What distinction did Friedrich Schiller make between naive and sentimental poetry?

In his celebrated essay Über naive und sentimentalische Dichtung (On Naive and Sentimental Poetry), Friedrich Schiller established a fundamental distinction between two types of poetic creativity.1

Schiller categorized poetry based on the poet's relationship to nature and the state of their own consciousness:

• Naive Poetry: This represents an immediate, unreflective state of being. The naive poet is in harmony with nature and their own senses; they do not experience a division between their inner self and the external world. This type of poetry is characterized by a direct, intuitive grasp of reality, often associated with the poets of classical antiquity.1
• Sentimental Poetry: This emerges when the poet has become separated from nature through the development of reason and reflection. The sentimental poet is conscious of this loss and seeks to restore the lost harmony through the power of the imagination. Because they are aware of the gap between the ideal and reality, their work is marked by reflection, longing, and a focus on the subjective experience of the poet.1

Schiller’s distinction was a significant contribution to aesthetics and helped define the transition from classical ideals to the reflective, subjective nature of modern and Romantic literature.12