self-interest

The term "self-interest" is a transparent compound formed within English from two native elements. "Self," a core Germanic concept of identity and reflexivity, combines with "interest," which entered English via French from a Latin legal term denoting a compensatory stake or concern. The Latin root interesse literally meant "to be between," implying something that makes a difference to an individual. By the 17th century, "interest" had evolved to signify personal advantage or benefit. The fusion of "self" and "interest" thus logically creates a noun specifying a concern that is inherently one's own, capturing the concept of personal benefit as the central, driving concern, a notion central to philosophical and economic discourse on human motivation.

Structure: self (own) + interest (benefit) self: From Old English self, seolf, sylf, meaning "own, same." It is a pronoun used to form compound words indicating action directed back on the agent or inherent quality. interest: From Anglo-French interesse, from Medieval Latin interesse ("compensation for loss"), from Latin interesse ("to be between, make a difference, concern"), from inter- ("between") + esse ("to be"). In this compound, it functions as a noun meaning "benefit, advantage."