The difference is that those scientists had evience that supported their writings. While each signer of the Constitution (I think) had other writings of their beliefs, while they were behind closed doors, it is next to impossible to say, with certainty, what their intentions were with each word chosen. Because of the ambiguous language used, it appears that they wanted it to be interpretated instead of taking the document word-for-word. Certain words were left unclear, while others, that they wanted kept stable, used explicit language. That's why were left not knowing exactly what they meant in their mnds when it was written and decided upon.
Ummm. There is a ton of evidence that supports precisely what the framers of the Constitution meant. Two amendments of the Bill of Rights leap right out. The 2nd and the 10th. The 2nd was initially two amendments, which were combined because they were related. (There ARE state constitutions, rough drafts, and the Federalist Papers that explain this very thing) The 2nd amendment is routinely violated by various levels of .gov because they SAY it is vague. Bullsh*t, it's vague. "The people" does not mean the national guard. If that was true, the 1st Amendment would only apply to government owned printing presses.
The 10th amendment quite clearly prohibits the formation of things like the Federal Department of Education, but those with an agenda choose to "not understand" or claim that it is "vague." Bullsh*t, again.