Accordingly identification or the formation of composite figures serves different purposes first to represent a feature both persons have in common secondly to represent a displaced common feature but thirdly to find expression for a common feature that is merely wished for. Since wishing it to be the case that two people have something in common is often the same as exchanging them this relation too is expressed in the dream by identification. In the dream of Irmas injection I wish to exchange this patient for another that is I wish that the other were my patient as Irma is the dream takes account of the wish in showing me a figure who is called Irma but who is examined in a posture in which I have only had occasion to see the other.