The concept of personhood (who is a person within a society) is the fundamental component of any selective concept of people. A distinction is maintained in philosophy and law between the notions "human being", or "man", and "person". The former refers to the species, while the latter refers to a rational agent (see, for example, John Locke's Essay concerning Human Understanding II 27 and Immanuel Kant's Introduction to the Metaphysic of Morals). Central issues of interest to people are the understanding of the human condition and the meaning of life, and survival. Religion, philosophy, and science show or represent modes and aspects of inquiry which attempt to investigate and understand the nature, behavior, and purpose of people. Sociology, economics, and politics represent modes by which people investigate how to maximize a collective survival strategy. Taken from: http://en.wikipedia.org/wiki/People