Meh. This book seems to not have aged well, if it ever did. There are a couple of interesting ideas, like the trick of hiding science in religion to have it survive the fall of the Empire. But with this book I have the same problem as with Ringworld: It's this gigantic world of possibilities, but all the stories are rather unconnected and play on a tiny scale. All of the four stories basically play out the same way: Bullish smart man tricks out some king by having science and technology. Apparently, in the far future, there's still kings and there's also no women. Maybe the rest of the books are better, but I won't find out. This one certainly doesn't deserve to be called a classic.