apologue

His introduction (‘An Apologue for an Epilogue’) is full of such outrageous nonsense as to suggest suspicion of his sanity.

The apologue is quite clear; and yet a certain amount of intelligence is necessary for its comprehension.

Rasselas is simply an extended and glorified moral apologue—an enlarged "Vision of Mirza."

No apologue addressed to the mature intelligence alone, or framed to fit the society of his day, is here included.