This gives Zhuangzi's Daoism less of the primitive thrust of the Daode Jing (the term wu-wei virtually disappears in the inner chapters).
Anything that we cannot see is expressed by the Chinese word wu pronounced woo.
Wei Ying-wu is probably addressing the daughter of some dead friend whom he has brought up in his own family, or she may be a poor relation on his mother's side, but that she is not his own daughter is clear from the fact that her clan name differs from his, which is Wei.
A great Chinese sage from my heritage, Lao Tzu, promoted a practice called wu wei, which means effortless being and doing.
Both the pitcher and batter start in the state that precedes Tai Chi called wu chi.