Harvard scientists reacted this week with much jubilation but little surprise to Tuesday's announcement that scientists working with NASA have discovered evidence that primitive life once existed on Mars.

"I'm delighted on a personal level," said Associate Professor of Philosophy Simon W. Saunders yesterday. "And I think most scientists are, and most philosophers, I hope."

Saunders--who teaches Philosophy 149: "Philosophy of Science"--echoed the opinions of his colleagues that he did not doubt that life existed elsewhere.

"It's marvelous, but not unexpected," said Agassiz Professor of Zoology Stephen Jay Gould.

Gould speculated that bacteria of the kind found in the meteorite "probably almost automatically arise when you get Earth-like conditions."

Most scientists believe that Mars was warmer and wetter about 3.6 to four billion years ago, which is the age of the fossils in the meteor. Therefore, scientists say, the odds were good that some form of life existed on the planet.

"If life is a matter of chemical reactions, then why not?" asked Professor of Biology Daniel L. Hartl.

While Hartl said he expects the short term scientific impact of the discovery to be negligible, he said its ramifications will be far-reaching.

"People today are very self-centered, and this kind of thing says 'Hey, maybe it isn't just you, your state, your country, your planet. Maybe there's more to this.'"

Alien Life

Harvard scientists agree that this week's discovery improves the chances of one day finding intelligent extraterrestrial life.

"If it is a discovery, then it certainly changes the terms of the discussion about life elsewhere in the universe; it makes it much more likely that there is life elsewhere...real life, life that we would look at--if we ever saw it--and say looks like us," said Senior Lecturer on the History of Science Peter Buck, who is also dean of the Harvard Summer School.

Saunders compared the discovery of life on Mars to the detection of planets around distant stars earlier this year. The two discoveries together, Saunders said, greatly increase the odds that intelligent extraterrestrial life exists.

"The dangerous thing is to look starkly at the letters on the wall like Daniel did, and the letters say: 'You are not unique,'" Hartl said.

"And isn't that wonderful?" he continued. "Because while it means that God did not make us unique, it also means that we are not alone."

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