Gretchen Rubin explains:

A thoughtful reader sent me the link to a conversation between Arianna Huffington and Sheryl Sandberg, about Arianna Huffington’s book Thrive.  (To see an interview I did with Arianna Huffington, look here).

In the email, the reader said, “They talked about your story! 26 minutes in. “

Well, it’s not 100% clear that, at minute 26, they were specifically referring to my story, The Years Are Short, but the description certainly fits. And of everything that I’ve ever written, that short video story — with its single sentence, “The days are long, but the years are short” — seems to resonate most deeply with people.

If you’ve never seen it, above is my one-minute video, The Years Are Short.

And here's the Sheryl-Arianna interview:

Sam Altman of YCombinator used Gretchen's quote:

http://blog.samaltman.com/the-days-are-long-but-the-decades-are-short