Tocqueville was a French sociologist and political theorist. He wrote Democracy in America after his trip to the United States, where he investigated the American prison system. The book is divided into two volumes, focusing on the structures of the American government and the institutions that helped maintain freedom in the country. Tocqueville believed that equality was the greatest political and social idea of his time, and saw America as the ideal realisation of an equal country. He applauds American individualism, but is wary of the dangers its extremity, known as atomism, could bring. He argues that some kind of social hierarchy is necessary for a productive relationship with the state.