Tammy Heinsohn (left) and Carolyn Wilson sing in the meditation room of Alive Hospice in Nashville. They're part of the Threshold Choir, which sings to the dying. Emily Siner/Nashville Public Radio hide caption

itoggle caption Emily Siner/Nashville Public Radio

Given how little we understand about the roots of consciousness, it simply doesn't make a whole lot of sense to make commitments one way or the other when it comes to questions of what exactly dies and how. Duncan P. Walker/iStockphoto hide caption

itoggle caption Duncan P. Walker/iStockphoto

To children the world is a vast experiment, a laboratory of how things interact with one another. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Dr. Jim Olson meets with Carver Faull at Seattle Children's Hospital in August. Carver, now 12, had surgery to remove a brain tumor in 2012. Matthew Ryan Williams for NPR hide caption

itoggle caption Matthew Ryan Williams for NPR