περιφέρεια

The Greek noun περιφέρεια (periphéreia) is built from the preposition περί (perí, around, about, concerning) and the verb φέρω (phérō, to carry, to bear). The compound means literally 'the carrying-around' or 'that which carries itself around' — the sense of a line or boundary that encircles something by moving continuously around a central point. Phérō derives from the Proto-Indo-European root *bher- (to carry, to bear), the same root that gives Latin ferre (to carry), English 'bear' (in the carrying sense), 'ferry,' 'transfer,' 'offer,' 'prefer,' and 'suffer.' The preposition perí pervades Greek scientific vocabulary: it appears in 'perimeter' (perí + métron, measure), 'periphery' itself, 'perihelion' (perí + hēlios, sun — the point in an orbit closest to the sun), 'peripatetic' (perí + patein, to walk — literally 'walking-around,' the name for Aristotle's school because he lectured while walking), and dozens of other compounds. In Greek geometry, periphery was the technical term for what Latin called circulus — the circumference of a circle, the continuous curved line equidistant from a center.

The distinction between periphery (the curved boundary of a circle) and perimeter (the boundary of a polygon) was important in Greek geometry because these were fundamentally different kinds of boundary: a periphery is curved and continuous, a perimeter is angular and segmented. Archimedes, in his calculation of pi, exploited the tension between the two by inscribing and circumscribing polygons around and within a circle: as the number of sides increased, the perimeters of the polygons approached the periphery of the circle as a limit. This procedure — using the straight-sided perimeter to approach the curved periphery — was the foundation of a mathematical tradition that eventually became integral calculus. The word periphery thus names a concept at the center of the most important mathematical development between Archimedes and Newton.

The geographic and social extension of periphery — from the circumference of a circle to the outer regions of a country, empire, or organization — was already present in Greek usage. In the Athenian empire of the fifth century BCE, the 'peripheral' poleis were those at the edges of the sphere of Athenian power, the outlying city-states that paid tribute without wielding influence. The transfer of the geometric term to a spatial-political meaning preserved the essential relationship: just as the periphery of a circle is defined by and equidistant from a center, the peripheral region of an empire is defined by its distance from the political center. The metaphor works because it carries the geometric relationship intact into a new domain: center and periphery imply each other, and to call something peripheral is always implicitly to assert a center that it orbits.

In the twentieth century, 'periphery' became a key term in development economics and world-systems theory. Immanuel Wallerstein's world-systems analysis (developed from the 1970s onward) divides the global economy into 'core' and 'periphery' regions: the core consists of wealthy, industrialized nations with high-wage economies and complex economic structures; the periphery consists of nations supplying raw materials and cheap labor to the core. The dependency theory of the 1960s and 1970s had already formulated a similar center-periphery model of global economic relations, drawing on the spatial vocabulary of the ancient geometric term to describe a structure of domination. The Greek word for the circumference of a circle has become one of the central terms of the discourse about global inequality.