What do you think Faber means when he says, "those who don't build must burn"? Do you agree with him?
In this section of Farenheit 451, Montag asks for Faber's help in obtaining a reprint of his Bible, hoping that he will be able to return a copy to the authorities as needed to protect himself. Faber believes that books are critical in that they afford people the right to learn and to make up their own minds.
This quote, thus, highlights the extremes that have been created by the government's authority over the public's intellectual lives. Those who don't actively resist the government's influence might as well be burning books right along with them; there is no room for middle ground, inaction, and apathy at this time.
I agree with this quote and think that it especially applies to our current political climate. As we approach the upcoming 2016 presidential election, we are facing a huge turning point in the future of our country. Those who choose not to vote in this election are essentially choosing to "burn"; their apathy could lead to very serious consequences for Americans and the world alike.
What Faber is saying is similar to an old saying from the '60s -- "If you're not part of the solution, you're part of the problem." What he is saying is that people who do not want to do things that are helpful (building) are going to do things that are destructive (burning).
I do not really agree with this statement. I think that it is possible to be pretty neutral. I think that there are surely plenty of people who do not actively do especially good things. I count myself among them. I am not some big philanthropist or volunteer or anything like that. But, at the same time, I don't think I'm tearing anything down. I don't think that you have to be either a great benefit to society or a great harm. I think you can be neutral.