Storyline: 2/5 
 Characters: 1/5 
 Writing Style: 2/5 
 Resonance: 2/5 
 My estimation of this 1973 book is surely tainted by the fact that I read it in 2015. Time travel storylines are rather commonplace now, and this book reminded me of how much I don't like them. The story verged on hard science fiction; in fact, the repeated attempts to explain how time travel works takes up a large part of this work. Despite this, Gerrold glides over the problems and paradoxes of time travel that threaten his conception of it. This made for a strange mix of metaphysics explication with a request for the suspension of disbelief on those very ideas it was exploring. 
 The book was supposed to be provocative in an another area as well: identity. Without any attempt at subtlety, it confronts the reader with gender, sexual, and relational roles that are unorthodox, if not outright shocking. I understand that one of the many functions of art is to probe the borders of what is acceptable, but this part of the book, to me, was an example of an author using his artistic license to delight in perversity. 
 There were some merits in the end, however. The concept of a baseline and the reasons why one would remain close to it are especially thoughtful and intriguing. For those who have always been intrigued by the paradoxes of time travel, then, this story does offer some ideas that haven't been overused by Hollywood in the intervening years between the book's publication and this review.