What does Montag imagine Beatty would say about the content of books in Fahrenheit 451?

Montag does not have to imagine very hard to know what Beatty would say about the content of books.  In the first part of the book, when Montag is home from work one day, Beatty uses the ruse that he is simply visiting Montag, but his real purpose there is to explain to Montag why their society is the way it is and why it's good.  Among other things, he tells Montag that books made people unhappy because they offended some people, or because they made people compare their own dull lives to the exciting lives of book characters, or because they simply made people think and realize the shortcomings of themselves and their world.  Beatty believed that books allowed and helped people to think.  Later, in part two of the story, right before the fire run is made to Montag's house, Beatty tries to get Montag to see how books' authors contradict one another and confuse people with the contradictions.  Again, Beatty believed books helped people to think and that was something the society of the book did not want.  The ruling power especially did not want that to happen because thinking people are harder to control.  Whether or not Beatty completely believed this is not clear.  Beatty was obviously a well-read man.  He had to be to know as much about and from books as he did.  After Montag killed Beatty, Montag realizes that Beatty had wanted to die.  Beatty purposely badgered Montag while Montag held the flame thrower.