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Everyone wants to leave a legacy, so what are you waiting for? There are plenty of excuses to not do what you love (and help the world along the way). But this did not stop the winners of the Purpose Prize-an award given to individuals over sixty who have followed through on their dreams of doing good.

Life (Part 2) first gets a field report on the achievements of two Purpose Prize winners: Sharon Rohrbach, a retired nurse who created a system for ensuring medical care for newborns; and Jock Brandis, a former film and television gaffer who invented a peanut-shelling machine for female laborers in Africa.

Then Robert Lipsyte sits down with Rohrbach and Brandis, along with Carol Vecchio, Executive Director of the Centerpoint Institute for Life and Career Renewal. Vecchio says most later-life achievers follow a simple formula: "Take who you are and what you love and put it together with a need out there in the world." Trusting your passion and the fearlessness that often comes later in life makes the difference.

Brandis say that even self-described "losers" like him can do a world of good. Rohrbach explains that she overcame self-doubt by forgetting about herself and focusing on the babies' lives that could be saved.

Lipsyte next talks to Harvard professor and MacArthur "genius" grant winner, Sara Lawrence-Lightfoot, who identifies what she calls a "new stage of life"-the period between middle age and old age which many of us experience as a time of reawakening and reinvention. She goes on to distill lessons from the many people she interviewed for her latest book, The Third Chapter: Passion, Risk, and Adventure in the 25 Years after 50.

Finally, publishing legend Sir Harold Evans describes how he stays young and sharp thanks to a lifelong passion for Ping-Pong.