Mathematical Genius: The Diary of Sophie Germain

January 10, 1790
Dear Diary,
I still cannot figure out that arithmetic problem that Archimedes left. Why can’t I get over the mystery of his death? It is something that I know I should not be wrapped up in, but I simply must find out what was so involving to him that he would die trying it. My parents, unfortunately for me, do not understand this longing of mine. I’ve been secretly studying at midnight. I hope they won’t ever find me out. Last week they made it clear that I was no longer allowed to study mathematics; however, I shall not ever give it up. Now I must get back to that example of Archimedes’s. What was so fascinating to him that he would die over it?

January 12, 1790
Dear Diary,
I think I have finally found a key to my problem. In mathematics, I mean. I tried telling mama today; well, I don’t mean to say I tried, I wasn’t even going to tell her, but I was so excited it simply slipped out. Therefore, she discovered my studying at midnight, when I should be asleep. When papa found out about it from mama, he took away all my lamplight. I’ll try candles tonight. But what has gotten into them, I wonder? I used to be allowed to study all the time, and now it is simply, “Sophie, don’t do this,” and “Sophie, don’t let me ever catch you doing that,” and so on and so forth, and it gets so tiring! I went into papa’s library early this morning when I was sure no one would be there, and there I found Bessie, the parlor maid, dusting away. When I checked further, she was actually asleep, much to my shock. And I noticed a cot bed in the corner. Has papa moved her to the library in order to stop me from studying? I brought the subject up with him at dinner, keeping back the fact that I had seen her at 2:00 this morning. He seemed rather guilty, but said nothing, much to my dismay.

January 13, 1790
Dear Diary,
In addition to my lamplight, my candles have all disappeared from my bedchamber- so I smuggled some stubs in from the dustbin in my shoe. I feel deceitful- but if only mama and papa would understand. I wonder what they would think if I showed them the solved arithmetic problem- pleased, proud, angry? Papa was extremely horrified when he found me studying one night. He insisted I have a maid in my room, but I sent her away with threat of dismissal, which worked pretty well, I must admit.

January 16, 1790
Dear Diary,
I feel as though I will never be able to figure out Archimedes. Maybe my parents are right. Maybe I am wasting my time! Anyway, my friend Pierre is coming today; perhaps he can cheer me up.

Later: Yes, Pierre did cheer me up, just as I thought. He and I both sneaked up into the school room and worked on my arithmetic problem. Pierre just breathes mathematics, and whenever I am around him, he seems to rub it off on me. There! I just crossed out my words from above. I’m never even going to start giving up again! Now, if only I could figure out this example….

January 17, 1790
Dear Diary,
I’ve DONE it! I’ve solved Archimedes’ death problem! It was actually really simple, if you can believe it- I can’t; some of his complex formulas are really too incompatible for me. But I’m ready. I’m going to take a chance and tell mama and papa my dream: to be a mathematician.

Later: Well, I gathered together my formulas, my diagrams and my courage, and went to my papa in the library. He fingered my work, scratched his head, and looked at me with a slight smile. I held my breath, and told him I was going to continue studying mathematics. “My daughter,” he mumbled to himself, “a mathematician? Possibly.” As he studied my equations though, papa’s smile grew and grew! “Fantastic!” he sputtered, “Sophie, you did all this yourself?” “I did,” I said to him, and went through the pages of formulas, explaining them to him. Though I knew he already knew them, it gave me great pleasure, and him as well.

And, do you know what else? Papa has given me full access to his library once more! Oh, I will study until I am a book; but why should I care?

March 14, 1790
Dear Diary,
Today Pierre came running in, out of breath and trembling with excitement. He told me his news, after very little coaxing. “Sophie! A group of scholars are opening a school! And the great mathematician Monsieur Lagrange will be teaching here in Paris! And I will get to be apart of it!” “That’s interesting,” I said to him, pretending insult. Pierre was too excited to care, though. “Sophie, did you not hear me? Isn’t it wonderful?” “Yes, I heard you,” I replied, and then tears came to my eyes. “But, Pierre, don’t you understand? I am a girl! As long as France looks on me as the ‘weaker sex,’ Pierre, I may never do mathematics out of my home- on penalty of rioting!” “Oh, I’m so sorry, Sophie,” he said, “but I have an idea,” the light returning to his eyes. I hardly understood what he meant at first, but now….


April 16, 1790
Dear Diary,
I tried Pierre’s idea. Over the past few weeks, I have been studying with Pierre and his friends; in other words, they have copied lecture notes for me, and shown me how to do the examples. And yesterday I prepared a paper for Monsieur Lagrange, and Pierre has smuggled it into the class and submitted it along with all the other papers. I am waiting for his news, with anxious mind and worried spirit.

Even worse: I have signed my name Monsieur LeBlanc. For some reason or other, I don’t believe a highly esteemed mathematician would read an essay signed, Sophie Germain.

April 17, 1790
Dear Diary,
Monsieur LeBlanc (myself) has passed the exam! And what else, for there is even greater news, is that Monsieur Lagrange wishes to meet me! But how? I am still only a girl; “For though I am but little, I am fierce,” as my papa quotes Shakespeare about me… fierce about arithmetic, he means. I am almost thinking about writing Monsieur Lagrange a letter of apology containing my true identity. Pierre says that Monsieur is impressed with my work, an even more wondrous compliment that I could ever have dreamed of. Hmmm. Perhaps I can meet him. An arranged meeting, perhaps?

April 18, 1790
Dear Diary,
My heart is still beating so fast I hardly know what to think. Monsieur Lagrange has been here! At my home! And was accompanied by Pierre~ that rascal~ I just knew his mind was working when he looked at me in that quizzical way of his yesterday. Pierre stayed after Monsieur Lagrange left, and told me the following:

“I told Monsieur about your being a lady mathematician. He was stunned, but was not in the least upset. He even promised to keep your secret!”

Monsieur Lagrange congratulated and moreover, he encouraged me to continue in my race. This will definitely be one of the most treasured moments of my life. I know that no universities will take me. But, God willing, I will continue to help all of Europe with my mathematics. You don’t think that last part was too proud, Diary, do you? Because I think I may make it smaller. I will continue to help all of France with my work. Oh, never mind! I will change all of Europe and the entire world. Perhaps… someday.

Signed,
Sophie Marie Germain
1790