The bloodstream in this woman was new and it seemed to have done a new thing to her. Her cheeks were very pink and her lips were very fresh and full of color and they looked soft and relaxed. Someone else’s blood there. If only someone else’s flesh and brain and memory.

After Mildred overdoses on sleeping pills and has her blood replaced, Montag notices how full of life she suddenly looks as opposed to how she looked before. However, he knows that this vivacious appearance is only on the surface and will soon disappear. Mildred’s shallowness and emptiness will eventually poison the fresh blood one way or another. Here, blood symbolizes a person’s true inner self; Mildred has been given a fresh start with new blood, but as she is empty, the benefits of the new blood will quickly fade.

He and the white plaster walls inside were much the same. There was white in the flesh of his mouth and his cheeks and his hair was white and his eyes had faded, with white in the vague blueness there. Then his eyes touched on the book under Montag’s arm and he did not look so old any more and not quite as fragile. Slowly, his fear went.

When Montag first sees Faber at his house, he notices how pale the professor is. However, once Faber sees the book that Montag has brought with him, some life comes back into his face. The way Montag sees it, blood is a symbol for life and vitality, and Faber’s thirst for knowledge is what brings the blood back to his face and brain. Such a detail implies that knowledge and what we can learn from books are essential to being fully alive.

The faces of those enameled creatures meant nothing to him, though he talked to them and stood in that church for a long time, trying to be of that religion, trying to know what that religion was, trying to get enough of the raw incense and special dust of the place into his lungs and thus into his blood to feel touched and concerned by the meaning of the colorful men and women with the porcelain eyes and the blood-ruby lips.

As Montag looks at the faces of women on the parlor walls, he is reminded of looking at statues in a church and wanting to understand their significance. To Montag, in order to fully appreciate and understand something, it needs to be real enough that he can practically feel that he is inhaling it into his bloodstream, symbolizing his desire to learn and absorb all he can. The parlor walls are a sort of religious place to Mildred and the people on them are like the empty statues he once tried and failed to understand. This moment reveals how different Montag is from those around him; he wants to feel real and alive rather than like he is merely acting in or sleepwalking through a fantasy.

The river was very real; it held him comfortably and gave him the time at last, the leisure, to consider this month, this year, and a lifetime of years. He listened to his heart slow. His thoughts stopped rushing with his blood.

Once Montag escapes the Mechanical Hound and is safely in the river, he is finally able to slow down and take in the nature around him, perhaps for the first time ever. Here, both Montag’s blood flow and thoughts slow down. Such a connection shows that his blood flow symbolizes his inner state of mind. Once he is able to be on his own in nature, away from technology and other people, he finally experiences some peace and is able to reflect upon his own thoughts and past experiences.

Look at the world out there, my God, my God, look at it out there, outside me, out there beyond my face and the only way to really touch it is to put it where it’s finally me, where it’s in the blood, where it pumps around a thousand times ten thousand a day.

After the city is destroyed, Montag considers where he and the group will go next, and he imagines how much there is to see and know in the world. Here, Montag’s thoughts reveal that seeing and learning things aren’t enough: He wants to ingest them, to merge with them, to make these new experiences and places a part of him, circulating in his bloodstream. Unlike Mildred, who was full of easily replaceable blood that she could only poison from the inside, Montag wishes his blood—his inner self—to be purified and strengthened by the outside world.