While Lem is probably most famous for writing the source novel to Andrei Tarkovski’s film Solaris, my first introduction to his work was His Master’s Voice, which I read for a sci-fi literature course taught by Eric Rabkin at the University of Michigan. It’s a novel that still sticks with me twenty years later. It’s the story of what happens when a message from the stars is received and how it impacts the lives of the scientists who are tasked with secretly decoding it. I remember that it opened my mind to what sci-fi could be. To me it wasn’t science fiction, it was philosophical fiction, and deeply fascinating. I need to reread it now that I’ve read more philosophy. I wonder if it will leave me with the same impression. After I reread Heinlein’s Stranger in a Strange Land, I was a bit disappointed, as I had grown in depth, while the story hadn’t.
Another interesting novel is The Futurologial Congress. I won’t even bother trying to explain its wild, fever dream plot.