Oh, if He's a being with infinite qualities, there would be much about Him that's beyond comprehension. But the ID movement is driven specifically by an assumption about the nature of morality, not God. They deny that the real world provides us with the possibility of discovering any kind of objective way to judge one moral code or moral decision vs. another. I say we can look to the details of human nature to come up with good hypotheses for what the best moral codes are, and we can look to history to see what the actual results of various systems are. This is why, for instance, individual rights & the capitalist system are taking over the world instead of the various forms of collectivism.
But regardless whether God's mind is inscrutable or, um, scrutable, we would still know moral systems by their fruits.
I do not speak for all ID proponents, but Christians at least do not say that the real world does not provided us with the possibility of discovering any kind of objective way to judge one moral code or moral decision vs. another; it says there has to be a transcendent source and standard for their to be any foundation of morality at all. Mindless Evolution provides no logical basis or accounting or explanation of ethics, rationality or truth. To the extent that atheists engage in rational or moral behavior they owe to the fact that they live in God's universe. But the world-view that denies God is utterly incapable of accounting for the incumbency that one ought to do some things and not others. To say that one can come up with up with good hypotheses for what the best moral codes are presupposes a prior or higher moral standard not in evidence from a non-theistic origin.
But regardless whether God's mind is inscrutable or, um, scrutable, we would still know moral systems by their fruits.
Again, presupposing a prior or higher standard by which to judge the fruits begs the question of that standard and its origin. An impersonal chance or deterministic universe can never account for or explain the origin of moral incumbency.
Cordially,