What does Montag think about the old women and all the books he has destroyed?

Beatty explains the irony behind their job. Everything is in fact fireproof. Their job was to put out the fires of discontent. Books contained ideas that challenged the government's pleasure principle. As long as people remained in a vacuous stupor of "contentment", they could forever remain in power. The word "intellectual" became dangerous. People who read books and thought for themselves formed ideas against the party and ideas are bulletproof (*I took that last line from a movie I like!) Firemen became the "guardians of people's comfort". They would destroy books before they could be manifested in people’s brains to form ideas; they are ideas which could threaten the delicate balance between happiness and ignorance, equality and inequality, which the government has tries so hard to achieve.

Oops I put this first response in the wrong category. My apologies. I'll respond to this one so people don't get confused.

Montag feels horrible for the old woman yet at the same time he envies her. Here is a human being standing up for what is right and true. He, on the other hand hides behind his title and uniform. The old woman changes Montag. He liberates (steals) books from her house and stashes them to read later. Although he is upset about the terrible sin he has committed, he is actually rebelling in his own way.