Rules and Other Rules

"...some rules for the conduct of life are matters of right and wrong, substantial, essential, and other rules for the conduct of life are matters of convenience, of form, of method, desirable but not essential." - Elihu Root 1846-1937

Quoted in "The First Triumph - How Five Americans Made Their Country A World Power," by Warren Zimmermann. P. 143

(Very good book, BTW. The Big Five are E. Root, T. Roosevelt, John Hay, Henry Cabot Lodge, and Alfred Mahan.)