Aristotle's Poetics introduced the concept that a well-formed plot must have a beginning, middle, and end, with each section logically following from the previous. Specifically, the beginning introduces elements without necessitating what comes before, the middle logically follows from the beginning, and the end logically follows from the middle in a way that provides resolution without necessitating anything further. This theory formed the basis of dramatic structure and was one of the earliest works of literary theory.