Yin and Yang are interlinked

Yin is the inside space of a cup;it wouldn't be a cup without it.Yang is the cup.The coffee's heat, however, is yang,and its blackness is yin.Yang goes berserk sometimes,but there's some very powerful yins, too,if they don't quite go berserk.Yin is the darker swirl, the female,but there is a white dot in it.And yang is the lighter, the male,but it has a black dot.Water flowing calmly in a river is yin,but when it goes over the waterfall,it's very yang.Toothpicks are yin compared with a telephone pole.The back of a person is more yang than the front.The top of a person is the yang end.