What is meant by the 'traditional use of poetry'?

Explanation

Instruction through delight, fulfilling expectations shaped by past joys.

Note: Passage I, by Harold Bloom on the uses of poetry, is copyrighted and not reproduced. Bloom asks what use poetry can have when its true subject is the poet's own selfhood. The traditional use was instruction through delight, pleasure being the fulfilment of expectations shaped by past joys. A poetry of the self serves instead the psyche's need for self-recognition, from which originality springs.