Eudora Welty’s central theme in all of her work might be the separation that lies between human minds. One person can never know precisely what is going on in the mind (consciousness or psychic system) of another person because each mind is operationally closed. Love and friendship represent the willingness to understand even if complete understanding is out of reach. The following is a passage from Welty’s short story titled “The Key.”
And you knew that she would sit and brood over this as over their conversations together, about every misunderstanding, every discussion, sometimes even about some agreement between them that had been all settled–even about the secret and proper separation that lies between a man and a woman, the thing that makes them what they are in themselves, their secret life, their memory of the past, their childhood, their dreams. This to Ellie was unhappiness. (The Collected Stories of Eudora Welty, 36)
This strikes me as a great description of double contingency, which means that in any communication the two participants (alter and ego) cannot know what the other is going to say or do, or whether they will accept or reject the offer to continue the communication. Each participant is free, at any moment, to respond in a totally unexpected way or to reject the offer and walk away. We can say that alter and ego are black boxes to each other in the sense that one system (such as a psychic system or mind) cannot know what is going on within another system. The systems are operatively closed to one another. The two systems can irritate each other, but cannot force a particular response from the other system.
In an interaction system, two psychic systems structurally couple. This does not mean that the two systems unite; they maintain their separateness. The communication is its own system, and the psychic systems remain in the interaction system’s environment. The two psychic systems are also not subsystems of the interaction system because no system is a whole consisting of parts.
In other words, social systems do not consist of human beings.