The only way to know how a complex system will behave-after you modify it-is to modify it and see how it behaves.

The benefits provided by worker participation are twofold. Quality is improved because of the finding and fixing of a very large number of problems, but also, and perhaps equally important, moral is improved.

All models are wrong, but some are useful.

Management must provide employees with tools that will enable them to do their jobs better, and with encouragement to use these tools. In particular, they must collect data.

The business of the statistician is to catalyze the scientific learning process.

Remember that all models are wrong; the practical question is how wrong do they have to be to not be useful.

Discovering the unexpected is more important than confirming the known.