If a browsing reader opened the book at random, I would hope they land on the first pages—the prologue with the mysterious love letter. That letter changed the way I understood Inge Lehmann. It is only one page. It is unsigned because the next page was missing. But its first lines open a door into a part of her life that has always been kept in the shadows. It begins:

My dear Inge, I am so excited; I can think of nothing but your letter… My uppermost thought is that I love you, and I want to make you happy.

Finding that letter was like hearing a seismic signal from her inner world—one she rarely shared with anyone. For a woman often described as solitary and private, the letter contradicts the myths about her, and perhaps also the broader myth that surrounds scientists. For me, it became a way to show that although scientists and geniuses may differ from the rest of us in many ways, they are still human, with all the complications and messiness that sometimes entails.

The second is the line that became the book’s title:

If I am right—and I know I am.

This sentence appears in a letter to Harold Jeffreys. It captures her whole spirit in one moment: doubt and confidence intertwined. Hurt and defiance. A lifetime of fighting to be taken seriously distilled into ten simple words. She wrote this when she was in her forties and as she was working on her groundbreaking discovery about the inner core. Knowing how much she had struggled to get this far it is a sentence that reveals her resilience and her growing confidence.

My hope is that this book brings Inge Lehmann into the place she deserves—both in scientific history and in public memory. She discovered something extraordinary, something every child learns in school. And yet her name is almost never mentioned. I want this book to change that.

I also hope the book highlights the human story behind scientific discovery. Lehmann’s work sits within a long chain of scientific quests carried out by a remarkable group of thinkers—many eccentric, many brilliant, many deeply flawed. The history of Earth science is dramatic, passionate, and sometimes tragic. I want readers to feel the intensity of that world.

This book is also a tribute to the quiet kind of genius. Lehmann was not a performer. She was not a self-promoter. She was cautious and reserved. She doubted herself. She struggled with mental health throughout her life. And yet she made one of the most important discoveries in geophysics. I hope her story encourages readers—especially younger readers—to see that scientific greatness does not require a perfect mind or a perfect life.

I also hope the book deepens public interest in Earth science. Understanding our planet is understanding something fundamental about the world we live in. Lehmann’s work reminds us that the Earth is dynamic, layered, and alive with movement. Beneath our feet is a world shaped by forces we are only beginning to understand. Her discovery was one piece of that puzzle, and I hope the book sparks curiosity about the rest. And finally, I hope readers simply enjoy the story. I hope they feel the tension, the vulnerability, the triumph, the mystery. I hope they close the book feeling that they have spent time with a real person—and that they carry her voice with them afterwards.