Sometimes it takes years for a salesperson to learn the basic rules of the game because no one has written them down. Or at least no one has written them down as “rules.” Older salespeople while training the new ones will often impart these gems of sales wisdom, but most sales training courses only touch briefly on some of these principles and then only in passing. Jill Konrath, author of Selling to Big Companies has enumerated The Seven Paradoxical Sales Principles, all of which may be found in the unwritten, unpublished Old Salesman’s Book of Knowledge.