A Rejoinder To "Atheism is not rational"

Brian asked me to comment on a link that asserts that Atheism is not Rational. My rejoinder follows. This started as an email and I hastily posted it to get it on the table.
I cannot afford the time to defend this as well as I should, but if any one wants to take me to task on it, there will be ample time in the future. I'm hoping that it is coherent enough that it won't need much defending.

My rejoinder to "atheism is not rational".
First lets look at what is considered rational.
Rationality is a process that uses logic and logic makes inferences from data. Inferences are correlations and experiences between objects or things whatever you want to call them. The more correlations and dependencies in a relationship between two objects the more inferences we can make about them until we can get to a point of some 'understanding' where we can make accurate predictions about it.

A large part of that process is the criteria we use for data and evidence.

As I see it, the whole debate between Christians and atheists calling each other irrational boils down to the criteria for evidence.

So now lets look at Atheism. Atheism is not subscribing to the authority of a god.
Show me what is irrational about this viewpoint.
I do not know if there is a god,
therefore I do not act like there is one
therefore I am an Atheist.

Now what is the definition of atheist? I think some want to include anti-christian or anti-religious activity in the definition but that is unwarranted.

I do not know if some crystals have healing power,
therefore I do not act as if they do,
therefore I am not a person that 'uses' crystals.

What is irrational about that?

Lets look at Christians.

- Christians assume god inspired the bible. Christians don't agree on how much inspiration that means, but some of them think it was so much that he helped write the bible in some fashion. Indeed I argue, that if a Christian does not take this position to attribute some "quality assurance" then there is no warrant to giving the bible any more authority than the Hindu Upanishads or Bagavadgita, or Islamic Quran.

Here are four assumptions that Christians must make to get Christianity off the ground.

1. Assume god exists to get him into position to help write the bible.

2. Assume that all other scripture purported to come from a god is false.

3. Assume God is the first cause when there is no precedent for any 'first cause' or "spontaneous existence"

4. And assume that the soul correlates to consciousness but does not use the brain and is not affected by any consciousness altering brain trauma. At that point why infer any correlation to consciousness at all?

Now to make these the result of a rational process, they need to follow the rational process. They are a conclusion, based on using the principles of logical inference about the relationships of data/evidence. How many correlations do the data have outside the sphere of Christianity? Not as many as the data that atheists have for their world view. How is a conclusion sound if it is based on an assumption? It is not.

There is an alternate hypothesis to how the universe got here that is based on empirical observation and inference that is consistent with the laws of physics as we understand them. Thats a lot of correlation. We can see that larger more complex things depend on smaller simpler things. This principle spans every category you can think of. It is a sound principle with many correlating examples in unrelated fields. That is its strength. Correlations across categories. It is used to make accurate non-supernatural or non-metaphysical predictions about things.

Atheists do not ascribe to any of those assumptions, and we have more strict criteria for our evidence. Our strict criteria for evidence are comparable to the strict criteria used in science and law. If you use the Christian criteria for evidence in science and law, it wouldn't work very well. Just look at how much regard the four gospels are given by Christians, and then think about how you would feel if you were convicted on testimony as uncorroborated as that.

Atheists do not make any of those assumptions. One can assert that atheists do make all kinds of assumptions till they are blue, but those are PRESUMPTIONS. They depend on Evidence in some way. And once again our criteria for evidence is different than Christians. So if the Christian wants to say that Atheism is irrational, they are saying that it is derived outside a rational process. This argument can just as easily be turned around on the Christian.

So obviously a Christian can say anything she wants to about Atheism, but she cannot say it is irrational without convicting herself.