Professor of Psychology at the University of Maryland, Dr. Thomas Blass (book link) discussed the work of social psychologist Dr. Stanley Milgram, who pioneered controversial human obedience experiments. The experiments tested how people (called "teachers" in the experiment) would respond to giving what they thought were electric shocks to subjects who answered incorrectly (unbeknownst to the "teachers," the subjects were actually actors pretending to receive shocks).
The surprising revelation of the experiments was that between 60-65% of the "teachers" continuing giving out electric shocks even as they increased to what were marked as dangerous levels, because the experimenters told them they must continue. Obedience to authority was the key element, said Blass, who noted that while Milgram's work in this area raised some ethical concerns it has been quite influential, and that the US Army now offers training in how to disobey illegitimate orders.
Among Milgram's other important works was an innovative study on media violence, in which different endings of the TV show Medical Center were shown to subjects, who were then observed. He also originated the concept of "six degrees of separation" which demonstrated that it only took a small number of human links to connect any two strangers, and the "familiar stranger" theory-- that we all see certain people repeatedly that we never talk to, such as commuters on a train. Blass commented that Milgram's supposition that such strangers might begin talking with each other in the event of a tragedy was borne out in New York after 9-11.
Deep Impact Update
First hour guest, physicist James McCanney reacted to a news story which reported that NASA's Deep Impact pushed out around 250,000 tons of water when it collided into Comet Tempel 1. He disagrees with this analysis derived from X-rays and called it "a stretch of the imagination."