We all know the concept of paying it forward. When someone does something for you, instead of paying it back to that person, you instead do something for another person. By doing this, the good deed spreads around the community instead of being constrained between two parties.
What is another person, exactly? A good definition is: someone other than yourself. This could be a neighbor, a friend, a family member, or even a complete stranger. But think about this: are you the same person ten years ago? Do you think that you will be ten years from now? Perhaps we can extend the definition to include you from the past or the future.