Principles is a thought provoking book in that it gets one to think of running a business like running a machine. Invest in computers and programming to perform checklist tests constantly so you can ensure your business is operating in the manner you expect. This will require you to think hard about how you expect your business to work. It will also allow you to identify what activities really require your attention.

The Visual Display of Quantitative Data is great as it gets you thinking about different ways to present ideas effectively. The map of Napoleons march to and from Russia is exquisite.