The terms chèng (1) and ch'í (11) present a perplexing problem for the reader or translator of texts in traditional Chinese military thought. In nonmilitary contexts chèng is rendered by a range of expressions including 'upright, true, orthodox, correct, regular, authorized, exact, straight, formal, just, at the time of, during, to adjust, principal, original, obverse', ch'í is translated 'strange, wonderful, rare'; the same graph read chī is translated ‘odd, single, surplus’.