I'll break with my standard practice of linkblogging to spit out something that's been bugging me for a while: Intelligent Design.
Let's look at the question: "Is the state of the natural world, in particular the existence of human beings, the result of intelligent design?". This is equivalent to "... the work of an Intelligent Designer." So far, so good, and it's all neutral inquiry.
Now we come to a fork in the road: is this Intelligent Designer part of the natural world, or not? That is, is the Intelligent Designer natural, or supernatural?
If the answer is "supernatural," then we're not doing science anymore. Go directly to theology class, do not pass Go, do not collect two hundred more freaking signatures.
If the answer is "natural," then we have to ask a whole bunch more questions about the nature of the Intelligent Designer, starting with, "Dude, what's up with the human appendix?" and moving on inexorably to "Wait, if the Intelligent Designer is a natural being, then he's bound by all the laws of nature, just like us, and, uh, where exactly did he come from?"
You can now choose again from "supernatural" and "natural"; if you finish at all, you finish on "supernatural", and we can dump all this putatively "scientific inquiry" back over on the Humanities side of the fence where it belongs.