7. Hence the use of spies, of whom there are five classes: local spies; inward spies; converted spies; doomed spies; surviving spies.

故用間有五有鄉間有內間有反間有死間有生間

Sun Tzu

Sun Tzu identified five types of spies that can be used in warfare: local spies who are native to the area of operation and have knowledge of the local terrain and culture; inward spies who are working within the enemy’s organization and can gather information about their plans and intentions; converted spies who were originally working for the enemy but have been turned and are now working for the opposing side; doomed spies who are intentionally sent on a mission with the understanding that they will not be able to return and may be sent on a suicide mission or to gather particularly dangerous information; and surviving spies who are able to complete their mission and return with valuable information. Sun Tzu emphasized the importance of using spies effectively, as they can provide valuable intelligence that can be used to gain an advantage over the enemy.

Hence the use of sources, of whom there are five classes: local sources; inward sources; converted sources; doomed sources; surviving sources.

Using sources, or spies, can provide valuable insight into the inner workings of a rival company or the potential success of a new product or strategy. There are five general classes of sources, these are:

1. Local sources: These are sources of information that are native to the area in which the business operates. They may have connections and knowledge of the local market, industry, and business environment, which can be valuable in gathering intelligence.
2. Inward sources: These are sources of information that are within the competitor’s business or its organization. They may be employees, contractors, or partners who have access to internal information about the competitors’ operations, plans, and strategies.
3. Converted sources: These are sources of information that were originally working for a competitor or outside organization, but have switched to working with the business. They may have valuable insights into the operations and strategies of the business’s competitors.
4. Doomed sources: These are sources of information that are used on a one-time basis, with the understanding that they may not be able to provide information again in the future. They may be used for risky or difficult missions, or to gather particularly sensitive or valuable information.
5. Surviving sources: These are sources of information that are able to provide valuable information on an ongoing basis. They may be able to provide valuable insights into the business environment, market trends, and the operations of competitors.

Businesses should use various types of sources to gather intelligence and gain an advantage in the market. These sources can come from different sources and have different levels of access to information, and can be used to gather valuable intelligence that can help the company make informed decisions.