WHAT WERE THE FOUNDERS' POSITIONS ON "RIGID DESIGNATORS"?

OK, I know that's an anachronism because the term didn't exist until the philosopher Saul Kripke wrote about it in 1980.  For Kripke, a rigid designator meant exactly the same thing in ALL possible worlds and "pain" is one example of such a term.

Now, did the Founders intend all the terms of the original Constitution to be rigid designators?  It seems clear to me that they didn't because that would be an unreasonable restraint on its applicability.  One example are the provisions in Section 8 for the military.  Only the Army and the Navy are mentioned but that shouldn't mean that the Air Force is unconstitutional.

Now, does this flexibility also apply to the 8th Amendment, which in part prohibits "cruel and unusual punishments"?

In some cases, we know the original meaning but the meanings of the words themselves have changed over time.  A good example is the need to revise the original King James Bible:

A major reason for revision of the King James Version, which is valid for both the Old Testament and the New Testament, is the change since 1611 in English usage. ...
The greatest problem, however, is presented by the English words which are still in constant use but now convey a different meaning from that which they had in 1611 and in the King James Version.

Thus, the King James Version uses the word "let" in the sense of "hinder," "prevent" to mean "precede," "allow" in the sense of "approve," "communicate" for "share," "conversation" for "conduct," "comprehend" for "overcome," "ghost" for "spirit," "wealth" for "well-being," "allege" for "prove," "demand" for "ask," "take no thought" for "be not anxious," etc.

I think today we would agree that what "cruel and unusual" meant in say 1791 is included in what we mean today. I also pretty sure that some of what we mean today by the phrase would not be covered under the 1791 meaning.