Here are some great teachers and players thoughts or philosophy about brass playing and learning to play music in general. Part of it will show different opinions and part of it will show similarities, like the thinking of Jacobs and Adam.
Arnold Jacobs says: "Song,to me, involves about 85 percent of the intellectual concentration of playing an instrument, based on what you want the audience to hear..... The remaining 15 percent is the application of the breath, wind, to fuel the vibration of the lips."
Bill Adam says: "Today I believe that ninety per cent of all playing is mental and the last ten per cent of the physical will be divided into nine percent breath and one per cent embouchure."

          Arnold Jacobs:  Song & Wind
Bill Adam: "approaches to problem solving"
Barry Green: "Quotes from The Inner Game of Music"
Herbert L. Clarke: "perfecting the little things first"
Rafael Mendez:  "good or bad habits"
Donald S. Reinhardt: mental attitude
primary playing factors
Chase Sanborn:  Off To A Good Start
Matt Graves:  "Teaching Philosophy of Claude Gordon"
Eddie "Tiger" Lewis:   Teaching come back students
Jeanne G. Pocius: ..the eternal airstream
Inner Teachers