Although science attempts to draw a clear line separating its endeavors from those of "pseudoscience," Henry Bauer reveals that the distinction is both equivocal and misleading. Setting aside science's snowy mantle of truth, Bauer presents pseudoscience—or anomalistics—not as the opposite of science but as something that develops parallel to it.
 
Science assumes anomalies—that is, phenomena that contradict the existing store of knowledge—result from error, contamination, or even deception: in short, from bad research technique, at best, and deliberate hoax, at worst. Anomalists, by contrast, accept such occurrences, often on the basis of eyewitness claims, as important in themselves and worthy of further study, even if they contradict prevailing theories and offer a minimal degree of reproducibility.
 
Science or Pseudoscience explores the diffuse and porous borders between mainstream and unorthodoxy. A scientist himself, Bauer points out that some phenomena that have turned out to be spurious, such as polywater and cold fusion, were for a time taken quite seriously by respected members of the scientific community. Other anomalies, such as ball lightning and meteorites, were dismissed by many scientists but turned out to be legitimate discoveries. Meanwhile, science has failed to prove that phenomena encompassed by the "big three" subjects in anomalistics—parapsychology, ufology, and cryptozoology (e.g., the Loch Ness monster)—do not exist. Rather, science theorizes that these phenomena cannot exist, since today's scientific laws seem to hold them to be impossible.
 
Bauer discusses anomalies such as archaeoastronomy (e.g., Stonehenge) and bioelectromagnetics and looks at how institutional, commercial, and political interests influence borderline research in mainstream laboratories. He also draws a distinction between fraud and commercial huckstering, on the one hand, and genuine knowledge-seeking about matters ignored by the established intellectual disciplines, on the other.
 
Bauer notes that the more closely anomalistic research approaches science, the more strenuously it is criticized by the establishment, often in terms of heresy. Reminding us that geniuses are cranks who happen to be right while cranks may be geniuses who happen to be wrong, Science or Pseudoscience offers a measured and thoughtful assessment of this volatile debate.