Hello Ronintetsuro,

My understanding of conspiracy was shaken radically when I heard a recording of a talk given by Lance deHaven-Smith, Professor for Public Administration and Policy at Florida State University (Edit: updated timestamp) . I will do my best to paraphrase what he says:

1. Conspiracy is a valid legal concept in many jursidictions. We use it all the time to denote groups of people coming together to commit crime. It is not some marginal, esoteric concept that belongs to the tin-foil-hatted.

2. Conspiracy Theory (and by extension Theorist as one who ascribes to it) has come to denote, usually with negative connotations, for a hypothesis that some result is the effect of a collusion of individuals participating in a Conspiracy.

3. Blanket rejection of all conspiracy theories essentially supports either a theory of one individual's action: the notion that the effect in question was achieved by a single person; or coincidence: the notion that said result is the effect of unrelated, uncoordinated forces.

Under this framework, the official explanation for the events that occurred on the morning of September 11th, 2001 is in fact a theory that suggests conspiracy - many hijackers conspired to act simultaneously to overtake several aircraft and fly them into prominent buildings.

Of course the above example is not what is meant when the term 'Conspiracy Theory' is thrown around in public discourse. The term has come to mean something more akin to a loosely supported paranoia about dominant groups or paradigms.