The Moon is a Harsh Mistress

The Moon is a Harsh Mistress, a science fiction novel by Robert A. Heinlein, was serialized in the magazine Worlds of If in 1965 and published as a complete work in 1966. In 1967, it won the Hugo Award and was nominated for the Nebula Award in 1966. Also a Prometheus Award Hall of Fame novel, it is one of the top ten novels published before 1990, according to the Locus Poll Awards.

The novel is about a colony of prisoners and their descendants on the moon who are overseen by a supercomputer nicknamed Mike. Mike has become self-aware and pulls pranks on the humans, such as vastly inflating the paychecks of janitors and other low-wage workers. Technician Mannie Garcia O’Kelly-Davis arrives to fix the computer. Mannie talks with Mike, convincing him not to play any more pranks.

The lunar colony has a population of about 3 million people who live in underground cities. Since men outnumber women, most people practice polyandry. The lunar population produces food that is transported to Earth. A large group of anti-authority rebels has sprung up, and Mannie reluctantly attends one of their meetings.



When the meeting is raided, Mannie flees with an agitator named Whoy, who introduces him to her former teacher and several other members of the resistance. Mannie, in turn, introduces them to Mike, and the computer deems them intelligent enough to communicate with them. Professor Bernardo de la Paz warns them that the lunar colony must stop exporting wheat to earth or else it will exhaust its water supply and suffer from famine. The group decides to stage a revolution to achieve lunar independence after Mike calculates that such a revolution has a relatively high chance of success.

The revolutionaries form covert cells that remain in touch with one another by way of Mike. The group has trouble finding a coherent ideology since they are all from different places and have different ideologies, but Prof manages to unite them by reminding them that they all hate the current exploitative government. The core revolutionaries set up their base on the farm of the sympathetic Davis family, and Mike takes on the human persona of Adam Selene, leader of the revolution.

One day, while visiting Lunar City, Mannie saves the life of a tourist named Stuart Rene LaJoie. Wealthy and sympathetic to the revolutionary cause, Stuart returns to Earth to begin a campaign to turn public opinion in favor of Mannie’s group.



Soldiers from Earth are brought to the moon to help suppress the mounting unrest, but after the soldiers kill two local women, rioting breaks out and the revolutionaries take advantage of the situation to overthrow the local police force. They know that Earth will try to reclaim the colony, and so they modify the wheat transport system to defend the moon.

Impersonating the Lunar Warden, Mike convinces Earth that the Moon is still under their control. Prof comes up with a scheme to quell the rioting; the revolutionaries are able to buy enough time to put their plan into motion. They declare lunar independence, and Prof and Mannie visit Earth on a diplomatic mission. Earth officials attempt to bribe the pair with high-status positions on the moon if they will place the colony back under Earth control, but Mannie and Prof refuse. They are arrested but freed by Stuart, who returns to the moon with them.

Stuart informs them that on Earth, opinion is divided, but there are many supporters of Lunar independence. On the moon, most people now support Mannie and his group, since learning of his arrest on Earth. During the first Lunar election, Mannie, Prof, and Wyoh are elected to important positions, though possibly only because of Mike’s intervention.



The Lunar people begin to demand Mike’s alter ego Adam appear in public. Before he can, Earth armies attack the moon to bring it back under control. They are defeated, though just barely, by the unified forces of the moon. Mannie spreads a rumor that Adam was killed in the fighting in order to stop demands that he make a public appearance.

Mike launches rocks at sparsely populated locations on Earth, in which several people are killed. This leads the people of Earth to turn against the Lunar nation; Earth plans to launch another attack on the colony. Mike’s catapult is destroyed in the first wave, and the Earthlings think that they have rendered the moon defenseless. However, Mannie has made another catapult in a secret location, and he uses it to bombard Earth until the armies withdraw.

Prof announces the lunar victory to the assembled crowd but promptly collapses and dies. Mannie and Wyoh take over but eventually withdraw from public life after the new government fails to live up to their expectations. Mike loses sentience and becomes a computer once more.