There's an arguments that creationists (among others) like to make concerning the origin of life in the universe (and occasionally extrapolating it to the creation of the universe). The argument is such that, for whatever reason, the universe appears to exist in such a way that it favors life. This argument is usually present in a way similar to the following forms:
Life exists in the universe because it was designed intentionally to contain life.
If the universe (and the laws that govern it) were any different, life wouldn't exist, ergo the universe must have been conceived specifically to support (almost always human) life.
The fact that we can observe the universe means that we exist in the only universe in which life could exist.This is not the core fundamental part of the anthropic principle, but these are the type of arguments typically made by those supporting creationism (among other things). I simply wish to point out some of the fallacies that exist in these arguments, perpetually put forth by people who don't seem to care what fallacies are.
So let's start with the third concept, that life exists because it could only exist in this universe. Already we can see, perhaps, the fallacy at hand here. The simplest fallacy is that we don't have enough information to know if life can only exist here. We don't even have a good working definition for what life is yet, but we are getting closer. Either way, the point remains. There doesn't appear to be any reason that there can't be an infinite number of other universes with exactly the same laws as this one. Similarly, in our own universe, 99.9999...% of the space that exists is toxic to any life that lives on earth.
Thus, we can clearly see, having absolutely no other universe to compare to ours. If the laws are indeed different, then we likely never will. If they are the same, then it'll be exceptionally difficult to observe them also. Thus, it is impossible to say what the constraints are that life can exist within.
Let's move on to the larger fallacy that exists here. The idea that the universe is (supposedly) designed. This exists in the absence of the evidence of a creator. If it exists in the same place as those other universes (that is, not in our universe), then it will be completely independent thereof. In other words, a designer could no more design our universe without existing in it, than could another universe. We have exactly as much evidence that another universe is affecting our laws as a designer is: none. If it doesn't exist within our universe, then it can have no effect on our universe. This is one of the basest things we can observe.
For example, the moon is tidally locked to the earth, and is the primary actor upon the tides of the ocean. If somehow a thing from another universe were to suddenly change those tides, then by definition it would no longer be outside of our universe. Similarly, if it has an effect on our tides (read: the properties of our physical universe), then we can measure that effect. So far we have no evidence of a creator, nor of a second moon popping into existence to control our tides from time to time.
Furthermore, if such an occurrence did happen, we would have to rewrite the entire laws of reality to accommodate it. So far as we have observed, gravity has never been affected by anything not existing in our universe, and the laws that govern gravity reflect this. So far as we can tell, these laws have not been violated by anything supernatural (that means outside of nature, literally not in this universe).
But let's also go one step further here. Some people claim that the anthropic principle (as argued above) defends the belief in their god over others, but this is also patently false. Let's even presume (for the sake of argument) that the universe is designed by a creator. This simple fact would not lend credence to any one religion over another, and would rule out all current religions that we are aware of. The bible certainly got the earth encased in a crystal with Sheol wrong. Anyone who argues that there can be only one designed universe definitely has to deal with various Central American, Native American, Northern European and African myths whereby this universe wasn't the first one created, and certainly wasn't created 13 billion years ago. The bible and Koran would certainly have to redact any creation story involving a creation period of shorter than a few billion years. Stars don't form in a week.
This also leads to a further fallacy often committed by the religion, whereby they perceive the idea of design to lend credence to a specific god. Remember, you can't show us this creator. If you can't show evidence for why Yahweh makes a more compelling substrate for reality than Yggdrasil or Tiamat, then you can't assert it. If one says 'look at the design, therefore Jesus,' one is also saying 'look at the design, therefore Yggdrasil, the tree that holds nine worlds.' This is a tenuous argument, mostly because of the burden of proof. A person cannot claim that Yggdrasil holds up the nine worlds any more than a person can claim that Allahweh (allah+yahweh) made it. Also, Ken Ham, if you read this, I've got a post right here that says I'm right and you are wrong.
And lo, acce245 was right about everything. It's in text right here. You can't argue with that. He's got a blog post that says he's right. He must be right.
Also, anyone who happens to agree with me, feel free to quote that one.
See you all next time.