A modern system of magic, with roots equally entrenched in Victorian mysticism and quantum physics. Most interesting for the "metabelief" that beliefs are tools to an end, which can be changed to suit the desired end.

According to Peter Carroll in the Principia Chaotica:
     In Chaos Magic, beliefs are not seen as ends in 
     themselves, but as tools for creating desired effects. 
     To fully realize this is to face a terrible freedom in 
     which Nothing is True and Everything is Permitted, 
     which is to say that everything is possible, there are
     no certainties, and the consequences can be ghastly. 
     Laughter seems to be the only defence against the 
     realisation that one does not even have a real   

Practicing Chaos Magic involves the temporary adoption of an obsessive belief system that allows for the possibility of magic to accomplish specific effects, and then the abandonment of that belief system upon the completion of the work. Subsequent, and even contradictory belief systems are adopted in turn as need or desire may dictate. To do this (and not go completely insane) it is of paramount importance that no one particular set of beliefs is ever accepted as being ultimately true.