I hope that by now you have discovered that this little piece of music is in the exact form as the Bach puzzle canons we have just so intensively studied.

 

(Think about the music again, if you have just discovered this.)

 

Therefore, "Canon a 2" must mean that there are two voices which are in a canonical relationship with each other. As the two visible voices are different, there must be a third, missing voice! which is performed as a canon with one of them.

 

But which one?

 

As the upper voice is more simple, could it be that the third voice is a transformed version of that voice?

 

And how is the missing voice to be performed?

 

Is there a [start here symbol], or any clefs in weird positions to help us answer this question?

 

No, so we are on our own, as in the two "Seek and ye shall find" canons at the end of the Musical Offering.

 

This, then, is a real musical mystery to be solved!

 

For those who really want a difficult musical challenge, try to solve the mystery without any hints.

 

Hints are provided here.