As a life coach, I’ve always been intrigued by a person’s ability to change the mood of the people around you – your family members, friends, colleagues and yes, even strangers. Anyone who works in an open-plan office will have witnessed the impact an irritated colleague can have on all those in the vicinity, and, of course, the same holds true for those who are positive and upbeat. Your attitude can have a ripple effect on others, and truly can change another person’s day.I experienced this firsthand earlier this week, while paying for a few groceries at a supermarket – a regular, somewhat mundane experience for most. The cashier was an effervescent woman in her late fifties, with short, gray curly hair and an enthusiastic smile that was both genuine and contagious. She greeted each person in the line with a warm “good morning” in Hebrew, and then chatted away as she checked each item through the electronic cash register scanner. She told me how many packets she thought I’d need and then wished me a wonderful day and week, “Yom tov ve’shavua tov!”A seemingly innocuous encounter left me smiling as I walked home from the supermarket. I pondered how a brief and positive chat with a stranger had the ability to immediately improve my mood, and wondered if others she’d chatted to that morning had felt the same.