Toivo Bach two part invention no. 8

Bach wrote these pieces for students, but the inventions are actually some of his best keyboard music. They are written for developing two voices independent but simultaneously interacting with each other at the same time. Each invention has a trick or idea in mind; in this case it is the arpeggios and broken arpeggios
that create the lesson here. Although as a student, these pieces are so fun to play one doesn't really realize it has a pedagogical purpose to it. This is the beauty and genius of the inventions.