A World of Difference  
Cover of the 2005 edition
Author Harry Turtledove
Cover artist Cliff Nielsen
Language English
Genre(s) Science fiction, Alternate History
Publisher Del Rey
Publication date 1990

A World of Difference (Del Rey, 1990) is a science fiction novel by Harry Turtledove. The book begins with a space voyage that departed Earth in an alternate 1989.[1]

In this timeline, the planet we know as Mars does not exist. In its stead is the planet Minerva, which is larger and closer to the Sun, allowing it to have a breathable atmosphere and extensive ecology including an intelligent species. Minervan Fauna (including the sentient Minervans) are radially symmetrical, which means that they have eyes spaced all around their bodies, can see in all directions at once and have no "back".

Females, called mates, almost invariably become pregnant at puberty, give birth to litters - one male, five female - and always bleed to death immediately afterwards; the idea of an old female is considered an oxymoron. This makes females considered expendable and traded as property, although the novel is inconsistent on this last point.

The Minervans live in a neolithic feudalist society; some societies show signs of early mercantile capitalism - which, like similar societies in Earth's history, is accompanied by predatory expansionism. Since temperatures never reach the melting point, ice is considered a stable building material and substantial structures are made of it.

The ancient astronomers of this timeline named the bright blue/gray planet Minerva after the goddess of wisdom. However, other than having a planet named for a different deity of the Classical Roman pantheon, human history on Earth is much the same as in OTL until the second half of the 20th century.

When the Viking 1 space probe lands on Minerva in 1976, it takes a picture of a native Minervan wielding a primitive tool; proving the existence of intelligent life on other worlds. This makes Minerva far more interesting than OTL Mars, to both the US and the Soviet Union, and both consider Minerva worthy of spending the money and effort of sending a manned expedition. The two superpowers embark on a race, each trying to reach Minerva first. This has the result of perpetuating the Cold War, with Mikhail Gorbachev's Glasnost reforms being swiftly aborted and Gorbachev himself retains power for only nine months before dying from a stroke (though there are rumors of a secret assassination). In the 1990s the Soviet Union is still very much around, and the security services maintain a tight control over daily life.

The main action of the story involves separate American and Soviet missions, who both pay lip service to non-interference with Minervan society, but in the course of their research, the teams' respective political ideologies inevitably come to the fore. This leads the teams and their commanders back home to use the Minervans in a transparent analogy to Third World Cold War proxy conflicts on Earth.

Eventually, Minervans get their hands on high tech items like steel hatchets, rubber rafts, and finally AK-74s, which severely disrupt their way of life. But of potential far more fundamental significance, human women - finding intolerable the situation of female Minervans in general, and having come to very much like one specific female - find a way of saving her life and letting her survive childbirth. If repeated on a larger scale, this has the potential of radically changing the basic patterns of Minervan social life.


  1. On page 24, it is stated that Leonid Brezhnev was "seven years dead". The novel gives no reason to think that Brezhnev died in a different year than in OTL.