Cosmology and the mediocrity principle

[otseng]

The mediocrity principle is the philosophical notion that "if an item is drawn at random from one of several sets or categories, it's likelier to come from the most numerous category than from any one of the less numerous categories" (Kukla 2009).[1] The principle has been taken to suggest that there is nothing very unusual about the evolution of the Solar System, the Earth, humans, or any one nation. It is a heuristic in the vein of the Copernican principle, and is sometimes used as a philosophical statement about the place of humanity. The idea is to assume mediocrity, rather than starting with the assumption that a phenomenon is special, privileged or exceptional.[2][3]

http://en.wikipedia.org/wiki/Mediocrity_principle

Current cosmology assumes that the mediocrity principle is true. Our solar system, the earth, and humans are not special. But, is this assumption true? Why or why not?

[FarWanderer]

From another thread:

Please either retract your claim that the universe's beginning is evidence that Christianity is true, or accept that science saying stars existed before the earth is evidence that Christianity is false.

You mean you don't want to hear my argument of why I believe the earth existed before the stars did?

On the contrary, I'd love to hear it.

The argument starts with refuting the mediocrity principle. I created a separate thread here to discuss it:
http://debatingchristianity.com/forum/v ... hp?t=26442

I'll probably weigh in in the other thread, but I don't see how refuting the principle of mediocrity makes the the stars any younger (or the earth any older) than today's science tells us. All it would imply is that the earth is "special"- whatever that means.

So your problem remains. You need to justify taking science as authoritative regarding the universe's beginning, while simultaneously taking it as non-authoritative regarding the relative ages of the earth and stars.

Or you could always just retract your claim that Christianity is supported by how today's science tells us the universe had a beginning.

Let's discuss that in the other thread. This thread is already discussing too many unrelated issues to the OP.

OK. Go ahead. Ball is still in your court.

[Divine Insight]

We have no evidence of any life elsewhere in the universe. Therefore, life only exists on Earth. Conclusion, Earth is special because it is the only place we know of in the entire universe where life exists.

This is actually a misleading argument that conveys a false sense of knowledge.

We haven't been able to exam the entire universe at a level of detail to say whether other life exists in the entire universe. So your claim being made here suggests more knowledge than we actually possess.

For all we know other life may even exist within our very own solar system.

If you're going to use absence of evidence as evidence of absence you need to at least be able to show that you can conduct experiments that can demonstrate the absence of evidence. In this case you can't do that. You can't claim that there is no evidence in the entire universe for life save for life on earth. That implies that you were able to actually exam the entire universe and made that observation.

So your claim here goes far beyond what you are actually able to determine. Yet you state it as though it has been determined, when in fact it hasn't.

[H.sapiens]

The problem is that there was no random drawing, we were issued one planet (for now) and only one planet, special or not, we have no real way of "knowing" though it seems to be an average planet, average sun, average galaxy, etc.

[otseng]

If you're going to use absence of evidence as evidence of absence you need to at least be able to show that you can conduct experiments that can demonstrate the absence of evidence.

OK, we can even limit life to just intelligent life. The SETI program has not detected any alien intelligence.

Yet you state it as though it has been determined, when in fact it hasn't.

I'm not stating it has been determined. I'm stating that according to what we currently know, there is no evidence of any (intelligent) life existing elsewhere. Yes, there could be some life that exists on another planet, but based on current knowledge, none that we know of exist.

[otseng]

OK. Go ahead. Ball is still in your court.

I'm going to argue that the Earth is at/near the center of the universe.

A key point was raised by stcordova:

If the Big Bang is true the universe is geometrically structured under a non-Euclidean geometry that obeys the Roberston-Walker-Friedmann-Lemaitre metric -- that means the universe has no center.

If the universe on the other hand follows something like a Euclidean geometry (the one that is most familiar to everyday life), then we may potentially live in a privileged location.

Does the universe as a whole have a Euclidean geometry or a non-Euclidean geometry?

Actually, evidence points to the universe having a Euclidean geometry. The only reason people believe it has a non-Euclidean geometry is the assumption of the mediocrity principle.

Measurements determine that the universe is Euclidean (flat).

"Recent measurements (c. 2001) by a number of ground-based and balloon-based experiments, including MAT/TOCO, Boomerang, Maxima, and DASI, have shown that the brightest spots are about 1 degree across. Thus the universe was known to be flat to within about 15% accuracy prior to the WMAP results. WMAP has confirmed this result with very high accuracy and precision. We now know (as of 2013) that the universe is flat with only a 0.4% margin of error."
http://map.gsfc.nasa.gov/universe/uni_shape.html

If the universe is flat (Euclidean), then the next question is what shape is the universe? More than likely, it would be a spherical shape if it expanded from a single point of origin.

If the universe is a sphere, then the next question is where are we in this sphere? Being in the center would account for the appearance of isotropy and homogeneity.

If we are at the center, then all of the matter of the universe would've expanded from our location. Thus, it can be possible that our solar system formed before distant stars formed.

[Divine Insight]

If you're going to use absence of evidence as evidence of absence you need to at least be able to show that you can conduct experiments that can demonstrate the absence of evidence.

