“There’s something to that,” Matthew says. “But maybe it’s time to grow out of that suspicion.” He reaches under the desk and takes out a book. It is thick, with a worn cover and frayed edges. On it is printed human biology. “It’s a little rudimentary, but this book helped to teach me what it is to be human,” he says. “To be such a complicated, mysterious piece of biological machinery, and more amazing still, to have the capacity to analyze that machinery! That is a special thing, unprecedented in all of evolutionary history. Our ability to know about ourselves and the world is what makes us human.” He hands me the book and turns back to the computer. I look down at the worn cover and run my fingers along the edge of the pages. He makes the acquisition of knowledge feel like a secret, b