This story takes place on an alien planet ruled by felinoid aliens on the verge of an industrial revolution, who less than 100 years earlier have discovered and enslaved humans. The main character, Heao, is an Academe, one who studies and uses what we consider accepted scientific methods to advance society, who often find themselves at odds with the guardians, who try to conduct their lives based on pseudo-religious beliefs.
Heao meets up with Baltsar, a merchant, and after interacting with his slaves and studying them for a time, she concludes that the slaves are more intelligent than was previously believed. Unfortunately, her findings prove to have unanticipated political consequences that cause her to be shunned by her society, even some of her closest friends, in a sort of Galilean persecution, even as she and her associates seek funds for an expedition that might shed some light on the issues. The story takes a surprising turn as the situation is played out. The book is very thought provoking in issues of slavery, and of how science and religion sometimes conflict with one another.