“Expecto Patronum”: Light/Darkness Imagery in Harry Potter

One of the most beautiful pieces of imagery in Harry Potter, that of the Patronus charm overcoming the dementors, is found in The Prisoner of Azkaban. Harry discovers that the dementors are attracted to him in particular:

“The dementors affect you worse than others because there are horrors in your past that others don’t have…Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope, and happiness out of the air around them.” (PoA 187)

Dementors “suck the happiness out of a place”; those who encounter dementors feel like as if they would “never be happy again.” Professor Lupin teaches Harry the Patronus charm, which “is a kind of positive force, a projection of the very things that the dementor feeds upon – hope, happiness, the desire to survive – but it cannot feel despair, as real humans can, so the dementors can’t hurt it” (PoA 237). One conjurs a Patronus by thinking of a very happy memory and focusing on it, allowing the memory to fill one’s thoughts.¹

The imagery here is truly beautiful (especially in the film version of The Prisoner of Azkaban), and, I think, can be accurately applied to the very real battle between good and evil. Dementors – dark and evil creatures that spread sorrow and despair – are overcome by the blinding light of the Patronus. Warmth invades the icy cold,² light enters into the darkness and defeats it, joy triumphs over sorrow. The presentation of evil is of an evil that is absolute, real, and truly horrible. Good is victorious over evil.<sup>3

1</sup> Philippians 4:8 comes to mind: “Whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things.”
² Similar imagery is found in The Half-Blood Prince, when Dumbledore and Harry are in danger of the Inferi. Dumbledore describes how these creatures, which dwell in cold and darkness, fear light and warmth (HBP 566) and can be fought back with fire.
³ We ought not to take for granted that good is portrayed as very good and very real, and evil as very evil and very real. This too reflects the objective reality of good and evil in our world.