two & three-part [human] inventions

two-part structures

(less interesting, more divisive):

 east/westapollo/dionysusathens/jersusalemleft/rightsubjective/objectivedog person/cat person 

three-part structures

(more interesting, less divisive):

 in magic: the pledge, the turn, the prestigein music: the exposition, the development, the recapitulationin music: the concept, the composing, the piecein comedy: the premise, the set-up, the punchlinein food: the ingredients, the cooking, the mealin art: the art, the work of art, the work of the work of art