Leon Greco nearly drowned and fell into coma. His anoxia was treated with an experimental drug regenerating his damaged neurons and giving him superior intelligence and improved motoric skills as side effects. He uses his new capabilities to learn and understand in a way that no normal human could do, setting him aside from the rest of humanity after following treatments. Eventually, he finds out that there is another one of his kind but with a different concept: One who doesn’t seperate himself from humanity but tries to rescue it whereas Greco’s understanding is that humans are only tools. A spectaculous confrontation starts.
Ted Chiang is a modernized re-telling of the somewhat dated 1958 novel „Flowers for Algernon“ by Daniel Keyes. There are not intelligent rats involved. Instead, Chiang uses his Computer Science knowledge to extrapolate his ideas about hyperintelligence. In Keyes‘ story, there also is no adversary to contrast two different forms of posthuman directions. But in the end effect, it follows similar plot lines.
I found this story entertaining in a similar way like Hofstadter’s „Gödel, Escher, Bach„: very thought provoking (if one raises far beyond human intelligence, does one also grow out of human morality?), highly intelligent; it pushes the reader to the extreme in his explanation of hyperintelligence, something that cannot be really understood, and he pushes it a bit over the top. Yes, it was fun to read, but after a while, I could have left and said „nice infodump, I understood, but now I want to continue the plot“. Which is lacking other essential story elements, like emotions or dialogue, by the way. Insofar, it started very good, but lost traction quite soon.
I consider it far inferior to Flowers for Algernon which is very moving and memorable. I’d recommend „Understand“ as a kind of modern companion, one that concentrates more on the „Science“ side of SF whereas Flowers for Algernon is more on the narration side.