In this chapter, we look at a number of disciplines that study human behavior, noting that the nature–nurture issue plays a central role in all of them, albeit leading to divergent views and controversies. I select some key disciplines, making no effort to be complete. My main goal is to show that every study of human behavior inevitably asks what the roles are of innate factors and of a variety of environmental factors, and how they interact. In all cases, we find defenders of more nativist/rationalist and more empiricist approaches. I will reiterate that this debate is not only relevant to academics: Views on the roles of nature and nurture have a direct impact on many aspects of daily human life. All people will sooner or later have to take a stance on issues that concern their own lives or the lives of others, including their children, parents, or friends. It is important to see how views that different people hold with respect to, for example, education and equality, are ultimately dependent on how they think (often subconsciously), or what biases they have, about human nature and human diversity.