The book posits that astrology is a valid system of knowledge based on celestial-terrestrial correlations and personality correspondences, arguing that scientific opposition to the field is rooted in bias rather than empirical refutation. The authors, Jan Gerhard Toonder and John B. West, approach the subject from a position of advocacy, utilizing historical context and critical analysis to challenge the prevailing skepticism within the scientific community. They aim to dismantle common arguments against astrological practice by highlighting perceived inconsistencies in the methodology of its detractors.

This text is recognized primarily as a polemic work that serves as a foundational reference for proponents of astrology seeking to counter scientific skepticism. Readers often note that the prose is highly argumentative and reflects the specific ideological climate of its publication era rather than contemporary scientific discourse.