Chapter thirteen continues “The Happiness Machine” theme. Leo, still infatuated with building the Happiness Machine, asks Lena if she is “pleased, contented, joyful, or delighted.” Lena gives a mocking reply which offends Leo who is taking his goal seriously, and they get into an argument. The quarrel ends only when Lena realizes that she’s burned their dinner for the first time in twenty years.
Leo then spends several weeks laboring in his garage to build his Happiness Machine. During this time, the state of his family falls to pieces, but Leo is too busy with his invention to pay attention to his wife’s forewarning.
At last, Leo completes his Happiness Machine. As luck would have it, the Happiness Machine turns out to cause sadness instead of the anticipated happiness, causing both Saul, his son, and Lena to weep after sitting in it. Lena explains to him that a Happiness Machine cannot be built for humans because it would only give them everything they wanted all the time, and produce no fulfillment. Besides, it makes them pine for things they shouldn’t even be thinking about, such as when a dancing stimulation in the Machine caused her to miss the times when Leo would take her out for dances, hence causing them to feel only unhappiness about their lives. Leo, still disbelieving, decides to take a test run in the Machine himself, but just as he is about to do so, the Machine catches fire, and burns down to the ground.
After the incident, Leo comments to Douglas and his father that he’s been a fool because the real Happiness Machine has been right in front of him all along. He shows them his newfound Happiness Machine running in perfect order — his family.