"People sometimes have a strong predisposition to believe things not in accordance with the facts," said Carl E. Sagan, Assistant Professor of Astronomy, speaking about intelligent life in the universe at Leverett House last night.

Sagan was referring to those "unscientific" flying saucer enthusiasts; but another position that is just as extreme, Sagan feels, is that of the average man in the street, who is determined to believe that there is no life on other planets. "This point of view was well expressed once by President Johnson, who was "relieved" to learn that the Mariner IV close-up photos of Mars showed no conclusive evidence of life there."

Questions from the audience took a different tack. One student asked how other beings would know if there was life on Earth. Aside from a few "trails of jets, wakes of ships, and logging swaths in Canada," even a near-by observer would not see any evidence of life, Sagan said.

Rock 'n' Roll

But there is another way, Sagan pointed out. "Every night, as North America swings around, an incredible barrage of radio radiation leaves the Earth, consisting mostly of the rock'n' Roll end of the broadcast spectrum and TV shows. The noise is so terrific that even several tens of light-years away, beings could detect it, and deduce that some low from of life existed here."

Another way would be to observe the traces of methane in the earth's atmosphere, Sagan said. This would puzzle them, for it cannot be explained by any ordinary process. In fact, it is largely due to emanations from the wombs of cows.

"This is very explicit evidence of life," Sagan noted, "but they could probably think of possible natural origins for the methane too."

Then one member of the audience forth-rightly inquired about mining possibilities on the moon. "This would be very expensive" Sagan replied. "Even if there are lots of diamonds on the moon, it might not pay to bring them back. If anything were mined on the moon, it would have to be something not found anywhere on earth -- perhaps some terrific hallucinogen.