After he has floated a while, his heels scrap on the pebbles of shore. He sees the land as a menacing creature.

"He looked in at the great black creature without eyes or light, without shape, with only a size that went thousands of miles, without wanting to stop, with its grass hills and forests that were waiting for him." (pg 141)

When he steps from the river, he is overcome with fear.  The land is causing the fear.  It brings back memories of a fearful childhood incident.

"The land rushed at him, a tidal wave.  He was crushed by darkness and the look of the country and the million odors on the wind that iced his body.  He fell back under the breaking curve of darkness and sound and smell.  He whirled......He wanted to plunge in the river again and let it idle him safely on down somewhere.  This dark land rising was like that day in his childhood, swimming, when from nowhere the largest wave in the history of remembering slammed him down in salt mud and green darkness, water burning mouth and nose, retching his stomach, screaming!  Too much water!

Too much land." (pg143)

He sees two eyes in the darkness, and he thought it was the Hound.  He gave a last loud shout, and the eyes exploded and were gone.  It was a deer.  He then started walking and was filled with all the scents of the earth.  Suddenly his fear diminished.

"He stood breathing, and the more he breathed the land in, the more he was filled up with all the details of the land.  He was not empty. There was more than enough here to fill him.  There would always be more than enough." (pg144)

However, his greatest comfort comes when he finds something manmade; railroad tracks.

"Here was the path to wherever he was going.  Here was the single familiar thing, the magic charm he might need a little while, to touch, to feel beneath his feet as he moved on into the bramble bushes and the lake of smelling and feeling and touching, among the whispers and the blowing down of leaves." (pg 145)

It was the fear of the unknown, of what those forest and hills could offer him. He was unfamiliar with the land and he had no idea how to survive.  He was terrified.

One example of man's desire to survive is demonstrated by Montag's wife.  She is frightened by the fact that he is bringing books into their home and this puts them in danger. She does what she feels she needs to to to survive and turns him in.  As they are about to burn the house, she gets into a car and leaves him standing there looking after her.

Another obvious example of Montag's desire to survive is when he kills Beatty and runs to Faber for help.  He disguises his scent and runs toward the river to escape capture and death. 

Most of the people in the community have adapted to the laws in order to survive.  They don't question the law about no books because they realize if they do their lives are at risk. 

In many ways the whole story is about man's will to live.  The question becomes what would man trade for his survival.  Some ran away to the woods, some conformed to the law, but in their own way each was fighting for survival.

This is an interesting question because the majority of the conflicts are person vs. person or person vs. technology. One way to think about this is to consider Montag's human nature. He has been taught to suppress any "natural" curiosity about literature or critical thinking. Indeed, he is born with the ability to be curious and with the ability to read and think critically. But Beatty and other people in power have brainwashed him to suppress these abilities. So, in a sense, Montag is fighting against his own nature. Upon talking to Clarisse and Faber, he fights through this brainwashing and eventually gives in to his natural curiosity about literature and human thinking. In this case, thankfully, nature wins.

For a more traditional notion of person vs. nature, consider Montag's race to freedom at the end of the book. He runs through people's yards in order to get to the river. He has to risk swimming through the river in order to escape the Mechanical Hound. He does float peacefully down the river, happy to be away from his old life. But when he reaches land, he is overwhelmed with what he has been through and with the journey that awaits him:

He wanted to plunge in the river again and let it idle him safely on down somewhere. This dark land rising was like that day in his childhood, swimming, when from nowhere the largest wave in the history of remembering slammed him down in salt mud and green darkness, water burning mouth and nose, retching his stomach, screaming! Too much water! Too much land!

After all the running and rushing and sweating it out and half-drowning, to come this far, work this hard, and think yourself safe and sigh with relief and come out on the land at last only to find . . . The Hound!

It turns out to be a deer. But these passages shows how Montag does have to struggle against nature during his mad dash to freedom.

In "Fahrenheit 451" there are many examples of the more negative aspects of man's nature-their laziness, violence, apathy, and passivity.  All of Clarisse's friends are ultra-violent, killing each other constantly, enjoying violent games, and driving fast.  They also don't talk to each other or make any lasting relationships; it's much easier to stay dissociated.  Mildred's friends are examples of passivity and apathy.  The war takes their husbands away and they deny being upset about it; they passively go about their lives, believing the government who tells them it'll only be a couple weeks.  When confronted with active thinking or emotion, they break down.  Mildred, miserable, tries to kill herself but is apathetic about creating any real change in her life that would help her to be happy.  The people are too lazy to read, to form relationships, to change their circumstances or to challenge authority.

As for man's more positive innate traits, like striving for betterment, for enlightenment, and for meaning in life, Montag, Clarisse and Faber can be seen as examples of people who strive for those more noble traits. Unfortunately, they live in a society that drowns those traits out with busyness, pleasure, and a stifling government.  In the end though, hopefully Montag can help to change that, and to rebuild a place where man's more positive traits can thrive.