Just read the short story. I'm glad I did. Thanks.
If you're at all interested in this story then the full novel is definitely worth reading, it's not very long. One of my all time favorite books.
I read it many years ago- it is well written but has a terrible message, and is a really good example of how much good writing can be used to deliver bad messages. The essential lesson is that being smarter can be much worse, unintended consequences, hubris of humanity, etc. And as is often the case with this sort of thing, rather than actually examine the implications of a technology that would make people smarter, it has to turn out that the effect is only temporary. Why? Because otherwise the deck wouldn't be stacked the way Keyes wants it to be stacked.
Daniel Keyes, the author of the short story Flowers for Algernon, and a novel of the same title that is its expanded version, died three days ago.
Keyes wrote many other books in the last half-century, but none achieved nearly as much prominence as the original short story (published in 1959) or the novel (came out in 1966).
It's probable that many or even most regulars here at Less Wrong read Flowers for Algernon: it's a very famous SF story, it's about enhanced intelligence, and it's been a middle/high school literature class staple in the US. But most != all, and past experience showed me that assumptions of cultural affinity are very frequently wrong. So in case you haven't read the story, I'd like to invite you explicitly to do so. It's rather short, and available at this link:
Flowers for Algernon
(I was surprised to find out that the original story is not available on Amazon. The expanded novelization is. If you wonder which version is better to read, I have no advice to offer)
(I will edit this post in a week or so to remove the link to the story and this remark)