The theme of the book The Probability of Miracles by Wendy Wunder is positivity will let you do better things than negativity will. The day after Cam arrives at South Carolina, her and Lily go to the park to meet Lily’s boyfriend, Ryan. After getting to know Ryan, instead of feeling happy for Lily, Cam insists that he is using her. Cam didn’t feel happy for her friend, Lily, so she said her boyfriend was using her. Lily got angry because she knew what Cam said wasn’t true, and she wanted Cam to leave her alone because she wanted positivity, not negativity. Lily gets mad at Cam and wants Cam to leave her alone. If Cam had been happy for Lily, then Lily wouldn’t want Cam to stay away from her. Cam realized she had learned a little about hope, and was going to hold it out until her last wish came true. Cam found love before she died. Cam’s positivity helped her find love before she died. If Cam wasn’t being positive, then she wouldn’t have found love. Therefore, he theme of the book The Probability of Miracles by Wendy Wunder is positivity will let you do better things than negativity will.