Men have gathered in front of the United Cigar Store in town and are discussing all of the bad things happening in the world. Leo Auffmann, the jeweler, wants them to stop being so glum, and Grandfather Spaulding, walking by with Douglas and Tom, points out to him that to stop such talk he should invent something to make the world better. Douglas adds that Leo should make a happiness machine, and although they were joking, he takes them seriously and sets off on his bicycle to go home and start working.
As Leo Auffmann pedals home we learn that he is a man who thinks about everything, and he decides that his Happiness Machine must help people deal with the changes in life that are difficult—growing up, getting old, and dying. When he gets home he is greeted by his six children, Saul, Marshall, Joseph, Rebecca, Ruth, and Naomi, and learns that they have ice cream to eat with him. Savoring the ice cream with his family, Leo asks his wife Lena what she would think if he attempted to make a Happiness Machine. She answers with a question of her own: "Something's wrong?"
As Grandfather walks Douglas and Tom home, Charlie Woodman, John Huff and a group of the boys run by, and Douglas dashes off with them. Later that night, after Tom and Mother eat the ice cream that Tom got at Mrs. Singer's store, his mother calls Douglas's name to get him to come back home. Tom realizes that his mother is nervous and that she is angry with Douglas for being out so late. Father is out at a lodge meeting and will not be back until late. Tom and his mother go for a walk, looking for Douglas, and she mentions that the Lonely One is around and that it is not safe to be out. When they get to the ravine, Tom senses that his mother is afraid, and he cannot understand that, because she is an adult. He realizes "that each person was to himself alone," and that there would be no help for him there. The growing sense of danger and fear mounts until finally Tom is relieved to hear Doug's voice in the distance. His mother promises Douglas that he will get a spanking and shows no signs of the fear that had wracked her moments before, but Tom knows the fear is there and is glad that night that Douglas is in bed next to him.
Late that night Leo Auffmann brainstorms ideas for the Happiness Machine on his front porch. Lena comes out and mentions to him that they do not need the machine. Leo agrees but tells her that sometimes you must build things for others. Lena's silence demonstrates where she stands, but Leo continues to dream of the features of the machine that could bring happiness to people. A moment later the porch is empty and the night is over.
Leo Auffmann takes seriously the challenge to invent a Happiness Machine, and this is an attempt that from the beginning can only end in failure. He is a brilliant inventor, but happiness is not in the realm of inventions. His wife's question shows that she understands that there is no need to build such a thing, but he insists that it would help others. The pure happiness of Leo's life is contrasted with his difficult search to create a machine to generate happiness. Metaphorically, the machine represents the attempt to control our emotions—to ensure that things are always good. However, this is impossible. It is impossible in a general sense because people simply are not always happy, and happiness would lose its meaning if there were no other alternative.
The impossibility of the Happiness Machine is beautifully elucidated by the fear that Tom and his mother feel. The ravine, and the nature beyond it, represents the unknown. There will always be fear of the unknown, because it cannot be predicted and it cannot be controlled. Leo's Happiness Machine could never overcome that fear. It could never take into account the unknown fears that cloud people's hearts. Tom's sense of fear comes mostly from his mother's, because he believes at first that he is safe with her since she is an adult. When he understands that she is afraid he tries to understand why, and he realizes that out there at the ravine there is no way for anyone to help them. They are utterly alone, and, beyond that, he and his mother must deal with their demons on their own. What Tom comes to understand is that, ultimately, we have only ourselves to rely on—the institutions of society and civilization cease to hold any personal meaning at the ravine, where the natural world takes over.
Moreover, our fears are not necessarily shared. The Lonely One worries his mother, but with his friends Douglas is carefree. Douglas was happy while his brother and mother were very scared, and this points to the fact that happiness, like other human emotions, is relative. It is not quantifiable and cannot be strictly defined, and so any attempt to build a Happiness Machine would fail by definition. It would be an attempt to construct something that has different meanings to different people. The example of Douglas happily running through the wilderness with his friends while his family worries about him is only one of millions of such examples. In fact, it makes sense that most of the time that people are worried about someone that person themselves does not share the worry—otherwise they probably would not partake in the action.