The novel “The Brains of Earth”, also published as “Nopalgarth”, by Jack Vance was published for the first time in 1966.
Paul Burke’s life changes when he receives an envelope containing a metal disk that floats in the air. When he receives a phone call from the sender, he ends up involved in an interstellar affair with an encounter with an alien named Pttdu Apiptix. L’alieno transports him to the planet Ixax to obtain his help to end a war that devastated his planet for a century.
Pttdu Apiptix explains to Paul Burke that the terrible war ravaged Ixax after the discovery that the inhabitants were infested with psychic parasites they called Nopals and that they also infest humans. To detach the Nopals from someone it’s necessary to use a machine that causes excruciating pain and the treatment must be repeated every month to prevent the parasite from re-attaching. Burke must find a way to subject humans to the same treatment or they will be exterminated.
The idea of invisible parasites that can affect humans had already been exploited, but Jack Vance develops it in his own way, adding another alien species that’s infested like humans and some typical elements of his works. The beginning is set on the planet Ixax, devastated by a war between the population without the Nopal parasite and the one influenced by the Nopals. The part set on Ixax is short, but Vance still offers one of his memorable descriptions which clearly gives the idea of the devastation that took place on the planet.
The presence of two sentient species infested by the Nopals allows Jack Vance to create a story that goes from the very beginning beyond the simple search for a way to eliminate the parasites. The Xaxan, the inhabitants of Ixax, already have a machine that allows them to detach a Nopal from one of them or a human, but basically, they have to subject them to torture. For Paul Burke, the problem is not only putting other humans in a condition where they can see the Nopals but also to subject them to a painful treatment. The long and hard war made the Xaxan very tough, so they have no qualms about it and Burke’s objections are dismissed with threats to exterminate humans.
The strength of “The Brains of Earth” lies precisely in the fact that the tension comes not only from certain horror tones of the story but also from multiple dangers for Paul Burke. The protagonist is motivated from the start after being put in a condition to see the Nopals and must find a way to save the humans from both Nopals and Xaxan. He wants to do some serious scientific research on the Nopals to find a way to painlessly detach them from their hosts, but he received what seems an impossible ultimatum.
The novel is short even by the standards of the time, so events have a pace with various twists. There’s not much room left for character development, also because the story follows Paul Burke while the others come and go. After his return from Ixax, there’s also a situation in which a normal characterization isn’t possible because the humans he meets react to his presence in an anomalous way.
Today “The Brains of Earth” would be classified as a novella. For this reason, in some editions, it was published together with other short novels by Jack Vance. Classification discussions aside, it’s not among Jack Vance’s masterpieces but has the merit of going beyond the paranoia that marked many stories written at the time of the Cold War with humans influenced by parasites. For this reason, I think it’s worth reading.