If the human race lasts as long as a typical mammalian species and our population continues at its current size, then there are 80 trillion people yet to come. Oxford philosophy professor William MacAskill says it's up to us to protect them. In his bold new book, "What We Owe the Future," MacAskill makes a case for longtermism. He believes that how long we survive as a species may depend on the actions we take now. --- To hear the Book Bite for "What We Owe the Future," download the Next Big Idea app at nextbigideaclub.com/app

For the last 25 years, writer A.J. Jacobs has attempted to live his life as a human guinea pig. “I’ve engaged in a series of experiments on my mind and body,” he says, “some of which have been fruitful, some humiliating failures. I’ve tried to understand the world by immersing myself in extraordinary circumstances.” His book “The Know-It-All” chronicled his experience reading the encyclopedia from cover to cover. To write “The Year of Living Biblically,” he followed every commandment in the Old Testament, including the edicts stone adulterers and avoid shaving the corners of your beard. Now A.J. is back with a new immersive memoir, “The Puzzler: One Man’s Quest to Solve the Most Baffling Puzzles Ever, from Crosswords to Jigsaws to the Meaning of Life.”  --- Want to get smart, fast? Want to hear hundreds of the world's leading authors share key insights from their books? Download the Next Big Idea app today: nextbigideaclub.com/app