"What was that green spray when it hit you?"
"Explain greenspray."
By referring to wavelengths and describing airborne water droplets, with a side excursion into wave and wind action, McKie thought he conveyed an approximate idea of green spray.
"You observe this phenomenon?" the Caleban asked.
"I saw it, yes."
"Extraordinary!"
McKie hesitated, an odd thought filling his mind. Could we be as insubstantial to Calebans as they appear to us?
He asked.
"All creatures possess substance relative to their own quantum existence," the Caleban said.
"But do you see our substance when you look at us?"
"Basic difficulty. Your species repeats this question. Possess no certain answer."
"Try to explain. Start by telling me about the green spray."
"Greenspray unknown phenomenon."
"But what could it be?"
"Perhaps interplanar phenomenon, reaction to exhalation of my substance."
"Is there a limit of how much of your substance you can exhale?"
"Quantum relationship defines limitations of your plane. Movement exists between planar origins. Movement changes referential relatives."
No constant referents? McKie wondered. But there had to be! He explored this aspect with the Caleban, questions and answers obviously making less and less sense to both of them.
"But there must be some constant!" McKie exploded.
"Connectives possess aspect of this constant you seek," the Caleban said.
"What are connectives?"
"No . . ."
"Referents!" McKie stormed. "Then why use the term?"
"Term approximates. Tangential occlusion another term expression something similar."
"Tangential occlusion," McKie muttered. Then, "tangential occlusion?"
"Fellow Caleban offers this term after discussion of problem with Laclac sentient possessing rare insight."
"One of you talked this over with a Laclac, eh? Who was this Laclac?"
"Identity not conveyed, but occupation known and understandable."
"Oh? What was his occupation?"
"Dentist."
McKie exhaled a long, held breath, shook his head with bewilderment. "You understand - dentist?"
"All species requiring ingestion of energy sources must reduce such sources to convenient form."
"You mean they bite?" McKie asked.
"Explain bite."
"I thought you understood dentist!"
"Dentist - one who maintains system by which sentients shape energy for ingestion," the Caleban said.
"Tangential occlusion," McKie muttered. "Explain what you understand by occlusion."
"Proper matching of related parts in shaping system."
"We're getting nowhere," McKie growled.
"Every creature somewhere," the Caleban said.
"But where? Where are you, for example?"
"Planar relationships unexplainable."
"Let's try something else," McKie said. "I've heard you can read our writing."
"Reducing what you term writing to compatible connectives suggests time-constant communication," the Caleban said. "Not really certain, however, of time-constant or required connectives."
"Well . . . let's go at the verb to see, "McKie said. "Tell me what you understand by the action of seeing."
"To see - receive sensory awareness of external energy," the Caleban said.
McKie buried his face in his hands. He felt dispirited, his brain numbed by the Caleban's radiant bombardment. What would be the sensory organs? He knew such a question would only send them off on another empty label chase.
He might as well be listening to all this with his eyes or with some other organ rude and unfitted to its task. Too much depended on what he did. McKie's imagination sensed the stillness which would follow the death of this Caleban - an enormous solitude. A few infants left, perhaps - but doomed. All the good, the beautiful, the evil . . . everything sentient . . . all gone. Dumb creatures which had never gone through a jumpdoor would remain. And winds, colors, floral perfumes, birdsong - these would continue after the crystal shattering of sentiency.
But the dreams would be gone, lost in that season of death. There would be a special kind of silence: no more beautiful speech strewn with arrows of meaning.