OK, we can even limit life to just intelligent life. The SETI program has not detected any alien intelligence.

Even SETI can hardly look at "the entire universe". I think we would be really hard pressed to detect a radio signal from intelligent life that has transmitted from even the closest galaxy, say Andromeda. And don't forget, any signals we get from Andromeda are going to have been transmitted 2.5 million years ago. Technological humans capable of transmitting radio signals are only a few centuries old. And we're in grave danger of becoming extinct already due to climate change, economic collapse, nuclear war, or who know what.

If we are typical of a technological civilization such civilizations might die off shortly after they become technological. If that's the case, they aren't likely to be sending out any continuous streams of radio signals for long periods of time.

Yet you state it as though it has been determined, when in fact it hasn't.

I'm not stating it has been determined. I'm stating that according to what we currently know, there is no evidence of any (intelligent) life existing elsewhere. Yes, there could be some life that exists on another planet, but based on current knowledge, none that we know of exist.

But you said, we are the only life existing that we know of "in the entire universe". The problem is that our current knowledge does not contain information about life the "in entire universe". So to say that we are the only life we know of "in entire universe", is purposefully misleading. It implies a level of knowledge that we don't truly possess.

[H.sapiens]

[Replying to post 25 by otseng]

SETI is a lousy experiment with its heart in the right place. For how many years of human existence have we transmitted signals in analog? Most all transmission is now digital. I expect that other life forms would move along about the same progression line. Unless SETI is listening in to the right place, during the very narrow analog window, it would detect nothing.

[FarWanderer]

OK. Go ahead. Ball is still in your court.

I'm going to argue that the Earth is at/near the center of the universe.

A key point was raised by stcordova:

If the Big Bang is true the universe is geometrically structured under a non-Euclidean geometry that obeys the Roberston-Walker-Friedmann-Lemaitre metric -- that means the universe has no center.

If the universe on the other hand follows something like a Euclidean geometry (the one that is most familiar to everyday life), then we may potentially live in a privileged location.

Does the universe as a whole have a Euclidean geometry or a non-Euclidean geometry?

Actually, evidence points to the universe having a Euclidean geometry. The only reason people believe it has a non-Euclidean geometry is the assumption of the mediocrity principle.

Measurements determine that the universe is Euclidean (flat).

"Recent measurements (c. 2001) by a number of ground-based and balloon-based experiments, including MAT/TOCO, Boomerang, Maxima, and DASI, have shown that the brightest spots are about 1 degree across. Thus the universe was known to be flat to within about 15% accuracy prior to the WMAP results. WMAP has confirmed this result with very high accuracy and precision. We now know (as of 2013) that the universe is flat with only a 0.4% margin of error."
http://map.gsfc.nasa.gov/universe/uni_shape.html

If the universe is flat (Euclidean), then the next question is what shape is the universe? More than likely, it would be a spherical shape if it expanded from a single point of origin.

If the universe is a sphere, then the next question is where are we in this sphere? Being in the center would account for the appearance of isotropy and homogeneity.

If we are at the center, then all of the matter of the universe would've expanded from our location. Thus, it can be possible that our solar system formed before distant stars formed.

Your "thus" appears to be a complete non-sequitur.

Even assuming a Euclidean universe, what does geometric location have to do with the speed of star formation?

As I've already said, I don't see how refuting the mediocracy principle is even relevant.

[scourge99]

The mediocrity principle is the philosophical notion that "if an item is drawn at random from one of several sets or categories, it's likelier to come from the most numerous category than from any one of the less numerous categories" (Kukla 2009).[1] The principle has been taken to suggest that there is nothing very unusual about the evolution of the Solar System, the Earth, humans, or any one nation. It is a heuristic in the vein of the Copernican principle, and is sometimes used as a philosophical statement about the place of humanity. The idea is to assume mediocrity, rather than starting with the assumption that a phenomenon is special, privileged or exceptional.[2][3]

http://en.wikipedia.org/wiki/Mediocrity_principle

Current cosmology assumes that the mediocrity principle is true. Our solar system, the earth, and humans are not special. But, is this assumption true? Why or why not?

What exactly in cosmology assumes the mediocrity principle?

What scientific theories would change if the mediocrity principle was neither rejected or accepted?

It seems like you are attempting to shift the burden of proof. You make the vague claim that cosmology relies on the mediocrity principle (without showing how) then demand that scientists must disprove that the universe/solar system/earth/humans are special OR that scientists must prove the mediocrity principle without explaining why.


It seems what's actually going on here is that certain theists are unwilling or unable to make a valid argument about how the universe/solar system/earth/humans is "special" so as to imply a theistic god so they try to shift the burden of proof onto others for their failure.

[otseng]

But you said, we are the only life existing that we know of "in the entire universe". The problem is that our current knowledge does not contain information about life the "in entire universe". So to say that we are the only life we know of "in entire universe", is purposefully misleading. It implies a level of knowledge that we don't truly possess.

OK, I'm not going to quibble about "in the entire universe". I'll simply state that according to what we currently know, there is no evidence of any (intelligent) life existing elsewhere. Would you agree with this statement?