Thoreau’s good friend William Ellery Channing sometimes accompanied him on his fishing trips when Channing came out to Walden Pond from Concord. Thoreau creates a simplified version of one of their conversations, featuring a hermit (himself) and a poet (Channing). The poet is absorbed in the clouds in the sky, while the hermit is occupied with the more practical task of getting fish for dinner; at the end the poet regrets his failure to catch fish.

Thoreau plays with the mice that share his house, describing one that takes a bit of cheese from Thoreau’s fingers. He also has regular encounters with a phoebe, a robin, and a partridge and her brood; he calls these wild birds his hens and chickens. Less frequently he sees otters and raccoons. Thoreau is struck by the raccoons’ ability to live hidden in the woods while nevertheless sustaining themselves on the refuse of human neighborhoods. About a half-mile from his habitation, Thoreau digs a makeshift well to which he often goes after his morning’s work to eat his lunch, gather fresh water, and read for a while. There he frequently encounters woodcocks and turtledoves.

On one occasion, Thoreau happens to notice a large black ant battling with a smaller red ant. Examining the scene more closely, he sees that it is actually part of a large conflict pitting an army of black ants against an army of red ants twice its number, but whose soldiers are half the size of the black army. Thoreau meditates on its resemblance to human wars, and concludes that the ants are just as fierce and spirited as human soldiers. Thoreau removes a wood chip, along with three ant combatants, from the scene of the battle, carrying it back to his cabin to observe it. He places them under a turned-over glass and brings a microscope to watch their struggle. After witnessing a pair of decapitations and some cannibalism, he releases the survivor.

Thoreau frequently encounters cats in the woods. Although domesticated, they prove quite comfortable in the woods, so inherently wild as to spit at Thoreau when he comes too closely upon them. Thoreau remembers one cat that was said to have had wings, perhaps resulting from crossbreeding with a flying squirrel. Although he never sees this cat, he was given a pair of her “wings” (pieces of matted fur that she shed in the springtime), and says that as a poet, he fancies owning a winged cat. Out on the pond in his boat, Thoreau at times pursues the loon, hoping to get close enough for a long look. In general, the loon allows him to advance to only a modest distance before diving deep into the water, surfacing again with a loud laugh. Thoreau sees no rhyme or reason in this ritual, or in the movements of the ducks, or in any of the motions that his other “brute neighbors” go through. He concludes that they must be as enthralled by the water and its natural surroundings as he is.

Combing the meadows for wild apples and chestnuts, Thoreau is dismayed by how nature’s bounty has been plundered for commercial use. Still, there is enough left for him to feast on. The changing leaves of autumn provide a brilliant spectacle, though Thoreau is well aware that they herald the coming hardships of winter. Wasps flee the colder weather in thousands, and Thoreau is forced to retreat to his quarters. He goes to another side of the pond for a while to soak in the remaining rays of the fall sun, which he prefers to “artificial” fire. Toward the end of summer, Thoreau studies masonry to build a chimney for his cabin with the help of his friend Channing. By November, Thoreau’s summer labors have proven a good investment, as the fires keep him warm at night.

Walden Pond has begun to freeze over in places, allowing Thoreau to walk on the thin surface and glimpse the deep waters beneath. Fascinating as the underwater activity is, the ice itself equally captivates Thoreau, especially the air bubbles that rise to the surface and wriggle themselves into the ice. Breaking off portions of the ice to examine them and observing the same spots day after day, Thoreau learns how ice forms around the bubbles. He understands how the bubbles make the ice “crack and whoop.” With winter fully upon him, Thoreau settles into a winter routine, gathering wood for his fires, and listening to the geese as they migrate south. The gathering of firewood becomes an essential occupation. Thoreau uses various types of wood and brush to kindle his fires, preferring pine but often settling for dry leaves. Warming himself and cooking his food, snugly ensconced with the moles that nest in his cellar, Thoreau reflects that fire warms the poor and the privileged alike, and that every man would die if another ice age occurred.

