Is it impossible for God to be perfect?

Being a just and fair person is a good thing right? It's also good to be forgiving. Therefore a perfect person must express perfect justice and forgiveness, since those are both good traits to have. But surely someone who is completely just would demand justice at times when someone who is completely forgiving would forgive. Therefore, someone who is completely just and forgiving would be a self-contradictory mess. Therefore a perfect person is impossible, as this has no doubt proved, making a perfect God impossible, and therefore a perfect God cannot exist.

The above paragraph is not what I believe, by the way. The above argument has been argued at times to show that God is impossible. The reason why it's absurd is that clearly it makes sense to speak of someone as morally perfect. All they need are perfect intentions. But by placing 'justice' and 'forgiveness' into mental formulas what makes sense can be made to make no sense.

It just goes to show that our intuitions aren't very simple things that can be put e.g. into graphs and formulas. Our intuitions are very complex. So if someone tries to show that God doesn't exist using our intuitions then there's a huge danger that the intuition has been eliminated and in its place is a formula which doesn't quite capture it. I make the same general point in this article on God attribute contradiction arguments.

A doctorate could probably be written on exactly what's wrong with the above argument and the underlying principles it contradicts. We could spend a lifetime buried in philosophical books to show exactly how it's wrong. It just goes to show that we shouldn't be so quick to dismiss a concept if a formula contradicts it, if we have any reason to think that intuitively it can make sense (like the idea that there's a 'super mind' behind physical reality - i.e. God).