Demography (from prefix demo- from Ancient Greek δῆμος dēmos meaning "the people", and -graphy from γράφω graphō, implies "writing, description or measurement") is the statistical study of populations, especially human beings. As a very general science, it can analyze any kind of dynamic living population, i.e., one that changes over time or space (see population dynamics). Demography encompasses the study of the size, structure, and distribution of these populations, and spatial or temporal changes in them in response to birth, migration, aging, and death. Based on the demographic research of the earth, earth's population up to the year 2050 and 2100 can be estimated by demographers. Demographics are quantifiable characteristics of a given population.
Sociology is the scientific study of society, including patterns of social relationships, social interaction, and culture. It is a social science that uses various methods of empirical investigation and critical analysis to develop a body of knowledge about social order, acceptance, and change or social evolution. Many sociologists aim to conduct research that may be applied directly to social policy and welfare, while others focus primarily on refining the theoretical understanding of social processes. Subject matter ranges from the micro-sociology level of individual agency and interaction to the macro level of systems and the social structure.
Anyone who has studied psychology, sociology, anthropology, or any of the other wacko-and-wog disciplines knows the three great rules of the social sciences: Folks do lots of things. We don't know why. Test on Friday.
P.J. O'Rourke (2007) Age and Guile Beat Youth, Innocence, and a Bad Haircut. p. 207
The critique of Parsons exploded sociological theory into a thousand glittering but laughably parochial fragments of nano-theories. The contemporary culture of sociology is to treat social theory as set of personal expressions of literati and pseudo-philosophers. Surveying contemporary sociological theory is like going to the art museum. There we see lots of brilliant works, each the product of an artist's imagination. Certainly there is no attempt by artists to form a unified aesthetic vision. Nor should there be. But science is not art. A science becomes mature when the efforts of all researchers are coordinated by an underlying core model. This truth is denied in contemporary sociological culture.
Herbert Gintis, Review of An Invitation to Reflexive Sociology (December 6, 2009)