Sun Tzu

Sun Tzu was an influential Chinese philosopher and military strategist, most famous for writing The Art of War. He lived two and a half thousand years before the 1930s. (PROSE: The Shadow of Weng-Chiang)

The Doctor claimed to have met Sun Tzu twice, (PROSE: The Shadow of Weng-Chiang) once with Ace, in his seventh incarnation. (AUDIO: The Shadow of the Scourge)

By his fourth incarnation, the Doctor owned one of Sun Tzu's original handwritten manuscripts for The Art of War. He had tried to convince the strategist to flesh out a central concept — it being "a greater honour to defeat the enemy without resorting to battle" — into a longer paragraph, so that readers would not ignore it. (PROSE: The Shadow of Weng-Chiang)

The Doctor later replaced Sun Tzu as the Chinese Emperor's military advisor, but held conflict resolution seminars instead of fighting. (PROSE: Set Piece)

The Doctor's ninth incarnation mentioned Sun Tzu on a list of warriors Rose Tyler can meet. (TV: The Love Invasion)