In popular parlance, a truther is someone who believes in or advocates ideas which are popularly believed to be nonsense. The Orwellian nature of this usage, and consequently its effectiveness as a tool of propaganda and disinformation, seems to have escaped the notice of many people.
"Truthers" generally seem to appear as part of "movements", each of which seems to serve one of the two following functions:
- a propaganda campaign to persuade people that a particular belief (typically false) is true -- generally because that belief favors the status quo or supports the establishment agenda in some way
- a disinformation campaign to discredit a particular belief (typically one for which there is substantial but inconclusive evidence) through straw-man advocacy -- generally because that belief is in some way threatening to the establishment or its agenda
Since then, the term has slowly gained currency in reference to other minority positions, many of them truly unscientific and irrational but not always so.