This quote is hanging on my desk at work. I've always taken it as the main guiding principle of my approach to customer service throughout my career. It tells us that true strength is not in bellowing as loudly as you can - it is in deliberate action, deliberate words, and speaking with a non-aggressive authority which demands your attention. It also reminds us that when customers resort to being rude, they are not exerting power over you. They are resorting to the only tool in their arsenal - the temper tantrum.