Book excerpt: "Introduction "Why do you do that?" "Why does our family insist on doing things that way?" Questions about people's behaviors are the essence of social science inquiry. The focus may be on individuals, families, social groups, communities, or cultures. To engage in the process of social science inquiry, you need two things: research and theory. Before we enter into a discussion of social science theory, specifically family theory, we first must have a discussion about theory in general"--