Even with all the technological advances in this day and age, these ideas from 2500 years ago are being put to use in intelligence agencies around the world. Even some current definitions of intelligence are based on statements made in this chapter. "What enables the wise sovereign and the good general to strike and conquer, and achieve things beyond the reach of ordinary men, is foreknowledge" (Tzu 77). He breaks the use of spies into five classes, and explains the importance of how to handle each class. The five classes are local spies, internal spies, converted spies, doomed spies and surviving spies. Most information on spies is lost, buried or classified; and if a spy does their job right, nobody would know of their encounters. This being said, it is difficult to draw conclusions on which spies completed which action, or what class they were considered to be in. Sun Tzu finishes his book with these sentences.
Hence it is only the enlightened ruler and the wise general who will use the highest intelligence of the army for purposes of spying, and thereby they achieve great results. Spies are the most important element in war, because upon them depends an army's ability to move (Tzu 82).
From that point forward, spies have been used in almost every civilization to gain intelligence on not only their enemies, but also themselves. Understanding the ideals in this book has guided multiple armies and nations to a successful future. Even in times of peace, Sun Tzu believes in the importance of intelligence. "In peace prepare for war, in war prepare for peace. The art of war is of vital importance to the state. It is a matter of life and death, a road either to safety or to ruin" (Tzu 9). The voyage to explore the new world was one of gathering intelligence, to expand and sustain the British way of life. When they landed and started the first colony, ideas of a revolution were already stirring.
