What the taiji symbol depicts so beautifully is that as well as Yin and Yang twisting and twining around each other, they also each contain the other. Pure Yin, as soon as it is proposed, thought, conceived, allowed, already contains a taint of Yang; and vice versa. This is a natural law – the impossibility of absolute purity (or absolute anything for that matter). In taiji we say "Hardness comes from softness", or "Taiji is the art of concealing hardness with softness" – there is always an understanding that one comes from the other. This is very difficult to fully grasp – embody – it requires my mind to become the container of Yin and Yang, rather than focusing on or preferring either one. My mind stands back and envelops, and lets Yin and Yang play it out, like two children. This is yielding mind.