The Solitude of Prime Numbers

The Solitude of Prime Numbers is a 2008 novel by Italian author Paolo Giordano. Set in Turin, Italy, novel tracks a young girl and boy, Alice Della Rocca and Mattia Balossino, as they come of age and experience their first years of independence. The story also explores their ongoing struggles with childhood trauma, which they survive by forging a strong emotional bond. Their identities are compared to prime numbers, indivisible and unique numbers that have intrinsic beauty but are untouchable by the numbers around them. The novel received the 2008 Strega Prize and was adapted into a 2010 film.

The novel begins when Alice and Mattia are seven years old. Alice’s father forces her to learn to ski, despite her protests and lack of skill in the sport. This denial of compassion becomes definitive of Alice’s relationship with her father. At ski lessons one morning, Alice loses track of the rest of her class. Afraid, and unable to navigate well on her own, she accidentally slides off a cliff, badly injuring herself. For the rest of her life, Alice lives with a physical disability. Mattia also has a difficult childhood, but for different reasons. His twin sister, Michela, has a severe cognitive disability. Because his peers and the surrounding community stigmatize Michela, they also shut him out of their lives. On an exceptional day, the twins are invited to the birthday party of a classmate. Mattia leaves Michela alone in a park near the party, fearful that his classmates will reject him if he brings her along. Michela disappears during the party and is never again found, despite the best efforts of the police.

The main characters’ respective traumas follow them throughout life, informing their future personalities and decisions. Alice develops an eating disorder and deals with a constant barrage of negative language about her disability. One particularly ruthless bully, a girl named Viola Bai, facetiously befriends Alice. Through her, Alice meets Mattia. At first, the two do not connect. Mattia spurns most extensions of friendship and engages in self-harming behavior. However, the two eventually form a strong bond. To their peers, they seem to be dating, but their relationship remains platonic throughout their youth. After high school, both go off to university. Alice studies only for a short time before dropping out to become a photographer; Mattia studies math. During this time, Alice’s mother, Fernanda, is diagnosed with cancer. While struggling to help her mother with her burden, Alice dates a doctor named Fabio Rovelli.



Mattia graduates from college and gets a job offer teaching math at a university on the Scandinavian Peninsula. However, he delays in accepting the offer because he does not want to split from his friend. In a dramatic scene, he tells Alice about what happened to Michela, and they have their first kiss. They do not take their relationship further than that. After Fernanda dies, Alice marries Fabio. Mattia accepts his job offer.

Alice’s marriage to Fabio does not last long. It falls apart over the subject of having children: Fabio wants one, but Alice is unable to get pregnant due to her eating disorder. After they split, Alice suffers from severe depression. Mattia excels at his job at the university. His colleague, Alberto, becomes his new best friend, and together they publish important work on algebraic topology. When they celebrate at Alberto’s home, Mattia connects to Alberto’s friend Nadia, and they have sex. In Italy, Alice’s boss recognizes her severe depression and brings her to a hospital. During her stay at the hospital, Alice notices a young woman with a severe cognitive disability and imagines that she might be Michela. She writes a letter to Mattia telling him to come home but does not give him a reason why.

Mattia returns to Italy at Alice’s request. Alice, however, doubts what she saw at the hospital, and never tells him why she sent for him. They spend part of a day together. Recognizing that she is still in love, Alice kisses Mattia. Yet, they both finally accept that their experiences are a gulf between them. The Solitude of Prime Numbers ends on the same theme of separateness and alienation with which it begins.