You cannot live a perfect day without doing something for someone who will never be able to repay you.
I was thinking about the universe wanting to be noticed, and how I had to notice it as best I could. I felt that I owed a debt to the universe that only my attention could repay, and also that I owed a debt to everybody who didn’t get to be a person anymore and everyone who hadn’t gotten to be a person yet.
To the generous mind the heaviest debt is that of gratitude, when it is not in our power to repay it.