The Chinese classic "The Master of Demon Valley" was written around 500BC (similar time to the Sun-Tzu's Art of War). It's associated with an obscure school of thought known as Tsung-heng hseuh, which could be read as "the learning of freedom of thought and action". The extract below ends the text and gives a taste of the book. "The Master of the Hidden Storehouse" follows it.
"That is why petty people imitating others will use this in a perverse and sinister way, even getting to the point where they can destroy families and usurp countries.
Without wisdom and knowledge, you cannot preserve your home with justice and cannot preserve your country with the Way. The reason sages value the subtlety of the Way is true because it can change peril into safety, rescue the ruined and enable them to survive"
An excellent book for any martial arts student interested in the art of conflict, business people in the art of business and psychological strategy. Learn the art of winning a fight without fighting. Thomas Cleary books are a must have.