In his work "The Republic", Plato argues for the banishment of poets from his ideal state.
Plato’s ideal society was governed by philosopher-kings, who would legislate and rule, based on rational understanding and wisdom. He valued the role of legislators and philosophers much more highly than that of poets, whom he thought could undermine rational governance with their emotional influence.
In contrast, Percy Bysshe Shelley, in his defense of poetry, argued that poets play a crucial role in shaping and advancing society. By saying that poets are "unacknowledged legislators," Shelley is elevating the status of poets to that of those who shape and govern society, but in a different manner.
He argues that poets, through their creative and emotional influence, contribute to the moral and cultural development of mankind just as much, if not more, than the formal legislators who create laws.