For the first time since 1990 I’ve just re-read Chief Justice John Marshall’s majority opinion in Marbury v. Madison  (1803). This sentence stands out:
The powers of the legislature are defined and limited; and that those limits may not be mistaken or forgotten the constitution is written.
Note the implication: restraints on legislative power are antecedent to the written constitution. The writing of the constitutional text in which limits on the legislature’s power are explicitly spelled out does not itself create those limits. Those limits on the legislature’s power come from somewhere other than – something prior to – the process of writing the document. And enforcement of those limits is justified by something other than – something prior to – the constitution’s written text.
It follows also, from the inevitable imperfection of words, that the scope of those limits is unavoidably different from what words can convey. (I make no claim that this implication is one that Marshall drew or would draw.) So if the presumption is that the constitution is meant to constrain government power, a subsidiary presumption should be that, when in doubt, the scope of the limits on the legislature’s powers is greater than is conveyed by the words of the constitutional text.
I’m no constitutional lawyer, scholar, or historian, so I’ll venture no opinion on where John Marshall believed those limits originated – except to repeat that Marshall here quite clearly says that those limits are antecedent to (and, hence, do not derive from) the writing of the document.
Regardless of whatever origins Marshall himself identified for these limitations on legislative power, this passage strongly suggests that there is a higher, more fundamental-than-text law on which any constitution worth its ink (or pixels) must be grounded. And although I am not learned enough to know whether or not John Marshall would agree me, I would go even further and say that, at the end of the day, law cannot be created ex nihilo or from the exercise of human reason; like so much else that makes our civilization possible, law is (to steal a phrase popular with Hayek) “the result of human action but not of human design.”
Law can be recorded in words (if only imperfectly). Law can sometimes be modified at its margins with words. And word-wielding legislation- or constitution-makers can, building on the law’s general principles, create specific institutions of government (such as bicameral legislatures, age-requirements for elected officials, regular schedules for elections, and explicit prohibitions that would otherwise not exist on the exercise of government power) – institutions that, if crafted wisely, are reasonably consistent with the evolved, unwritten, deep law. But law as such evolves unplanned from the countless actions and interactions of people going about their everyday lives and forming expectations about how each other, individually and in various types of groupings, will act under a variety of different circumstances.
Commands, of course, are a very different matter. They are created, often ex nihilo, by the mind of some powerful gun-toting or armed-forces-influencing man or men – and all too often to no good end. Legislation is typically nothing more than a command.
Again, law cannot be created from scratch, from out of nothing with all prior rules and laws and norms erased or ignored, ex nihilo – not even at Constitutional Conventions attended by the wisest and most learned and public-spirited men and women of the age.