The Left Hand of Darkness follows the path of Genly Ai, who comes to the planet of Gethen as an envoy from an intergalactic government. Throughout the story, the most important recurring character is Therem Harth rem ir Estraven, who proves to be the only person Genly meets who believes in his mission. Amongst all the treachery and paranoia of the other Gethenians, it was Estraven who ensured the future of his people by making sure Genly succeeded in his mission. By doing so, Estraven proved he was the most human of any of the Gethenians in the story.

The first place Estraven demonstrates his belief in Genly is in Karhide, when he is the prime minister for the mad king Argaven. Argaven’s madness drives him to constant paranoia, and he believes Estraven is trying to overpower him. For this, he is banished to Orgoreyn. When Genly travels to Orgoreyn for a more open-minded setting, it proves to be little better. The bureaucrats who rule the country don’t trust any among them, least of all Genly. In an inversion of the betrayal in Karhide, they imprison Genly and let Estraven, a known traitor in Karhide, walk free. In the first half of the book, Estraven demonstrates his faith in Genly. The ability to believe in something for which there is no proof is a human trait, and Gethenians largely do not exhibit it. Neither the king nor the governors of Orgoreyn believe Genly is what he says he is.

When Genly is imprisoned by the Orgota, Estraven’s true character makes itself known. He is safe in Orgoreyn, but surrounded by liars who do not believe in the big picture- joining the Ekumen and becoming part of humanity as a whole. They can only see as far as beating Karhide to the punch, and in their fear imprison their only chance of doing so. Despite the fact that Estraven knows Genly does not trust him, he still trusts Genly above anyone else, and goes to great lengths to rescue him from the camp. He knows that the only way to ensure Genly’s success is to risk his own life and take Genly back to Karhide over the Gobrin glacier. Although it takes all of the survival skills and resources Estraven has learned throughout his life, he gets Genly over the Ice and back to Karhide.

Why does Estraven do this? Because he believes in something no other Gethenian does. In a world where it is always the Year One, Estraven believes in progress. He is idealistic and thinks beyond the boundaries of Karhide and Orgoreyn which everyone else seems to be stuck inside. King Argaven, a madman, is quick to think of Genly as mad, or just a pervert. The Orgota bureaucrats, liars all, are quick to assume the same of Genly. Estraven, a dreamer, believes Genly is the way to achieve his dreams. It is said Estraven is a patriot, although his love of one land does not mean hatred of another. He is not just a Karhidian patriot but a Gethenian one, and this patriotism leads him to eventually give his life (abandoning the Gethenian taboo of suicide) so that Genly’s mission can be achieved.

Estraven’s dream does not end at his death. This is the purpose of the scene with Genly and Estraven’s son at the end. Genly arrives in Estre with news of Estraven’s death. Instead of wanting to hear about the story of crossing the Gobrin Ice, Estraven’s son Sorve wants to hear about the other worlds, and the other people living out there. Much like his father, Sorve looks forward and outward to the Ekumen and the future of Gethen. Although Estraven has died, there will be another generation of idealistic Gethenians who are ready to progress past Year One and the stagnation of their ancestors because of Estraven’s sacrifice.