Concept
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. The general public has difficulty distinguishing between science and its imitators, 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. The boundary between fringe science and pseudoscience is disputed. The connotation of "fringe science" is that the enterprise is rational but is unlikely to produce good results for a variety of reasons, including incomplete or contradictory evidence. Pseudoscience, however, is something that is not scientific but is incorrectly characterised as science. The term may be considered pejorative. For example, Lyell D. Henry Jr. wrote that, "fringe science [is] a term also suggesting kookiness." This characterization is perhaps inspired by the eccentric behavior of many researchers of the kind known colloquially (and with considerable historical precedent) as mad scientists. Although most fringe science is rejected, the scientific community has come to accept some portions of it. One example of such is plate tectonics, an idea which had its origin in the fringe science of continental drift and was rejected for decades.