An excellent science fiction book. It gives a vision of a probable far future of the humankind, in which all the galaxy is populated and unified in a single great empire. But this empire is about to fall and only one man knows it. Once you start to read and begin to understand what's going on, you'll always want to know what's next. Generations will pass, important characters will become leyends, but the story goes on and you just can't put it down.
I didn't give it 5 points because it's a little bit out of date, and some "ultra-futuristic" technologies described are already available nowadays, or just too old to be seen as the ultimate technology within 10.000 years... after all, it was written in the 1940's.