Carl Sagan was a famous and brilliant astronomer who was also a great speaker and presenter. He always spoke of complex issues in ways that were easy to understand and made you excited about science. He did not dumb down the issues, he simply had an engaging and unique way of putting the issue in context and illuminating and illustrating his points in a way that listeners could comprehend.

In this clip, Carl Sagan talks about the great library of Alexandria. He discusses the great written works which once existed in this library.