Yin and Yang

[sdi]

Here is a construction of the most common modern taijitu (Yin and Yang) figure, using twelve circles. It is not very elegant—I have the feeling it could be constructed using fewer—but it's the best I've managed so far.

The interesting lesson here, if there is any, is that it's much simpler to double (or triple, etc.) a length than it is to half (or third, etc.) it.