At first glance Thoreau’s allegorical dialogue between the hermit and the poet seems fanciful, not very profound, and not well integrated with the animal theme of the chapter. But in fact it reveals much about Thoreau’s self-image, and about how he sees his own project not as that of a dreamy artist, but of someone who lives life to its fullest—like the animals before him. The poet in the dialogue offers his silly impressions about how the clouds hang in the sky, and how he has seen nothing like it in old paintings or foreign lands, not even on the coast of Spain. By contrast, the hermit Thoreau’s thoughts tend toward more practical concerns like the tubs that need to be scoured, the boiled beef to be eaten, and the fact that his “brown bread will soon be gone.” Food is a prominent presence in his meditations, and there is a deep significance in the poet’s final complaint that he has not caught enough fish, having used worms that are too large. Thoreau may be hinting that, instead of rhapsodizing about Spain and old pictures, the dreamy poet should have been paying attention to practical matters like the proper bait for fishing. He implies that life is not a poem but a matter of food gathering and survival, and the high-flying artist who ignores this fact will suffer later.

This odd dialogue thus provides a preface to the chapter on animals, “Brute Neighbors,” in ironically suggesting that humans and animals are indeed neighbors, and we are all “brutes” seeking food, shelter, and survival. The various vignettes of animal life offered in this chapter focus on animals involved in practical matters of survival, especially in the search for food. The mouse that Thoreau shares his house with is tame and entertaining, but the end point of the entertainment is the acquisition of the bit of cheese. Just like the fishing conversation between the poet and hermit, this interaction between human and mouse is based on food, and it is over when the cheese is gobbled up. The raccoon too is no more truly wild than this half-tamed, home-dwelling mouse. It is not a wild denizen of the forest, but a frequenter of neighborhoods in search of food from human sources. As with the mouse, the animal and human neighbors coexist on the basis of their shared food supplies, which makes feeding the common denominator between them. Similarly, the wild cat that hisses at Thoreau on a walk in the woods was originally, he conjectures, no different from the domestic pet “which has lain on a rug all her days.” The housebound and the savage, like the human and the brute, are close counterparts.

The warring ants that Thoreau finds make the connection between humans and brutes no less clear: the distinction between human civilization and animal savagery breaks down when red ants are seen waging a very human war against the black ants. “For numbers and for carnage it was an Austerlitz or a Dresden,” says Thoreau, mentioning two famously bloody battles of the nineteenth century. He sees the human aspect of their war immediately. When he narrates the thrilling scene of the large black ant beheading several smaller red ones, we feel the importance of survival even more sharply than we do in the context of food supplies: all these ants are fighting for their lives. The analogy to the human will to survive is clear.

Emphasizing the survival instincts that humans and brutes share does not necessarily imply, for Thoreau, that life is a dead-set fixation on practical gains alone. Animal life, no less than human life, has its eccentricities and irrationalities as part of the package of existence—as Thoreau illustrates by concluding his animal survey with a famously silly creature, the loon. This bird is no less committed to survival than the partridge, the robin, or any of the other birds or beasts mentioned in this chapter. But the loon is also, quite openly, loony. His battle of wits with Thoreau on the pond, diving in a way that makes Thoreau miscalculate where he will reappear and then surfacing unexpectedly elsewhere, serves no practical purpose. He even leads Thoreau to a wider expanse of water where he can maneuver more freely, for no other reason than to increase his fun.

Yet even this game is not played too seriously; the loon puzzles Thoreau by trying hard to sneak up on him only to reveal its location at the last moment. The bird betrays itself because it can afford to do so, since at this moment its life and survival are not at stake. Survival may be the main focus of animal and human existence, but life is more than a struggle, and even nature has its moments of fun and frivolity—like the poet at the beginning. Perhaps the poet and the hermit are not so different, but are rather two aspects of nature and of the man Thoreau imagines himself to be. It is significant that when recounting the old wives’ tale about a winged cat, Thoreau says that this “would be the kind of cat for me to keep,” since a poet deserves a fantastic animal. This comment is revealing, since with it Thoreau directly acknowledges himself to be a poet, after mocking poets in the opening dialogue. What the chapter shows above all is that, for humans and brutes alike, survival and frivolity are both parts of life.