Robert Silverberg certainly qualifies as a legend. He is one of the writers (along with Asimov, Pohl, and handful of others) who brought the genre of science fiction into the popular consciousness. He has won multiple Hugo and Nebula awards for his copious writing.
Time Hoppers is not one of his best stories.
The book promises to explore the paradoxes involved with time travel (a topic that’s interested me since I watched Back to the Future as a kid and one we’re still exploring today in movies like Looper). Instead of fleshing out these paradoxes, the book devolves into a cautionary tale about classism with an unlikable protagonist at the helm.
The most interesting part of this book was considering how a person in 1967 thought society would develop. With the rise of the super-rich and the growing divide between rich and poor, he may have been on to something.
—Robert Silverberg, The Time Hoppers (New York: Belmont, 1974).