa's storyline has much in common with the French mathematician Sophie Germain. Incredibly, the facts of Germain's battle against sexism are even stranger than the fictional narratives of Lisa and Yentl.
Born in Paris in 1776, Germain's obsession with mathematics began when she chanced upon an essay about Archimedes. Legend has it that Archimedes was busy drawing geometric figures in the sand when the Roman army invaded Syracuse in 212 B.C. Indeed, he was so obsessed with his shapes that he ignored an approaching Roman soldier. Offended by the apparent rudeness, the soldier raised his spear and stabbed Archimedes to death.
Germain found the story inspiring; mathematics had to be fascinating if it could spellbind someone to such an extent that he might ignore threats to his own life. As a result, Germain began to study mathematics all day and night. According to a family friend, her father confiscated her candles to discourage her from studying when she should have been sleeping.
At the age of twenty-eight, Germain decided that she wanted to attend the newly opened Ecole Polytechnique in Paris. The stumbling block was that this prestigious institution would only admit male students. However, Germain found a way around this problem when she learned that the college made its lecture notes publicly available and even encouraged outsiders to submit observations on these notes.
This generous gesture was intended for gentlemen, so Germain simply adopted a male pseudonym, Monsieur LeBlanc. In this way, she obtained the notes and began submitting insightful observations to one of the tutors, Joseph-Louis Lagrange, one of the world's most respected mathematicians.
Lagrange was so astonished by the brilliance of Monsieur LeBlanc that he demanded to meet this new student, which forced Germain to own up to her deception. Although she feared he would be angry with her, Lagrange was actually pleasantly surprised to discover that Monsieur LeBlanc was a mademoiselle, and he gave Germain his blessing to continue with her studies.
Over the next few decades, she made major contributions to both mathematics and physics, receiving a medal from the Institut de France and becoming the first woman who was not a wife of a member to attend lectures at the Academy of Sciences.
Just like Lisa Simpson, Germain had adopted a male identity in order to study mathematics. So, instead of shouting out "We've been Yentled!", it would have been more germane if Lisa's classmate had shouted out "We've been Germained!"
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