Why wouldn't we be? If a being that was alien to us showed up here, wouldn't we be alien to them?
Ironically, in order for us to be aliens, aliens would have to exist.
But you're using two different definitions of the word. I'm sure you understand that we're talking about intelligent life beyond Earth's solar system, we're not talking about intelligent life in Earth's solar system.
Right. But a fine-tuned universe is not a god, whereas we are aliens.
No, sorry, we are not intelligent life beyond our own solar system. But we are an example of intelligent life, sure enough. The problem I see with your argument is that you're essentially saying that it's rational to believe in invisible elephants because we know something about elephants.
The difference is that the speculation with respect to aliens is based on things that actually exist.
Same with invisible elephants. It's still speculation.
Yes, indeed some of the variables are based on observation and testing hypotheses in both cases.
Then give me an example of a systematic observation of gods or a hypothesis about gods which has been tested.
The hypothesis is that a fine-tuner exists. As I said, some of the variables are based on observation, namely that the universe is fine-tuned.
Some terms are, some are not (some are based entirely on conjecture).
Right. Conjecture on the basis of systematic observation and hypothesis testing.
In both cases, some terms are based on systematic observation and hypothesis testing while other terms are based entirely on conjecture which is not based on systematic observation and hypothesis testing.
Which terms are conjecture based on faith - i.e. scientists look to their own heart, rather than to systematic observation and hypothesis testing in order to fill in the blank?
From
Wikipedia:
The value of R* is determined from considerable astronomical data, and is the least disputed term of the equation; fp is less certain, but is still much firmer than the values following. Confidence in ne was once higher, but the discovery of numerous gas giants in close orbit with their stars has introduced doubt that life-supporting planets commonly survive the creation of their stellar systems. In addition, most stars in our galaxy are red dwarfs, which flare violently, mostly in X-rays—a property not conducive to life as we know it (simulations also suggest that these bursts erode planetary atmospheres). The possibility of life on moons of gas giants (such as Jupiter's moon Europa, or Saturn's moon Titan) adds further uncertainty to this figure.
...
fi, fc and L, like fl, are guesses.
Faith is belief not based on evidence. In this case, there is no evidence that would allow one to conclude that aliens are probable, therefore to say "I believe in aliens" is not a belief based not on evidence.
If we are uncertain about the propensity of life to lead to intelligent life, then we are uncertain about the proportion of planets with life that also have intelligent life. That is, our certainty/uncertainty is equivalent to the strength of our information. Who here has suggested that we should be certain about those things for which we have scant information?
Nobody said anything about being certain. Belief that aliens are probable doesn't require certainty. But it does require more than "scant" information to be considered an evidence-based belief.
I don't think any of the terms are based on faith. That is your claim and I am waiting for you to support it.
They're not based on evidence, therefore they are based on what? A lack of evidence?
Exactly my point. The old Christian god was considered responsible for the movement of the heavenly bodies. Prior to the discovery of Gravity, that was one of the defining characteristics of God. Now that we know that Gravity is lawful and is responsible for the movement of the heavenly bodies, it no longer occurs to us to call that a defining characteristic of God.
There's a problem with your analogy if you're trying to make a comparison to the fine-tuning argument. The notion of a god being the mover of planets would be diminished if it were found that planets didn't move, just as the notion of a fine-tuner would be diminished if it was found that the universe isn't fine-tuned. But the fact that there is a natural explanation for their movement isn't quite the same thing.
I'm not a Christian, so I'm probably not a good person with which to argue Christian theology. But I do know a lot of Christians, and I don't know of any Christians who define God as "mover of the heavenly bodies." That said, God could still be responsible for the movement of the heavenly bodies even though their movement is caused by gravity, particularly if God created gravity.
Again, this supports my point. That you wouldn't consider a mouse God under those circumstances also means that you wouldn't consider whatever it was that caused a sodium of 118 to be Linda's Syndrome.
I would certainly consider a mouse God under the circumstances that one accepts the definition I posted. But again, the whole point is entirely moot because the argument concerning Linda's Syndrome doesn't produce a clearly wrong conclusion unless the premises are clearly wrong.
Please specify exactly what you think the "new evidence" is in the fine-tuning argument.
The "new evidence" is a fine-tuned universe. The argument concludes a probability of the hypothesis (that a fine-tuner exists) if a fine-tuned universe is true.
Why would you accept the probability that the guess in the premise is correct in the absence of any evidence for that guess? Would it not be considered irrational to do so?
If you consider it irrational to accept a value given in the premise because of a lack of evidence to support that value, you must also consider it irrational in an argument for the existence of intelligent aliens.
Drake's equation is meant as a framework for thinking about the possibility of communication with intelligent life. But it can't be used as an argument to make a belief in aliens "rational" without similar arguments making a belief in a god "rational."
Who is suggesting that Drake's equation can be used to support a belief based on faith in aliens?
I don't know what you mean by "a belief based on faith in aliens" but the discussion was about whether there is a reasonable definition of "irrational" that would allow belief in aliens to be considered "rational" but belief in a god "irrational."
I have suggested that the difference is belief based on scientific inquiry vs. belief based on faith. You haven't provided any examples of overlap on this point.
Both beliefs are based on arguments that depend on multiple values, some of which are based on scientific evidence and some of which are not based on evidence. You haven't provided any examples of how the two differ that would allow you to state that one is necessarily irrational and the other is rational.
Even if we concede that the universe is fine-tuned, it doesn't speak as to whether a fine-tuner, of a nature that would reasonably be considered God (remember, a heavenly body controller was found that was not considered God), is more likely than not.
That's a valid point, and was made earlier in the discussion. The argument cj posted is really about a fine-tuner of the universe. Whether or not that fits in with the beliefs of individual theists is indeed another matter. I agree, some might reject the notion that if there's a fine-tuner, that fine-tuner must be a god as assumed in the phrasing of the premise of cj's argument.
All we can do is make conditional statements. This is different from the Drake Equation, because the Drake Equation is not a tautology like Bayes' Theorem and the formula for the volume of a box are. For that reason, it avoids the circularity inherent in the fine-tuning argument for God.
I think we've pretty much run this argument into the ground and it's clear that we aren't going to get anywhere with it. An argument based on Bayes analysis is not a tautology and is not circular reasoning. If you haven't already, please read the article.
The Drake Equation is more analogous to the equation used to estimate the probability that the various physical constants would have a value that would support the development of life. Terms can be included or excluded, it's not so much about whether or not it is True but about whether or not it provides a useful estimate, it is not used to modify a pre-existing belief, etc.
It doesn't provide a useful estimate -- that's the problem. Like all arguments, the conclusions of an argument based on Drake's equation are only as valid as its premises. In this case, many of the premises are based on little or no evidence.
-Bri
