Crank

From RationalWiki

Crank is a pejorative term applied to someone who holds extremely unorthodox views on a subject and feels compelled to repeatedly try and tell the world about it. No amount of evidence contrary to the crank's view point will cause the crank to question his beliefs. The crank is usually an amateur in the field he is arguing against, but sometimes individuals with expertise in that field will go off the deep end (often medical or psychological issues can be traced to the point where an expert become a crank, such as strokes, nervous breakdowns or schizophrenia).

Cranks emerge in all fields of study and claim all kinds of crazy ideas, from being able to square the circle with a pencil and a compass, to biblical literalists in the creationism movement.

Synonyms include kook and crackpot (the latter of which has led to the creation of the term "psychoceramics" as the name of the study of such people).

[edit] Famous cranks

Well known cranks and their ideas include (links to their sites included until we have full articles here):

Neal Adams - Expanding earth
John A. Davison - Proscribed evolution
Eleni Papadopulos-Eleopulos, Peter Duesberg - AIDS denialism
Duane Gish - creationist writer and professional debate-mangler
David Icke - Alternate history, alien races, conspiracy theories
Richard C. Hoagland - "Face" on Mars, aliens, NASA conspiracy theories.
L. Ron Hubbard - Alternate history, alien races; founder of Scientology
Gene Ray - Time Cube
Viera Scheibner - Anti-vaccinationist
Andrew Schlafly - Creationism, abortion causes breast cancer, liberalism causes all societal ills, revised chronology, AIDS denialism, and many more. (But he's not really "famous", even in inverted commas)
Zecharia Sitchin - Reinterpreter of Sumerian mythology and perpetuator of the "Zeta Reticuli" alien conspiracy theory
Immanuel Velikovsky - Planetary catastrophism, a revised chronology, and more
Ernst Zündel - Holocaust denial
Most everyone on this list