Vision asks Clive Svendsen of the Regenerative Medicine Institute at Cedars-Sinai Medical Center in Los Angeles about the current direction in stem-cell research.

What is it about human beings that makes us always want to push the limits? When it comes to the frontiers of medical science, is it possible to go too far? 

How the universe came into existence continues to intrigue—and baffle—cosmologists. Can anyone ever know how it all really began?

May 20, 2010, may one day be known as another key marker, a hinge of history in terms of the human control of life. 

Darwin seemed to understand that sometimes the more we know, the more we realize how little we know.

Even if one accepts the big-bang model on faith, obvious questions come to mind for most people: What came before the big bang?

How did Darwin’s theory of natural selection and survival of the fittest become today’s dominant worldview?

Mid-20^th-century technological advances caused many to ignore the potentially negative effects. One early voice of caution was that of Rachel Carson.

Vision interviews astronaut Michael Massimino who has traveled to space twice to help repair the Hubble Space Telescope.

Marine biologist Eric Montie discusses some of the challenges in determining the presence and effects of chemicals such as DDT in marine mammals.