being wrongly placed after his grandson Tu Mu.

5. TU MU (803-852) is perhaps the best known as a poet -- a
bright star even in the glorious galaxy of the T`ang period. We
learn from Ch`ao Kung-wu that although he had no practical
experience of war, he was extremely fond of discussing the
subject, and was moreover well read in the military history of
the CH`UN CH`IU and CHAN KUO eras. His notes, therefore, are
well worth attention. They are very copious, and replete with
historical parallels. The gist of Sun Tzu's work is thus
summarized by him: "Practice benevolence and justice, but on the
other hand make full use of artifice and measures of expediency."
He further declared that all the military triumphs and disasters
of the thousand years which had elapsed since Sun Tzu's death
would, upon examination, be found to uphold and corroborate, in
every particular, the maxims contained in his book. Tu Mu's
somewhat spiteful charge against Ts`ao Kung has already been
considered elsewhere.

6. CH`EN HAO appears to have been a contemporary of Tu Mu.
Ch`ao Kung-wu says that he was impelled to write a new commentary
on Sun Tzu because Ts`ao Kung's on the one hand was too obscure
and subtle, and that of Tu Mu on the other too long-winded and
diffuse. Ou-yang Hsiu, writing in the middle of the 11th
century, calls Ts`ao Kung, Tu Mu and Ch`en Hao the three chief
commentators on Sun Tzu, and observes that Ch`en Hao is
continually attacking Tu Mu's shortcomings. His commentary,
though not lacking in merit, must rank below those of his
predecessors.