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Name: Betty A Laliberte
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Question:
Do you believe extraterrestrial life forms exist and why do you believe this?



Replies:
Actually, sometimes I am certain they must exist, and sometimes I am certain they do not. The evidence that they do not exist is that if they did, we would probably have seen them do something or communicate with us by now (UFO's are not believable because the things UFO's do are simply not logical things one would expect intelligent aliens to do). But maybe they do exist and they know about us and they are deliberately ignoring us, or leaving us alone to figure things out for ourselves.

The big question is, we do not know how likely it is for life to begin. Simple arguments suggest that it is astronomically unlikely, so there could be only one planet in the visible universe with life on it (ours). Other arguments suggest that life began in simple stages that led very naturally to the later complex life forms (the very early algae on Earth) and that life might arise separately in many different places. We do know (or think we know) that life started only once on earth, which already makes it more probable that life is generally rare in the universe. It is possible that life began somewhere else and "seeded" the earth a few billion years ago - life started here remarkably soon after the Earth was ready for it!

A Smith


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