Rishi Kaneria examines the use of props in movies, from the sled in Citizen Kane to the oranges in The Godfather to the cardboard box in Se7en. A transcript is available here.
When used like this props become more than just objects. They become symbols. A symbol that represents a friendship. Or a marriage. Science. Or God.
A prop can be a symbol of reality. Or Illusion. Of the future. Or the past.
And the same prop can symbolize childhood in one film…but death in another. But death can also be symbolized like this. In the Godfather, Coppola associates death with something unexpected: oranges. This isn’t the kind of thing that’s in the foreground of filmmaking. But it’s there if you’re looking for it.