Cryptozoic!

Imagine a world where time travel is possible: with the aid of a drug that unlocks the powers latent in the human mind, men can travel far back in time to prehistoric ages. There they can see the world, but cannot hear it; they can observe, but are unable to interact with the world. It is to this world that Cryptozoic! takes us. Brian Aldiss takes us into the mind of one such time traveler, Edward Bush--an artist and the best time-traveler of his era. But the story focuses less on the actual time traveling than it does on the awakening of this artist to the reality of the nature of the world he lives in. As his "present" time world of the 2090s falls into the hands of a dictator who seizes control of the time travel drug, Edward Bush tries to escape into the past, but then the plot thickens...

I'll try not to give too much away. The book starts off a little slow, but picks up pretty quickly. Aldiss does a good job of avoiding the paradoxes that plague most time travel stories. In fact, until the last few chapters of the novel, I was about to call this the best time travel book I've read. But the last few chapters take a terrible turn for the worse--the book degenerates into random philosphizing about the nature of time. And Brian Aldiss makes the mistake of reintroducing the time travel paradoxes that he had so cunningly avoided previously.

However, it is a competent story that I felt was worth my time to read. There are plenty of better books you could read, but there isn't anything wrong with this one. I neither recommend nor not recommend this book.