Last episode: Who Speaks for Earth?
In this final episode, Dr. Carl Sagan reviews the previous episodes and how they relate to each other. What has history taught us? How did we get to the level of understanding we're at now? What's the best way to increase our knowledge of the Cosmos in the future? There have been big mistakes made by mankind in the past and as our knowledge increases our mistakes could lead to our destruction. How can we avoid that? He discusses the murder of Hypatia, the female scientist of ancient Alexandria, and the destruction of the Library of Alexandria, which was once the largest in the world. Dr. Sagan points out how vulnerable the Earth is to the toxic substances mankind churns out on a regular basis. The greenhouse effect, pollution, and nuclear weapons affect the earth, and have the capacity to damage the ecobalance, perhaps forever. He then brings up the subject of time travel, and winds up with his favorite topic, searching for life elsewhere in the universe.
Aired: Sunday December 21, 1980

12. Encyclopedia Galactica	Dec 14, 1980	0 Reviews	10.00
11. The Persistence of Memory	Dec 7, 1980	0 Reviews	9.68
10. The Edge of Forever	Nov 30, 1980	0 Reviews	9.62
9. The Lives of the Stars	Nov 23, 1980	0 Reviews	9.70

Jonathan Fahn - Jean-Francois Champollion Ted Turner - Himself Carl Sagan - Himself (host) Jaromír Hanzlík - Johannes Kepler Robert H. Goddard - Himself