While many of us recognize the expression "Pay It Forward" from the 2000 movie of that name, the concept is an ancient one. Benjamin Franklin described the process:
I do not pretend to give such a Sum; I only lend it to you. When you meet with another honest Man in similar Distress, you must pay me by lending this Sum to him; enjoining him to discharge the Debt by a like operation, when he shall be able, and shall meet with another opportunity. I hope it may thus go thro' many hands, before it meets with a Knave that will stop its Progress. This is a trick of mine for doing a deal of good with a little money.
The actual words "pay it forward" are used to describe this sequence by Robert Heinlein in a 1951 novel - perhaps the first use of this phrase.
We have reason to have infinite gratitude to the Universe for everything we have and everything we are, yet we cannot repay the Universe. We have gratitude for our distant ancestors, yet cannot repay them. We have gratitude to our parents for our very life, and to our parents or other caregivers for our nurture, yet we cannot repay them in kind. We may have many other gratitudes that, for one reason or another, cannot be repaid to those who were so generous to us.
Pay It Forward. Gift future generations in proportion to our gratitude. The nature of life is that we pay forward our biological creation and nurture. Our parents gift us with life and nurture, and we gift our children with life and nurture. While this much is essential to continued human existence, choose to take "pay it forward" farther - much farther.
Consider making "pay it forward" a way of life. As we have observed many times, expectation (demand) is always a cause of suffering. Rather than "expecting" to be repaid when we "loan" something to someone, consider the "loans" we make to be forward payments for the "loans" we received from our ancestors, nurturers and others. Request that any "loan" that we make be repaid FORWARD, when the recipient is able, and then completely forget about the "loan." It is no longer our business if, when, or how the "loan" is repaid - or is not repaid.