A central principle, although not one of the numbered rules, is found in the R&A rule book's inside front cover:
"Play the ball as it lies, play the course as you find it, and if you cannot do either, do what is fair. But to do what is fair, you need to know the Rules of Golf."
"The game of golf should be played in the correct spirit and to understand this you should read the Etiquette Section in the Rules of Golf. In particular:
• show consideration to other players
• play at a good pace and be ready to invite faster-moving groups to play through,
• take care of the course by smoothing bunkers, replacing divots and repairing ball marks on the greens."
The Rule Book also includes definitions of terms used throughout the rulebook (sometimes including examples of what does or does not meet a definition), and defines the use of particular words in context to clarify what is meant by the use of a word.
The Rules of Golf cannot be properly understood without understanding the specific Definitions.