Many of times people show their thanks for something someone else has done for them, by doing something in return for the same person. That’s one way to make the point of being appreciative for the positive thing that someone has done for you.
But, I feel we must look at the underlining of what truly has transpired. One person has given a positive and good act that is true; usually the person giving is really not looking for something in return directly. What I mean by directly is, sure they’re looking for a return favor in an indirect way, like the person receiving should continue the trend of giving to the next person. Think about it.
Don’t you feel by giving a positive energy to someone would get its best result, when that person took what you gave in the same way you were giving and passed it on to the next person? In this way, the positive energy you gave will continue to exist and hopefully in a never-ending manner. The thought of something good shouldn’t be meant to be a concurrence of receiving because of, but a nature beginning of something that is meant to grow and live, because it came from your heart. I would definitely be thankful for that.