So there appears to be an astrology tag with very few questions. This somewhat represents mythology around cancer specifically.
Why does the astrology sign for cancer seem to represent a yin and yang?
According to this
This is also seen as two crab's claws, intertwined in a way which represents the dual nature of the Cancerian personality. In this form, it would be understood as similar to the Asian Yin and Yang symbol.
Is this all there is to it?