Ok, so most people here would rather do insults than debate. Sad, but, thedistillers, if you're going to nick Alvin Plantinga's argument, you should at least credit him. The worker deserves his wages.
Plantinga's argument is that,
if Christianity is true,
then people can know God exists directly. That's because Christianity (or at least, Plantinga's version) says that God gives people that knowledge directly, and Plantinga's an externalist (see
http://plato.stanford.edu/entries/justep-intext/), so on his view, people can have knowledge without necessarily also being aware of the justification for it (and I suppose that, on Plantinga's Christianity, the knowledge of God is in fact a case of such knowledge). However, from what I've read, Plantinga (unlike William Lane Craig) doesn't think that this excuses you from responding to arguments against your belief, though he thinks you can have the knowledge that God exists without evidence.
Your stuff about the existence of other minds and the world not being created last Thursday (but with the appearance of age) is straight from Plantinga too. Of course, these are things we believe without evidence, if by "evidence" we mean other statements which make a hypothesis more likely than not. Plantinga says that if we think we know that other people have minds and that the world wasn't created last Tuesday, why don't we also know that there's a God?
A couple of problems: you concede that Muslims might make a similar argument to yours. But if this is so, it seems that they cannot be morally faulted for failing to worship the true God, as Romans 1 says they can. Therefore evangelical Christianity (which says Romans 1 is inerrant) is false. This is ex-apologist's objection, from his blog at
http://exapologist.blogspot.com/2010/02 ... mpkin.html.
Secondly, you've gone from paradigm cases about other minds and whatnot, which, while interesting to philosophers, are pretty uncontentious, to a claim of a direct knowledge of God, where you've already said that you don't accept the Muslims' claim. So this knowledge clearly isn't the same sort of thing as rejecting last Thursdayism, on your own argument: a claim of a direct knowledge of God is much more controversial, and knowing that others have deceived themselves, you ought to be much more careful about whether you also have. Perhaps it would be wise to seek some evidence after all? This is Chris Hallquist's objection, from his blog at
http://www.uncrediblehallq.net/2010/01/ ... l-realism/.
If you're not finding serious atheists to engage with here, I recommend those two blogs (exapologist regularly posts about Plantinga), and Luke over at Common Sense Atheism:
http://commonsenseatheism.com/.
All the best,
Paul