What can political philosophers learn from the practitioners of politics?
What seems to work in theory need not work in practice, yet, what works in practice necessarily must work in theory, even if the theory is mysterious to the political philosophers in question. In this way, the attempt of the practice of politics serves the attempt at its theory in two ways: as a check, a means to test empirically and materially, whether the ideals of a given theory of politics are indeed airtight, and as an archive, from which a philosophical history of politics can be conceived and written.
As a test, the practice of politics (and its practitioners) are meant to show whether certain ideals are really feasible when implemented, or, conversely, whether they contain their own contradiction, and so cannot stand. This is to grant in part, perhaps, Marx's theory of a materialist or historical dialectic -- in which the material and economic conditions (and with them the practice of politics) -- themselves produce their own antitheses -- rising or falling based on their own inherent consistency. For instance, as the rise of the bourgeoisie was a more coherent and powerful economic system than the systems of Feudal Europe which produced it, so all ideologies and practices of politics will be equally tested. In this regard, we see every theory of politics, every political philosophy, as a bet, which can only be settled by nature.
However, it should also be noted that, by this theory of politics, the Marxian theory of the historical dialectic (at least in its strong form), has itself been refuted by historical practice: the ideals of the great communist republics, in practice, turned on themselves, and ate their own tails. Communism, as practiced, contained its own contradiction. And since Communism, for Marx, was merely the implication of the theory of materialist and historical dialectic, it follows (at least by Marx's own logic), that a materialist historical dialectic cannot be a complete account of history.
To follow this point a little further, without entirely losing our way, consider a related argument: every change in the material conditions of a society must have been preceded either by an advance in technology, or in organization of that society. Advances in technology, as changes in human organization, are fundamentally ideal, since they are the arranging of nature into an order, perceived by human beings. Proof of this is that humans advanced from a state of nature without fundamentally changing their biology whereas the other animals did not. Hence, from the beginning, material dialectic follows change in ideals.
Does this refute our previous argument (that the practice of politics serves first as a check on intellectual arrogance and the errors of reason)? Not in the slightest. For although the strong version of the theory of a materialist dialectic contains its own contradiction, the weak version -- that there is some form of materialist dialectic, that to some extent, changes in the material, socioeconomic conditions of people affect their religions, governments, and values, such that political practice can serve as a check on validity on the airy castles that political philosophers naturally build -- this weak version stands strong. All that must be granted is that (1) the material, properly speaking, is the ideal manifesting in history, or more simply, that human beings build tools, and alter their environment to suit their (real or imagined) needs, and that (2) the effects of ideas when manifested as material are of a different class than the effects of ideas when not manifested. Put another way, we must only grant that theory is meaningfully different from practice, but hold that both are still different manifestations of the same thing.
Hence, on the one hand, the practice of politics has the same effect on its theory, as testing a solution to a math problem by its application in engineering: if the problem was well understood, well-implemented, and nonetheless fails in application, then there was a problem with the problem. Likewise, a theory that passes both theoretical scrutiny, and achieves its stated aims in practice has a double-guarantee of believaility (if not of its truth). And hence, practice and practitioner test, in a way of thought orthogonal to theory, the validity of theory.
Such is the case when theory and practice agrees, or when practice failing shows theory and its theoreticians to be insufficient. But what about when practice despite the protestations of all theory, nonetheless succeeds at achieving its stated ends? For instance, what of the idea of America, as considered in the light of Burke's Reflections on the Revolutions in France? For if, as Burke argued, liberal revolutions of the french variety, which flaunted and upturned the Conservative, Monarchist norm, were in fact doomed to failure, what answer was there for the success a few years prior of the Americans? Such cases, provide, I contend, the necessity of a philosophical history of politics, and such instances, the archive. For there, the test of nature, has shown us, that despite our denying calculations, nonetheless some deeper order must maintain, and therein we must learn of it. That is, when our guesses are wrong, we must see why they were wrong. Hence the political philosopher must also be an historian of, both of men, following Thucydides, and of constitutions, following Aristotle, and, indeed, following Homer, of Gods.
I will take one moment to note that the theory of practice that I am laying out here is therefore also a theory of practitioners. For, insofar as politics is the ordering of human beings (especially other human beings) for their own good (whatever that good may be), every theory of politics must also include a theory of human nature. As such, if one or the other practitioners of politics fails to accord with that theory, to that extent it is as much a refutation of the theory as if another broader and less soulful practice of politics had failed.
What, then, can political philosophers learn from the practitioners of politics? in short, they can learn whether what they say and prophesy is true or not -- they can see whether their theories hold, and whether they have correctly descried the book of Nature. For in politics as in everything else, in theory, theory and practice aren't always the same, but in practice, they are.