This is from my Books page, on which you will find reviews of all of my favorites.
“You can know how to win through strategy with the long sword, but it cannot be clearly explained in writing. You must practice diligently in order to understand how to win.”
I found Musashi through my readings of Robert Greene, and his theories on strategy (aside form the sword-fighting techniques he shares within) are worth the time spent reading this book.
Musashi stresses over and over the importance of a practice and self-studying for any person seeking to become a master strategist, no matter the field of study: the book and the words of the experts alone will not make you good until you are actually practicing and learning, gaining a feel for yourself.