Now for the substance. Influenced as they were by Hume, Locke, Voltaire, etc. and the wars which resulted from religious claims to absolute truth they would not have thought it possible to escape from politics into some higher realm. Antagonistic as they were to monarchy and aristocracy they would have sought some other form. They chose democracy but were well aware of the historical precedents. They wanted to avoid the mob and the demagogue. Hence checks and balances. But they were lawyers and scholars too and knew that interpretation would always be a problem. I don't believe they thought they could rise above it to some exalted realm in this case either.
We hold these truths to be self-evident is a political statement - a statement about where they intend to begin. Like axioms. They have to start someplace and they weren't going to try to prove everything.
You make a false inference. "The Age of Voltaire" is not about French thinking but "A History of Civilization in Western Europe from 1715 to 1756 with Special Emphasis on the Conflict between Religion and Philosophy" (sub-title).
Why bother writing it down if it's not absolutely immutable? Why bother with any laws, or any theories? The fact that something is not absolutely immutable doesn't imply that it can mean anything you want it to mean. Nor does it mean instability. The founders recognized not just the problem of interpretation but the problem of stability over time. They recognized that our laws would have to change in accordance with changed circumstances and new experience. Things that could not be anticipated by human beings. So they built structures to accomodate change while retaining continuity and stability. The amendment process is one of those structures.
But by defending "interpretation" instead of "an interpretation" of a given idea, you are simply stating that a wide latitude of views can hold on plain language laws. This undermines the legislative process and, indeed, the checks and balances themselves, since it strips the legislature of their ability to legislate their intent.
We hold these truths to be self-evident is a political statement
It is a statement of philosophy: "They are self-evident. We won't argue them. Either you believe them or you're a moron." That is enough absolute truth for me.
The fact that something is not absolutely immutable doesn't imply that it can mean anything you want it to mean.
Sure it does. It's just another interpretation. You can't say it's a wrong interpretation, because that's imposing an absolute truth.
They recognized that our laws would have to change in accordance with changed circumstances and new experience.
They did no such thing! Jefferson, for one, assumed that the Constitution would not survive long. He expected another revolution. But for the time that it was in effect, it would not be twisted simply to justify the whims of jurists.
Rereading one of your many posts, I see you do agree that laws are not open to all interpretation. Your problem then is that you are inconsistent. Here you correctly understand that laws can change with the passage of new laws and that even the foundation and undergirding structure of those laws can change, as the Founders intended, through amendment.
The difficulty we have today is that Oliver Wendell Holmes has bamboozled us into thinking that interpretation can change and that the document is actually constantly changing. By using the chinanagins laid out by Holmes, his prodigees subsequently usurped our liberties, especially our freedom to make laws for ourselves.
But perhaps you are a willing slave.
in that case bahhhh...gards.