"I don't worry too much about the fundamentalist principles that are in almost any discussion about jazz"

Pat Metheny's quote recommends that he does not take too seriously the fundamental principles of jazz that are often talked about. He is likely referring to the conventional guidelines and conventions of jazz music, such as using certain instruments, scales, and rhythms. Metheny is suggesting that these guidelines need to not be taken too seriously, and that jazz artists must be totally free to check out and experiment with various sounds and styles. He thinks that jazz ought to be an open and imaginative form of music, which artists need to be motivated to press the borders of the category. By not stressing too much about the fundamental principles of jazz, Metheny is encouraging artists to be creative and to explore new ideas. He thinks that this is the very best way to keep jazz alive and dynamic.