The response of the "police car"--the one and only police car since the election of 2052--was a simple and rather disparaging one. In this futuristic Bradbury short story, Mead is out walking at night in "sneakers" so as not to have an audible footstep since the security dogs "paralleled" his walk if they heard footsteps: they needed something to do as in ten years of walking Mead had never encountered another person out walking, "not one."
When he is within one block of returning home, the one and only police car, which was automated, suddenly rounds a corner and, after blinding him with bright white light, shouts that he stay where he is and stand still "Or we'll shoot!"
It is in this surprising context that the automaton police car asks Mead his "Business or profession?" Mead answers that he may be considered a writer although, we learn later, he hasn't written anything for ten years. The police car prophetically replies: "No profession." The police car makes this response because "Magazines and books" no longer sell because everyone (as in Fahrenheit 451) stays in and watches television with the "gray or multicolored lights touching their faces."
"Your name?" said the police car is a metallic whisper. ...
"Leonard Mead." he said.
"Business or profession?"
"I guess You'd call me a writer."
"No profession," said the police car, as if talking to himself. ...
"You might say that," said Mr. Mead.