Evolutionary explanation of morality self-refuting?

[NoMoreFaith]

Given the truth of naturalism, all our beliefs, not just our moral beliefs, are the result of evolution and social conditioning. Thus, the evolutionary account leads to skepticism about knowledge in general. But this is self-defeating because then we should be skeptical of the evolutionary account itself, since it, too, is the product of evolution and social conditioning! The objection therefore undermines itself (On Guard, 2010, p. 144).

I'm sure this argument has been dealt with elsewhere but I haven't been able to find any refutations as of yet.

In order to reason, we make basic assumptions that are unfalsifiable. I'll warn you now.. this is not going to be a short answer, and I duly credit thunderf00t as a reference for these ideas.

Firstly, we assume reality exists,
Secondly, we assume we can create models on this reality which have predictive effects.

Quite simply we create a model that a rock when thrown will fly through the air and hit the ground. We can further refine this model with physics and mathematics.

So we have the assumptions that must be taken in order to reason on anything. Including God and including Evolution, and including everything in reality.
Some models are more simplistic than others, and the only way to create a model based on reality is to apply boolean operators such as "true" and "false" and to have a model with a predictable outcome that can be tested (thats not to say an outcome cannot be "mostly true" or "slightly false").

What Platinga and Craig propose here is that we must be skeptical about all things, even where we have supporting evidence, because we assume reality is real, and we assume we can build predictive models on reality.

Shocking answer; He's right. We cannot know that Evolution is real, nor can we know that your breakfast was real, or the universe is real, we can't know earth is real, or the animals, or the plants, or you. We should be skeptical about such things, however, being skeptical about the fundamental nature of reality does not allow us to answer questions about what we perceive as reality.

That is the basis of the trickery in the argument. We can easily be skeptical about everything because we make base assumption about reality and what we can predict from that reality.
The trick is equating assumption with faith in this little word game.

Why do we assume things? Because we can test their validity and they are "true enough". We know we exist, although we cannot prove it, we simply have "faith" we actually exist at all.
So the real question is, what is reasonable to have faith in as a basic structure for the universe we are able to reason in?

Atheists propose Assumption 1, and Assumption 2. What Craig and Platinga are trying to sneak in, is that God should be Assumption 3, faith without basis, just like reality and just like the ability to create predictive models.

This defies occams razor, we must take the bare minimum on faith alone, and that only include reality, and prediction based on reality. Adding God to this equation is no more sensible than adding faeries.

Evolution allows for prediction based upon the model we have created. We can predict chromosome similarities and disparities, we can predict the genetic similarity between mother and child, we can predict genetic drift, and we can predict what fossils to expect to find for the ancestors of a modern creature.

We can test these predictions based on assumption 2, and call them True, based on assumption 1, Reality.

What Craig proposes is that we should be skeptical about these assumptions, however, the argument only works in favour of "God" if you add in base assumption 3, God.
To do so is fruitless and unnecessary, when the only faith we NEED is in assumption 1 and 2.