You can prime potential employers with what you wear to a job interview. You can prime the emotions of your guests with how you set the mood when hosting a party. Once you know priming is a fact of life, you start to understand the power and resilience of rituals and rites of passage, norms and ideologies. Systems designed to prime persist because they work. Starting tomorrow, maybe with just a smile and a thank-you, you can affect the way others feel—hopefully for the best.