451 degrees fahrenheit is the temperature at which books burn. Old scientists thought spirits escaped from fire; furthermore, fire was considered an inflammable principle.
Q: What is the importance and possible significance of these two facts as they relate to Fahrenheit 451?
Bradbury's essential plea for personal and direct experience of ideas and feelings rather than synthetic entertainment suggests that in books there is a spiritual realm. And, it may be that when the paper and cardboard of a book are consumed in fire, that fire exudes this spirit of the emotion and human thought embedded in the pages.
Certainly, after Montag has talked with Christine in his neighborhood, something in his spirit has been awakened. After his encounter with her, Montag enters his home and reflects,
How rarely did other people's faces take of you and throw back to you your expression, your own innermost trembling thought?....He wore his happiness like a mask and the girl had run off across the lawn with the mask and there was no way of going to her door and ask for it back.
Once he has been stripped of his "mask," Montag becomes vulnerable, but also sensitive to the strong connection that people feel to their books, so strong that they are willing to die rather than live without them. For, books give meaning to life. As he speaks to Professor Faber in the park, Montag begins to comprehend the spiritual significance of books:
"I don't talk things, sir," said Faber. "I talk the meaning of things. I sit here and know I'm alive."
The "meaning of things" cannot be destroyed by burning; this existential quality escapes through the flames and becomes part of the universe to be later imbued in the thoughts of another writer.