What is a schema? -- A new look at musical structure -- Style structures and musical archetypes -- Defining the changing-note archetype -- Schematic norms and variations -- A schema across time -- 1720-1754 : scattered examples -- 1755-1769 : sharp increases in population and typicality -- 1770-1779 : the peak -- 1780-1794 : new complications -- 1795-1900 : a legacy.