What makes us human? Why do humans deal with the world in the ways that we do? The usual answer is that it is our intelligence. When it comes to intelligence, we believe we are special. When it comes to motivation, we believe we are basically the same as other animals. But human motivation is also special. This book describes why human motivation is special and how it makes us who we are. Humans want to experience that their feelings, beliefs, and concerns are shared by others. They want to experience that what matters to them about the world, what objects, events, and issues are worthy of attention, also matters to other people. And what humans share with others is what they experience to be real. It is a shared reality. This book tells the story of how our shared reality motivation defines who we are. It makes us strong as individuals and as groups. It can also tear us apart. Different modes of shared reality emerge during human childhood, and emerged during human evolution, that determine our experience of the world around us and how we deal with it. Our motivation to create shared realities determines how we talk to each other and remember the events in our lives. The story of shared reality is the story of how we feel, what we know, our attitudes and opinions, our sense of self, what we strive for and how we strive, and how we get along with others.