Pirsig created the [Metaphysics of Quality]? (MOQ) to explain the connection between quality and morality with reality. Both books emphasise that the topic they are exploring cannot be precisely defined because of our limited experience. A parallel is trying to explain what lies outside an infinite universe - humanity struggles to understand how something can go on forever, let alone how there can be something beyond that. So each book takes the form of a semi-autobiographical story, mixing discussion of the topic with anecdotes and comparisons meant to highlight important aspects of the topic.
A [website] exists to discuss Pirsig's MOQ.