When does the narrator mention Plato in the novel Fahrenheit 451?

At the beginning of Part II, Montag calls Faber and asks him how many copies of the Bible are left in the country. Faber is startled at the question and responds by saying that he doesn't know. Then, Montag asks Faber, "How many copies of Shakespeare and Plato?" (Bradbury 72). Faber angrily responds by saying that there are no copies of either books. Although Montag does not directly state whether or not he has any editions of Shakespeare or Plato, it is implied that he possesses those rare books. Montag is curious as to how rare the books are that he possesses which is why he calls Faber. Plato's Republic is a famous work of literature that discusses both philosophy and politics. The Republic has drastically influenced philosophical thought throughout history and would be considered detrimental to society in Fahrenheit 451. Plato's ideas of government drastically contrast with the authoritative regime in Bradbury's dystopian novel.