Why do people accept ideas that are contradicted by science or logic? In Implausible Beliefs, Allan Mazur offers a comparative look at the nature of irrational belief systems, their social roots, and their cultural and political impact. He begins by providing standards for judging beliefs implausible and assessing the impact of such belief systems onpolitics and social policy in the US. Mazur describes and defends commonsense criteria for establishing that certain views should not be sustained in the face of present-day understanding. He presents a statistical portrait of implausible beliefs rampant in the US, and who tends to accept them.

Mazur applies criteria for implausibility to the Bible, astrology, and visitation to Earth of intelligent beings from other worlds. Pointing out that everyone "knows" the Bible but few actually read it, the author scrolls through the first five books of the text, noting points that undermine the scripture's natural history and moral guidance. Working on the assumption that implausible religious views are fundamentally no different from implausible secular views, he critiques secular beliefs in astrology and UFOs. Mazur concludes the volume with an attempt to explain why most people accept implausibility—some more than others—despite evidence and logic that refute them.

Looking to mainstream sociology and psychology, Mazur shows how children are socialized into such beliefs, and how adults are influenced by spouses and friends. Personality is also a factor, sometimes abetted by stressful or lonely life situations. Lucidly written, this is a provocative and informative contribution to social psychology, sociology, religion, political science, and American studies.