The direct and the indirect lead on to each other in turn. It is like
moving in a circle—you never come to an end. Who can exhaust the
possibilities of their combination?
The _T‘u Shu_ adds 哉. The final 之 may refer either to the circle
or, more probably, to the 奇正之變 understood. Capt. Calthrop is
wrong with: “They are a mystery that none can penetrate.”