This argument will help any of you debate a POWERFUL argument against any agnostic or atheist. 

So I've been having this extensive debate with an agnostic, and I thought you guys might like this argument.  Not gonna lie, it's pretty awesome :-).
But I do want to say it wasn't my original idea, I read it on a website, but at first it didn't make sense.  After a while it did, and I will say I got a firm grasp on it, and was able to even add some extentions of my own to it.
So here it is :-)


The universe is without purpose or reason, because it either always was without reason, or spontaneously generated without any intelligent design behind it. It continues in its existence without purpose, but entirely based upon random occurence: thus evolution, a belief system that argues for abiogenetic origin, a random compilation of materials that just so happened to form the first cell, and then evolution itself, a random set of genetic mutations that slowly produced the apex of this accidental sequence of reactions SO FAR, humanity.
Thus, the very fabric of our universe, is random chance.
Even more importantly, the composition of your brain, my brain, and every human person's brain, is a product of this random, disorderly universe, from random chance evolution.
So every person's thinking apparatus is the product of random, reasonless material.
Thus, how can you presuppose that your reasonless brain can bring you to reasonable conclusions? How can we assume that we can even come to rational conclusions, when this universe itself, and the compostion of the thing through which you are trying to come to rational conclusions, your brain, is completely irrational itself?
It makes no sense to think that your brain, which in a materialist view is just that, nothing more than material, can somehow magically surmount the disorderly, strictly material universe in which it lives, and start making rational, immaterial conjecture.
If you do believe that, you're trying to say that your materialistic brain is immaterial in nature (higher thinking) because you're saying that the brain can somehow analyze and deduce things that our outside of the very matrix in which it exists, which is complete DISORDER and IRRATIONALE.
Your brain is material, and random, purposeless material at that, existing in a purposeless universe. It lacks the very capacity to even perceive logic and order, because the universe from which it randomly evolved is completely devoid of such concepts, and thus is the brain as well, in that it has originated from said universe devoid of reason and rationale.

A main rebuttal to this would be "well people perceive their existence, and through perception of their environment, create logical order from such perception."
No, this still doesn't follow because what is perceiving, the brain, can't perceive logic and order because, for one, there is none in the universe to perceive, and secondly, it is the strict material object created from said disorderly universe, thus completely lacking the ability to perceive order by the very nature of its composition.
In short, this rebuttal is simply a misunderstanding of the argument, because it adds no new information to the premise.

And your example about the behavior of evolved humans is of no consequence, in fact, in reinforces just what I said.
In order for humankind to perceive logic and order, to logically deliberate science and our surroundings, or, as you said, to make proper decisions about the best survival of the species, we have to first have the capacity to think orderly, logically. And if our brains our simply randomly evolved material from a disorderly universe, we shouldn't even be able to pick an "ideal mate," or anything of that sort. And even if we thought we did, there'd be no way to tell, because the thing we're using to make the "good mate" decision, is itself incapable of rational choice. In fact, the statement "rational choice" would itself become an oxy-moron.

Quite simply, to think that your brain can think rationally and orderly would have to point to an ordered, purpose driven, universe, and of course the only way to have this would be if Someone intelligently designed it, and more specifically, designed the brain, allowing it to think on terms with the rational, orderly universe that shares in its Ordered, Rational Origin.