What does it mean?
Even in very hard times, we can find some happiness if we choose to look for hope. The line is in the film, not the book.
Who said it?
Albus Dumbledore Source: Harry Potter and the Prisoner of Azkaban (2004).
Happiness– Albus Dumbledore, Harry Potter and the Prisoner of Azkaban (2004)
“Happiness can be found, even in the darkest of times, if one only remembers to turn on the light.”