Saying yes to what feeds you emotionally and spiritually is essential for inner peace and well-being. Saying no to what drains your energy or pulls you off center is requisite for inner balance. Make your "yes" and "no" lists. Post them where you can see them easily — by the phone, perhaps — and update them frequently. They'll serve as an instant reminder whenever you're tempted to stray from your commitment to serenity.
— Joan Duncan Oliver, Happiness: How to Find It and Keep It