C�dric Tiberghien has long been interested in the principle of Beethovenian variation, as is demonstrated by a recording he made for harmonia mundi twenty years ago. He now proposes a project on a quite different scale, in which all Beethoven's variation cycles will be juxtaposed with works illustrating the evolution of the genre, from the Renaissance to the present day. Here is the first part of a trilogy that promises to be fascinating.