Pullman has been very articulate about his intentions for the three books as a whole.

They are to be "A rewriting of Milton's Paradise Lost," for young adults, and the first novel is Lyra's story. In the second, he introduces another focal character and the third novel involves them both in an epic struggle. In this work, the good people, like Lyra and her friends, are on the side of the fallen angels and humans and against the established educational, governmental and religious institutions of her society. Indeed, Pullman has designated Lyra as "The New Eve," whose coming-to-knowledge is essential for the fulfilling, self-determined life of all humans.

When she sets out on her quest, Lyra is eleven years old and does not even reach the age of twelve by the end of book one.

The whole story chronicles the transition from innocence to experience, or...