“The way to live a long time – oh, a thousand years or more – is something between the way a child does it and the way a mature man does it. Give the future enough thought to be ready for it – but don’t worry about it. Live each day as if you were to die next sunrise. Then face each sunrise as a fresh creation and live for it, joyously. And never think about the past. No regrets, ever.”
Robert A. Heinlein, “Time enough for love”


Good advice… Incredibly difficult to follow on a consistent basis, but good advice nonetheless.