Suppose all of humanity was infected by a virus that left us all infertile--no one will come along after us. How would you react to such a world? Agnes Callard of the University of Chicago says she would be filled with despair. But why does this seem worse than our own inevitable deaths? Callard speaks with EconTalk host Russ Roberts about the meaning of life, and what exactly about the end of humanity is so demoralizing. The conversation concludes with a discussion of whether humanity is making progress.