Accounts of the cosmic timeline have become common. What is apparent in all of them, besides the immense amount of time accounted for—approximately thirteen and a half billion years from beginning until now—are the different kinds of scientific explanation needed in each of the major stages. The initial stages are accounted for by astronomy and physics, until the development of life at which point biology and chemistry are the bases of knowledge, until the development of the human race. From then on, the social sciences become the bases of our knowledge including anthropology to describe the earliest stages of human life, psychology to explain individual human behavior, sociology to explain human social behavior, and economics to explain the material interactions of human society.