Art of War 1.25

This seems to be the way in which Ts‘ao Kung understood the passage, and is perhaps the best sense to be got out of the text as it stands. Most of the commentators give the following explanation: “It is impossible to lay down rules for warfare before you come into touch with the enemy.” This would be very plausible if it did not ignore 此, which unmistakably refers to the maxims which Sun Tzŭ has been laying down. It is possible, of course, that 此 may be a later interpolation, in which case the sentence would practically mean: “Success in warfare cannot be taught.” As an alternative, however, I would venture to suggest that a second 不 may have fallen out after 可, so that we get: “These maxims for succeeding in war are the first that ought to be imparted.”