Why Aristotle calls a human being a political animal?
Human beings are political animals because we live in the city-states where we share things among our species. Human beings are the only species who are capable of creating a city-state with political structure, political organisation. Therefore, human beings are distinct from all other species, because we do not only socialize but also create political life.
In his “Politics”, Aristotle writes: “The man who is isolated, who is unable to share in the benefits of political association or has no need to share because he is already self sufficient, is no part of the city, and must therefore be either a beast or a god.” (1253a25). So, Aristotle believes that man has different type of needs which he is not able to fulfill by himself - it is important to have something in common to share. For this reason humans form associations, starting by creating a family, then villages which grow into polis (state). The origin of polis is human political nature. Humans as political animals are determined to create political life, otherwise, as nature has not made man self-sufficient, man will not be able to fulfill all his needs. So having political life as inevitable - it is natural as well as necessary.
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