What is time? Where does it go? How much of it has passed, and how much is yet to come?

Worlds, both fictional and real, are immensely varied and strange. Why should their pasts be sensible, organized, and predictable? Why should fictional evolution follow a logical progression? Our world certainly didn’t.

This book features:

- 100 Speculative Ages
- Ideas for Using Them
- Notes on Time and Perspective
- Black and White Illustrative Figures