In a 1968 interview, Johnson explained that he found mailed correspondence interesting because of the limits it puts on the usual back and forth interaction and negotiation that comprises communication between individuals. Correspondence is "a way to convey a message or a kind of idea to someone which is not verbal; it is not a confrontation of two people. It's an object which is opened in privacy, probably, and the message is looked at ... You look at the object and, depending on your degree of interest, it very directly gets across to you what is there".
