This quote is from Professor Faber, when he is explaining his history and his opinions on the structure of the future society. He knows that the public addiction to television is not accidental, but a deliberate construct of the government; it is the best way to propagandize and force the individual to believe what the government wants them to believe:
"My wife says books aren't 'real.'"
"Thank God for that. You can shut them, say, 'Hold on a moment.' You play God to it. But who has ever torn himself from the claw that encloses you when you drop a seed in a TV parlour? It grows you any shape it wishes! It is an environment as real as the world. It becomes and is the truth."
(Bradbury, Fahrenheit 451, Google Books)
With this quote, Faber shows how the TV screens have replaced critical thinking and rational reasoning; the people watching the screens no longer need to think about their lives, but instead they can be told what they are thinking and feeling. Since the entertainment is all emotional with no intellectual content, their feelings and emotions can be controlled, and they lack the abstract knowledge necessary to analyze those feelings. Books are concrete and solid; they are consumed at the pace of the reader. TV is linear; it moves at a specific pace and the watcher has no control over the content, or lack of content. Consumption of television is absorption of the creator's views and ideals; the viewer must accept those ideals to enjoy the show.