Wu Hsin repeatedly returns to three key points. First, on the phenomenal plane, when one ceases to resist What-Is and becomes more in harmony with It, one attains a state of Ming, or clear seeing. Having arrived at this point, all action becomes wei wu wei, or action without action (non-forcing) and there is a working in harmony with What-Is to accomplish what is required.
Second, as the clear seeing deepens (what he refers to as the opening of the great gate), the understanding arises that there is no one doing anything and that there is only the One doing everything through the many and diverse objective phenomena which serve as Its instruments.
From this flows the third and last: the seemingly separate me is a misapprehension, created by the mind which divides everything into pseudo-subject (me) and object (the world outside of this me). This seeming two-ness (dva in Sanskrit, duo in Latin, dual in English), this feeling of being separate and apart, is the root cause of unhappiness.