Believing in intelligent alien life

[goldent]

I think this is an interesting question for the religious for two reasons:

1. The parallels to belief in God - namely the lack of any concrete evidence. I know someone (maybe Carl Sagen) said that absence of evidence if not evidence of absence. Does this apply to both God and intelligent alien life?

2. How proof of the evidence of intelligent alien life would affect your religions beliefs.

I do believe there is intelligent alien life, although I believe the argument for it is pretty weak. Having only one example (ourselves) we don't have a lot of data to work with.

I don't think proof of the evidence of intelligent alien life would affect my religions beliefs, although I guess it would depend on the circumstances.

[cbayer]

1. I think there are similarities.

And perhaps some overlap.

I don't believe we are at the top of the universal food chain, but do not (can not) know whether that more evolved entity might be something like a god or gods.

If pressed, I think many atheists would probably acknowledge that the possibility of a more evolved intelligent life form is probable. Just looking at our own amazing evolution, when you expand it to something infinite, the possibilities are, well, infinite, aren't they.

Anyway, good questions which I hope lead to some interesting discussion.

[Fortinbras Armstrong]

2. "I know someone (maybe Carl Sagen) said that absence of evidence if not evidence of absence."

It was actually John Locke. The formal term is Argumentum ad Ignorantum -- "Argument from Ignorance".

Before anyone mentions him, I should put to rest the myth that Giordano Bruno was executed for saying that there were multiple worlds with life on them. He did say that, but he also denied the divinity of Christ, the Trinity, the Virgin Birth, the presence of Christ in the Eucharist, the efficacy of the sacraments and so on; that's what got him executed for heresy, along with his being a pain in the arse. It's as if a man robbed a bank at gunpoint, shot and killed someone during the robbery, took a hostage and drove through a red light while making his getaway. The newspaper headline would not read "Man Wanted For Running A Red Light".

Incidentally, some years before Bruno, Nicholas of Cusa wrote that there may well be other worlds. He became a bishop and later a cardinal and died in his bed.

[skepticscott]

3. Unfortunately, that little ditty

"Absence of evidence is not evidence of absence" is rather misleading, if not simply false. It sacrifices accuracy to achieve a clever turn of phrase. Absence of evidence is (or at least can be) evidence of absence. What it is not is absolute proof of absence (which is rarely if ever to be found in the real world in any case). And yes, that applies to both "god" and intelligent life on other planets.

While we know that intelligent life is possible, there is no evidence as yet to show that it actually exists on other worlds. We cannot, however, even come close to examining all of the possible or predictable manifestations of such existence, so the "absence of evidence" in this case tells us very little.

As far as its effect on religious beliefs, simply discovering that alien intelligence exists would probably not affect earthly believers too much. But if we ever got to the point of actually being able to communicate with them and find out about their culture, that would be a different story.

[goldent]

4. Well, no one is claiming proof, so I don't think that is the problem

I'd say the problem is it doesn't mention the expectation (or probability) of evidence, given existence (non-absence).

Say the question is whether there is a unicorn in the room with me. Putting aside modern-physics hocus-pocus about parallel universes and 11 (12,13?) dimensions, the expectation of evidence if a unicorn was here is very high (as I can see, hear, and smell, and the room is not very big!). I can say with 100% certainty that is a unicorn where here, I would have evidence. So absence of evidence provides strong evidence of absence.

Now say the question is whether there is a unicorn on earth. Generally, we think that if this were true, we would have evidence. But we are not 100% certain - we can imagine there is a slight chance there is some very remote area where unicorns live, and no-one has seen it or reported it.

When it comes to God and Alien Life, our expectation of evidence might be much lower, using theological or scientific arguments. In this case, the statement "absence of evidence is not evidence of absence" is a valid argument, but might be very weak.

For the mathematically inclined, I think this can be shown using Bayes theorem.

[skepticscott]

5. Well, no, you can't say with

100% certainty that there is no unicorn in the room. There are always scenarios that would account for its being present, but your not detecting it (it was invisible, its odor was being masked, someone used a shrinking ray to make it too small to see, etc.). In such a limited environment, the scenarios have to be so outlandish as to defy credibility (though no more outlandish than those used to explain away supernatural/religious hokum all the time), but technically you can never be "certain", even if you can be for any practical purposes.

And yes, the broader the stage on which you want to assert "absence" the less certain you can be, though that is still different than asserting a lack of sufficient evidence to conclude "presence". But the stage for claimed evidence for "god" is much more limited than that for alien intelligence. Many religious believers assert the absence of most (or nearly all) gods, and are entirely justified in doing so.

[goldent]

6. I think you missed my point, that the expression

"Absence of evidence is not evidence of absence"

is misleading, not because of lack of absolutes, but because it fails to take into account prior knowledge about the absence of evidence. The lack of absolutes is an interesting one, but can be separated out.

In some cases, the lack of evidence is very significant, i.e. we highly expect evidence. In other cases, there are reasons we don't expect evidence (or don't know whether to expect evidence). So the lack of evidence is not so powerful.

This "prior information" (highly coveted by people working in probability theory ) is key to how valid is the statement "Absence of evidence is not evidence of absence"

[rug]

7. I remain dubious.

The main argument for extraterrestrial life is statistical: there are so many galaxies, stars and planets that one or more of them must contain life.

Going in the opposite direction, the number of factors, distance from the sun, mass of the planet, chemical proportions, etc., precisely aligned, that are needed for life results also in a statistical improbability.

The odds for an intelligent life are even higher.

I think it's a statistical push.

But if one were encountered, it would have an enormous impact on Christianity, much less so on other religions. Proof of intelligent extraterrestrial life would be proof of polygenism, the independent and separate development of intelligent species. This challenges the notion of divine intervention in creation by imparting a soul, aka intelligence, into two creatures from whom all other ensouled intelligent beings descend.

In other words, did Xenu, stranger to Adam, also have a soul?

[okasha]

8. Given that our planet

has given rise to at least two intelligent human species (sapiens and neanderthalensis) as well as intelligent non-humans (cetaceans, elephants), I'd say the odds are decidedly in favor of intelligent life on other worlds.

I doubt that proof of intelligent alien life would turn a single pagan hair, and I suspect it would be equally happily received by proponents of Process Theology. For more conventional Judeo-Christians, someone, somewhere, would be bound to point out that "the heavens declare the glory of God, and the firmament showth his handiwork."