Gardner acknowledges that such cases occurred, and describes some of them, but says that times have changed: "If anything, scientific journals err on the side of permitting questionable theses to be published".

Gardner acknowledges that "among older scientists ... one may occasionally meet with irrational prejudice against a new point of view", but adds that "a certain degree of dogma ... is both necessary and desirable" because otherwise "science would be reduced to shambles by having to examine every new-fangled notion that came along."

These psychological traits are in varying degrees demonstrated throughout the remaining chapters of the book, in which Gardner examines particular "fads" he labels pseudo-scientific.

As per the subtitle of the book, "The curious theories of modern pseudoscientists and the strange, amusing and alarming cults that surround them" are discussed in the chapters as listed.

For example, in the article, Gardner writes: The reader may wonder why a competent scientist does not publish a detailed refutation of Reich's absurd biological speculations.

[12] A contemporary review in the Pittsburgh Post-Gazette particularly welcomed Gardner's critical remarks about Hoxsey Therapy and about Krebiozen, both of which were being advanced as anti-cancer measures at that time.

Louis Lasagna, in his book The Doctors' Dilemmas, considered it to be a "superb account of scientific cults, fads, and frauds" and wrote that "This talented writer combines solid fact with a pleasing style.

In The Quest for Wilhelm Reich Wilson wrote of this book(Gardner) writes about various kinds of cranks with the conscious superiority of the scientist, and in most cases one can share his sense of the victory of reason.

[17] In February 1989 Gardner wrote a letter published in The New York Review of Books describing Wilson as "England’s leading journalist of the occult, and a firm believer in ghosts, poltergeists, levitations, dowsing, PK (psychokinesis), ESP, and every other aspect of the psychic scene".

[18] Shortly afterwards, Wilson replied, defending himself and adding "What strikes me as so interesting is that when Mr. Gardner—and his colleagues of CSICOP—begin to denounce the 'Yahoos of the paranormal,' they manage to generate an atmosphere of such intense hysteria ...".

[17] Gardner in turn replied quoting his own earlier description of Wilson: "The former boy wonder, tall and handsome in his turtleneck sweater, has now decayed into one of those amiable eccentrics for which the land of Conan Doyle is noted.

They prowl comically about the lunatic fringes of science ..."[17] In a review of a subsequent Gardner work, Paul Stuewe of the Toronto Star called Fads and Fallacies a "hugely enjoyable demolition of pseudo-scientific nonsense".