This video is part of our Brilliant Breakthroughs series: our new 20-episode mini-series exploring the “Eureka!” moments and proud accomplishments of the greatest scientific minds of our time. Join us …

Time allows us to live in the moment, reflect on the past, plan for the future. It’s our most familiar, precious, yet mysterious commodity.

What’s it like to face a faceless world? Acclaimed neurologist Oliver Sacks once apologized for almost bumping into a large bearded man, only to realize he was speaking to a mirror.

A self-driving car has a split second to decide whether to turn into oncoming traffic or hit a child who has lost control of her bicycle. An autonomous drone needs to decide whether to risk the lives of busload of civilians or lose a long-sought terrorist. How does a machine make an ethical decision?

Are we alone in this vast universe? Some think that’s highly unlikely. With new technologies joining the search, NASA estimates we’ll find definitive evidence of aliens within 20 to 30 …

Though many animals display cooperative behavior, human cooperation is distinct. Alan Alda hosts E.O. Wilson, Sarah Hrdy and other leading evolutionary biologists, anthropologists and humanitarians as they examine the origins and evolution of human cooperative behavior.