Here is an example of missing the point:
Even though the argument from reason may sound good, the argument is a good example of begging the question (I.E. circular reasoning). The premise (that physical sources cannot constitute a rational source) is the conclusion (That naturalism – which says physical sources can constitute a rational source – is wrong). The reason that this is hard to see initially is due to the way in which the argument is laid out.
I think this is flatly incorrect. Saying that physical causes cannot be rational is not the same as saying naturalism is false. I think it gives a good reason to reject naturalism, but it might turn out that we are not rational and naturalism is true.
The central point of the argument is that merely physical sources cannot constitute a rational source, and therefore Lewis (and others) come to the conclusion that naturalism is self-refuting. Yet this premise is left without a proper explanation, and I don’t see why merely physical sources cannot constitute a rational source – in fact, this is one of the things that naturalism argues – that rationality can arise out of a purely physical source. A person employing the Argument from Rationality simply posits as a premise that it cannot, and then claims that this makes naturalism self-refuting. Obviously, we could refute nearly any worldview in this manner. Similarly, we could claim that any abstraction – from love to opinions to ideas to art – cannot arise out of purely physical sources and our argument would be no different. Why abstractions cannot arise out of physical sources is not explained, and I think they clearly can. It’s easy to create an imaginary solution to an imaginary problem.
No, this is a clear case of missing the point. We know that at a fundamental level physical causes don’t act for reasons. The reason an asteroid hits the Earth isn’t because it thinks colliding with our planet is the best way to achieve some end. It is acting in accordance with the laws of physics, and these laws (plus relevant physical conditions) comprehensively explains the event. So we have a prima facie case against the physical constitution of rationality. Is an emergent account possible? Perhaps. Is such an account forthcoming? Doubtful. Therefore the argument constitutes a good reason to reject naturalism.
Sophistry is a joy!