For the past week, The World Science Festival has been showcasing the ideas, the inventions, and the hopes of some of the greatest scientific thinkers on the planet—from theoretical physicist Brian Greene and dog behaviorist Julie Hecht, to astronaut Nicole Stott and the great actor and science advocate Alan Alda.

Our own John Hockenberry was invited to moderate a number of panels during the festival, and to talk with the great Nobel laureate and theoretical physicist Steven Weinberg. 

Weinberg's newest book is called "To Explain the World: The Discovery of Modern Science." He shared insights from his new book, as well as thoughts on history, science, and the meaning of life.