Business Goals Law: Business objectives are the origin of every data mining solution. A data miner is someone who discovers useful information from data to support specific business goals. Data mining isn't defined by the tool you use.
Business Knowledge Law: Business Knowledge is central to every step of the data mining process. You don't have to be a fancy statistician to do data mining, but you do have to know something about what the data signifies and how the business works.
Data Preparation Law: Data preparation is more than half of every data mining process. Pretty much every data miner will spend more time on data preparation than on analysis.
No Free Lunch for the Data Miner: The right model for a given application can only be discovered by experiment. In data mining, models are selected through trial and error.
Pattern Law: There are always patterns in the data. As a data miner, you explore data in search of useful patterns. Understanding patterns in the data enables you to influence what happens in the future.
Insight Law: Data mining amplifies perception in the business domain. Data mining methods enable you to understand your business better than you could have done without them.
Prediction Law: Prediction increases information locally by generalization. Data mining helps us use what we know to make better predictions (or estimates) of things we don't know.
Value Law: The value of data mining results is not determined by the accuracy or stability of predictive models. Your model must produce good predictions, consistently. That's it.
Law of Change: All patterns are subject to change. Any model that gives you great predictions today may be useless tomorrow.