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Um, ya we do. Its "gravity".

Dark Matter & Energy are just placeholders for the "its".

Edited, Dec 1st 2010 2:25pm by Omegavegeta

Dark matter is the most likely and thus leading theory on the effect being described based on observation. It's more likely than modified gravity, and that will not change no matter how much you repeat it.

"most likely"? That's an asinine statement given the fact that there's no direct evidence of either. You might as well tell me it's the consensus theory so it must be right.

The point being that we have no points of data to work from except our one world. There can be a kajillion planets out there but if the chance to have life form is one-in-a-kajillion (or even one-in-two-kajillion) then there's no reason to assume any of them, statistically, would have life aside from Earth. If the chance is one in six then there's statistically (kajillion/6) planets with life.

So what's the chance? We have no idea. And there is no reason yet to assume that it's any closer to 1:6 than 1:(2*kajillion).

...or to accept it yet as plausible, much less probable.

That's an oversimplified view of statistics and the natural sciences. We already have strong evidence that the chance for life is greater than one. Even if you were to argue that it's not definitive, the fact that we with our insignificant powers of perception and data about the universe have even caught of glimmer of it means that, amplified magnitudes beyond our data, it has most likely happened elsewhere.

Only one is required for the theory to hold, and it doesn't even have to be a current one. Stars died before our civilization began.



Actually, having next to no data, that's exactly what it means. Hell, even I acknowledge a certain (extremely low) probability of a god.

The fact that we have that much in light of how little data we have is significant on its own. The fact that the universe is a big place (not just big, but inconceivably big) isn't meaningless at all. The bigger it is, the less likely that earth and life are special, because there is nothing identifiably innately special about the earth or life.



It's not about what one wishes is true in the first place. I get your point, I really do. But statistical likelihood is calculable (albeit not nearly perfectly) in ways other than twice-observed events. If we assume any normality about the universe, it is unlikely that earth and life are outliers all on their own.

i.e., That there IS one among so many on its own suggests the likelihood of others (again, assuming normality), even letting alone any other evidence, including highly specious evidence. It's not as tautological as it sounds-- rare events are rare. They are more rare than normal events. Until shown otherwise, we are more likely to be a normal phenomenon.

But more to the point, when you have no data or next to no data, you have multiple hypotheses that have yet to be rejected. So it is fallacious to dismiss one as ridiculous or implausible given that you've yet to even begin to collect data to prove that assertion (our current sampling is essentially zero at this point). To claim that it's ridiculous to substantiate a hypothesis without data is fine-- I am only talking about likelihood of the hypothesis being true. What you're suggesting is rejecting a hypothesis (and therefor favoring another) based on a lack of data when we haven't really even had an opportunity to collect substantial data for ANY of the hypotheses. The amount of affirmative data isn't so different from proof of evolution, as I've pointed out. We have never observed macro-evolution, either.

Meh, you overestimate my enthusiasm for sure. I have next to no interest in theories about aliens. I'm just raising the point.

As for your statements about normalcy, there's a difference between statistical normalcy and a majority. The vast majority of lifeform births don't result in micro-evolution. However, micro-evolution is a statistical normality in nature.

The vast majority of the natural world can be explained with bell curves atop bell curves. It's just a little misguided to make an a priori assumption that "planet's with life" would be the exception given that no significant data collection has even taken place. Should it go the other way? Not really. We just shouldn't dismiss it so readily when it's still an equally viable theory.

It's not a theory, it's a hypothesis at best. Joph may be stretching the point when he says we have no data that points to life elsewhere (we do have inconclusive data which could swing either way), but he's right. You can't go saying "There's life elsewhere. You can't prove there isn't. It's just as viable as a theory!"

Occam's Razor

The test for life on Mars reported inconclusive results. There are metabolic-like processes in Mars's soil. I'm not sure if this test was repeated with the newer Mars rovers, though. There are also metabolic-like processes happening on the surface of Titan. Neither of these can be held to any concrete answer, as it's more likely it's just some other surface process, but it can go either way in both situations.

