Energeia

Energeia is a term from ancient Greek philosophy, commonly translated as “activity,” “actuality,” or “being in act.” It stands in contrast to dynamis (potentiality). In Aristotelian metaphysics, energeia refers to the actuality by which a thing fulfills its nature; it is the realization of form in matter. This concept helps explain how change and growth occur: substances move from potentiality toward actuality through causes and intrinsic form. The term is often paired with entelecheia (complete actuality or realized end), though the two terms are distinct: energeia emphasizes active realization, while entelecheia stresses the inherent end or purpose being realized.

Etymology and terminology: energeia derives from Greek en- “in” and erg- “work.” The word was transmitted into Latin and later into European languages, eventually giving rise to the English “energy” and related terms such as “energetics.” In Aristotle, energeia is not merely physical work but the in-acting of a thing being fully, actually what it is.

Medieval and modern reception: The concept was influential in Christian theology and scholastic philosophy, where energeia or “operation” was used to describe God’s active presence in creation and the intelligible operations of beings. In scholastic contexts, it helps distinguish God’s actual operations from mere potentiality. In contemporary philosophy of mind and metaphysics, energeia is mainly discussed as a historical term illustrating actualization and the nature of being, rather than as a technical term in empirical science.