Consider the co-worker who acknowledges hard work you do, and appreciates you for your effort. This acknowledgement gives this you a sense of accomplishment, which in turn makes you feel happier and better.
Consider the neighbor who offers help when he notices you have a problem with your car, or gives you advice that helps you solve your problem easier.
Consider the person who recognizes that you have a disability or health defect, and chooses to help you and provide you with positive reinforcement to help you focus on progress and feel better about your situation.
I think the article, and the notion of "positive people," is more than just throwing a word around. It's about people who add weight and meaning to their words through thoughtful consideration and genuine compassion.
I don't educate people that are not ready to be educated!