Well that's where you and I have to disagree fundamentally. Alien life would be a natural occurrence, whereas god is "magic." One has an undetermined likelihood of existing naturally, the other is probably an invention of certain earthly cultures.

It's a little sad that in our culture, religion warrants so much less skepticism than the idea of life elsewhere. Human egoism at its best.



I know the difference; I just explained how it was a hypothesis earlier. I was using the term "theory" colloquially, where the two are interchangeable. If you're going to be technical, then you should read it as "hypothesis," yes. I almost changed it but didn't figure that anyone would be pedantic enough to call me on it.

As for Occam's Razor, it's not a law of science, physics, or anything really. It's not even very useful, because simplicity is itself a subjective and contextual notion. e.g., at one time the simplest explanation was that the world was flat, due to our perceptions of gravity. A theory should be simple for it to be useful as a heuristic, and that's the best we can say. There is absolutely no basis for assuming that reality should be consistent with the simplicity of human conceptions.



And we have never observed macro-evolution. There's a stark similarity between the two as theories; that being that they both would occur on a scale that modern science could not even hope to observe in the time that it has existed, and likely will not observe for centuries still. The difference is that we are embedded in the observations pertinent to evolution, while we are light years away from the observations pertinent to life elsewhere.

Again, you can't make a statement about the lack of an observed event when you haven't even really looked. Let me offer an analogy. Suppose you grew up in a tiny village and you never left it. In that village, there was a single pond with fish in it. Someone comes along and shows you a picture of the earth, and explains that there are countless ponds on the planet, but he has only seen five others, and they have no fish. Would it be more reasonable to assume that other ponds had fish, or dismiss it on the basis that you had never observed another pond with fish in it? What are the odds that your village's pond is special-- the one and only source of fish, and that those fish didn't come from another pond somehow?

This is a fundamental flaw in the ways humans conceive of ideas like simplicity and likelihood.



Evidence like what? We have inference based on microevolution, and not a lot else. Statistical inference can substantiate legitimacy to the likelihood of life elsewhere. Evolution doesn't even necessarily have that benefit (on earth). If an evolutionary biologists were as reliant on observation as you insist in this case, they would have to conclude "Gee, must have happened at some point."

The degree to which it could be called "not remotely the same thing," is that in terms of scale, with macroevolution observations being limited by time, and life elsewhere being limited predominantly by space and also possibly time, you're right-- it's not remotely the same thing. Macro-evolution has a much greater chance for observation and exactly as many incidents of it.

And this is why I jumped onto a position I don't normally support myself. Some people who embrace ID do so specifically because they hope to use it to convince others that their own "sea dragon" is real. The science of ID (such as the studies discussed on the link earlier in the thread) isn't about disproving evolutionary processes, but examining alternative explanations to life here on Earth. And given the massive gaps in evidence for long term macro-evolution *and* the somewhat incredible machinations which it's adherents have to go through to make the science "fit" the observations, it's not completely out of the realm of reasonableness to look at any of a number of alternatives.


And just because some people do latch onto ID in order to promote their own vision of that alternative doesn't mean that the work is invalid. In the same way that the fact that some people latch on to evolution as a means to push their own anti-religious agenda does not make evolution false. The science is what it is, it tells us what it tells us, and its value is placed based on how well we can test and reproduce those findings in some meaningful and useful way.


I disagree with the ID adherent that insists that since evolution can't explain everything, it must have been some intelligence, and that intelligence must have been the exact God that he believes in. But I similarly disagree with the evolution adherent that insists that since God can't be proven to exist, that it must have been evolution, and only a specific method of evolution which he happens to believe in. In both cases, people are putting what they want to be true ahead of what the science actually tells us.


I don't really care which is true. I honestly don't. It's why my arguments in this area seem so inconsistent. I'm arguing *against* people who insist that it can only be their answer which must be right. And since all sides seem to do this, I end out arguing against all sides.