Why are the light and dark parts of the yin-yang separated by a curving line and not a straight line ?

because the Earth is in shape of circle and it Move regularly around the sun and moon is moving surrounding the earth when night be gains to one part of earth other side create a curving line as the earth is also surrounding and moon come surrounding in between with the son and earth being in round shape of the moon Create a curving sad ow on in side the earth.

lol I like to think they got the idea from spooning, but I know they didn't. The feminine curve would represent spirit who not only connects, but is one with all.

to represent the fact that they are interconnected and interdependent, and flow within and around one another. one cannot exist without the other. it is an infinite cycle in which they wallow, hand in hand, spinning onward into the vastness of eternity.

To represent that they are opposites. One may seem upside down an one upside right.

It must be something female, bcos in all sacred geometry, the curve represents the female.....

Because they like to mingle as they do in life.

Because they are intertwined into each other?