" With the intercom they could wander far apart from each other and still converse, and no one could know they were talking, while each voice hung in the other's ear. So they talked and talked. Everyone has had conversations that have been crucial in their lives: clarity of expression, quickness of feeling, attentiveness to the other's words, a belief in the reality of the other's world - of these and other elements are such conversations made, and at the same time the words themselves can be concerned with the simplest, most ordinary things:
"Look at that rock. "

― Kim Stanley Robinson , The Martians (Mars Trilogy, #3.5)