We all know academics have their peculiar obsessions, so I should have seen it coming. When I blogged about Federalist No. 9 weeks ago, I heard from a good friend at another university, a scholar of the French political philosopher Montesquieu, who upbraided me for not mentioning the great baron, whose ideas are discussed by Alexander Hamilton in that number of the Federalist. And I had gone on to mention David Hume the next day in connection with No. 10, when the Scotsman isn’t even mentioned in that essay! Yes, yes, unforgivable, I know. So this one’s for you, Paul.

In No. 47, James Madison begins a five-essay series on the separation of powers, the signal institutional arrangement of our government, and the feature of the U.S. Constitution most consistently reviled by professional academic political scientists since . . . well, since there has been a professional academic discipline of political science in the United States (since about the 1880s). Relying on “the celebrated Montesquieu” as the “oracle” on this subject, Madison pronounces on the matter categorically:

“The accumulation of all powers legislative, executive and judiciary in the same hands, whether of one, a few or many, and whether hereditary, self-appointed, or elective, may justly be pronounced the very definition of tyranny.”

Montesquieu’s Spirit of the Laws (1748) had not introduced the idea of separation of powers to political thought, but it had brought the theory to fruition in a comprehensive form most useful to our Constitution’s framers, and most recognizable to us today. But the question was, how to secure the kind of equilibrium across the three powers of government so that the “accumulation of all powers” did not occur in any one place?

Was it best simply to send each branch off about its business, rigidly assigning all responsibility for lawmaking to the legislature, for administering the law to the executive, and for adjudicating its meaning to the judiciary, then sternly admonishing each one to stick to its exclusive business? That seemed to be what some of the Anti-Federalists wanted, when they complained that the Constitution had “blended” the powers of government too much.

Consult your dog-eared Montesquieu, boys, Madison responded. When the Frenchman had examined (or more accurately, abstracted from) “the constitution of England,” which he considered “the mirror of political liberty,” he had concluded that the most effective separation of powers was one in which each branch has a “partial agency” in the business of each of the others. In short, equilibrium is maintained by checks and balances, which entail the un-separating of the branches in certain interesting ways.

Madison had more to say on this in subsequent essays. So I’ll close for now with a tangential thought of my own. Montesquieu’s favorite political order was England’s. Tocqueville’s was America. Why can’t more of the French wise up like these two?

(For explanation of this recurring feature, see here.)