What metaphors are used in Symposium by Plato?

When the story is told about the two-faced human beings, this is difficult to be taken seriously. The reader is forced to decide if this is something serious or a joke. But again, when considering the Greek culture and the open acceptance of homosexuality, then most likely the story about the two-faced humans is a metaphor, which is intended to be taken seriously by the listeners. Often, a point can be made much more strongly by forcing a reader to recognize that it is an ironic point. The point made is opposite in some cases to what is openly said. The reader is forced to think and examine his or her own assumptions, instead of just taking every argument as reasonable at face value.