"All relationships live in the shadow of the third, for it is the other that solders our dyad. In his book Monogamy, Adam Phillips writes, "The couple is a resistance to the intrusion of the third, but in order for it to last it is indispensable to have enemies. That is why the monogamous can't live without them. When we are two, we are together. In order to form a couple, we need to be three."