However, the yielding is important - but to be able to yield and retain balance, you must be sensitive. Sensitivity is the basis of all Tai Chi self defense, and is cultivated by pushing hands. This composite training teaches you to be sensitive to your opponent's movement and balance.
There is another fundamental principle that underpins sensitivity - stillness. But it is stillness of the mind, rather than the body. For if the mind is cluttered with wild emotions and intentions, you cannot hope to be able to detect subtle changes in balance and power. The best way to still the mind is regular meditation sessions.
So, the meditation practice that is regularly ridiculed by western culture, is to cultivate stillnes - which provides the basis for sensitivity, which enables you to defend yourself.