Fringe science refers to ideas whose attributes include being highly speculative or relying on premises already refuted. Fringe science theories are often advanced by persons who have no traditional academic science background, or by researchers outside the mainstream discipline.: 58  The general public has difficulty distinguishing between science and its imitators,: 173  and in some cases a "yearning to believe or a generalized suspicion of experts is a very potent incentive to accepting pseudoscientific claims".

The term "fringe science" covers everything from novel hypotheses which can be tested by means of the scientific method to wild ad hoc hypotheses and mumbo jumbo. This has resulted in a tendency to dismiss all fringe science as the domain of pseudoscientists, hobbyists, and quacks.

A concept that was once accepted by the mainstream scientific community may become fringe science because of a later evaluation of previous research. For example, focal infection theory, which held that focal infections of the tonsils or teeth are a primary cause of systemic disease, was once considered to be medical fact. It has since been dismissed because of lack of evidence.

 

Note:   The above text is excerpted from the Wikipedia article Fringe science, which has been released under the GNU Free Documentation License.