Be careful, the other review gives a huge number of spoilers.
This book was written during Silverberg's middle period, when his writing was at it's peak, both in terms of prose technique and content with well drawn adult characters, insights, and interesting themes. If you enjoy middle period Silverberg (when he was flitting at the edge of the 'new wave') when he was writing books like "Tower Of Glass" & "Thorns" & "Born With The Dead" & "Shadrach In The Furnace" then you will enjoy this book.
I found the first ten pages of so fascinating, then the next 30 seemed a little like filler - typical near future SF stuff to place the book clearly into the genre - and from then on it's a page turner.
I don't think I'm giving too much away in saying this is a sciece fictional riff on Faust. And don't be put off by that description, which would not have enticed me, it is well done.
This book was Ok. It takes place in a pre-apcolyptic New York. It's about developing precognative powers and how the power of it could be enticing. It's also about free will. Do you lose it when you begin to see the future? Do you try and stop the future? The main character never tried. He did as he was told and "followed the script". He uses the precog powers to put a man he admires into the future presidency. But he ends up seeing him as a tyrant, another Hitler, after he's helps set things into motion. The ending of the book seemed rushed I guess. And the political part of the book, long. It picked up when the year 2000 was ushered in (this book is old). But it kept me interested for the most part.