In placing European music within the wider frame of global music, we have lately begun to revise our views on certain processes of composition which have until now appeared axiomatic and unchangeable. One of these views was that early polyphony underwent a slow and toilsome evolution, emerging from the preceding monophony which was considered the more primary utterance of man. But the history of medieval music has taught us repeatedly how artful a monodic song can be and how artless, indeed primitive, the first attempts at polyphony had been, that is, if we would rely on written sources only. History does not proceed stepwise, and musical artifacts do not indicate a tidy rational progression from monophony to part-singing in two, three, or four voices. Co-existent, and presumably even older than monophony, are certain basic forms of polyphony, such as the bourdon.