The then sat back. "You're confused now. You have a lot of information you don't know how to use yet. It was given to you fast, and your mind hasn't absorbed it and put it in order. Sometimes it helps if you talk out your problems."  
"I don't know if I have a problem." The man brushed his hand slowly across his eyes. "Where do I start?"
 
"Let me do it for you," suggested Borgenese. "You ask questions when you feel like it. It may help you."
 
He paused, "You were found two weeks ago in the Shelters. You know what those are?"
 
The man nodded, and Borgenese went on: "Shelter and food for anyone who wants or needs it. Nothing fancy, of course, but no one has to ask or apply; he just walks in and there's a place to sleep and periodically food is provided. It's a favorite place to put people who've been retroed."
 
The man looked up. "Retroed?"
 
"Slang," said Borgenese. "The retrogression gun ionizes animal tissue, nerve cells particularly. Aim it at a man's legs and the nerves in that area are drained of energy and his muscles won't hold him up. He falls down.
 
"Aim it at his head and give him the smallest charge the gun is to, and his most recent knowledge is subtracted from his memory. Give him the full charge, and he is swept back to a childish or infantile age level. The exact age he reaches is dependent on his physical and mental condition at the time he's retroed.
 
"Theoretically it's possible to kill with the retrogression gun. The person can be taken back to a stage where there's not enough nervous organization to sustain the life process.
 
"However, life is . As the lower levels are reached, it takes increasing energy to subtract from anything that's left. Most people who want to get rid of someone are satisfied to leave the victim somewhere between the mental ages of one and four. For practical purposes, the man they knew is dead—or retroed, as they say."
 
"Then that's what they did to me," said the man. "They retroed me and left me in the Shelter. How long was I there?"