It is difficult, at first, to classify The Great Divorce. On the one hand it isn’t a non-fiction work of apologetics or theology. But on the other hand, the story is so slight that it hardly counts as a straightforward novel; certainly the narrative is much less involved than any part of the Cosmic Trilogy or the Chronicles of Narnia. I’ve decided that we can call it a fable, though it also bears some resemblance to the allegory of Lewis’ earlier The Pilgrim’s Regress. This question of just what genre to label a book is starting to seem a bit nitpicky, but it does have some import for how we end up reading and thinking about any book. Perhaps better than a label, however, would be a comparison to another book: Dante’s Divine Comedy.

Though nowhere near as long as that epic three-part poem, The Great Divorce does move through the same territory; it is a journey from Hell to Heaven, or more precisely a bus trip from “the grey town” to the green fields of the High Countries. Lewis based the book on the medieval notion that the damned will occasionally have ‘holidays’ from Hell. Whether part of the original idea or not, I don’t know, but Lewis also assumes that if they have holidays in Heaven, they probably also have the choice to stay.

Like Dante, Lewis puts himself into the tale, a witness to all that happens and is said, though not a direct participant. He is only dreaming rather than dead himself. Also like Dante the book is not simply about what happens when a person dies, or about describing that actual experience of either Hell or Heaven. It is instead partly a commentary on our life in the here and now, the way we live and the way we love. The book’s title is a response to William Blake’s The Marriage of Heaven and Hell, itself a rather radical work that argues we must have contrary and opposing forces in order to make progress. Lewis—overall a more conservative person—would rather we notice how nothing of Hell can remain in Heaven; how evil and sin must be rooted out in order for us to experience good and joy. In a sense a person must be unmade before they can be remade.

The first characteristic of the grey town Lewis writes of is its colourlessness. The streets seem empty and in fact the place looks deserted. There’s a sense of stagnation, ennui, leading to a kind of restlessness. We learn that people who come here end up quarrelling with their neighbours and move as far away from each other as they can. So the grey town ends up sprawling for millions of miles in every direction. People can have what they want simply by imagining it—not that it’s any good. The rain still leaks through the roof of your house. And the reason for this becomes clear when Lewis and the party of ‘daytrippers’ arrives in the High Countries.

The High Countries are real. So real that the people from the grey town are phantoms whose feet are hurt by the grass, who cannot pick a flower, and who “might fall to pieces at any moment if the light grew much stronger.” Some of the more shadowy people can barely be seen at all. But for all this they are welcomed by the solid, light-filled people who live in the High Countries and have come down to meet them—and if only they would choose to stay, and choose to travel towards the distant mountains, they would find themselves growing as solid as the world in which they stand.

This is the crux on which the book as a whole depends: choice. Anyone may choose how they’d like to live, how they’d like to feel, and what they’d like to love. Whatever Hell or Heaven actually are, they aren’t about getting our just desserts. There is no deserving anything; there is only the choice. As in Dante, the lesson is the need to love God above all others and above ourselves, to find in Him both the source and the answer of all our desires. You are only as real as what you love.

As I said, the narrative is slight. It largely consists of Lewis (the whole is written in the first person) observing the trip and listening to people’s conversations. He himself is a phantom and knows the pain of trying to walk on the grass. He even encounters his own guide: George MacDonald, who fulfills the same role as Virgil did for Dante. But there’s still a degree of separation between himself and the other characters. This is a dream after all, and a fable; dreamers are often more observers than participants, and fables exist for reasons other than dazzling us with plot mechanics. As long as you are willing to read a book that is working to an end beyond your entertainment, there’s much food for thought in these pages.