“All generalizations are false. Including this one.” So runs the central paradox in the body of wisdom known as “Rumsfeld’s Rules.” The secretary of defense under Gerald Ford (he was appointed at age 33) and George W. Bush, Donald Rumsfeld claims his rules guided the policies he championed, including launching wars against Afghanistan and Iraq. Oscar-winning director Errol Morris offers up history through the prism of the Rumsfeld Doctrine, but this is more an inquiry into the philosophy of language than an unpacking of historical fact. As The Unknown Known progresses, Morris strips bare the contradictions, obfuscations, paradoxes, and clichés at the heart of Rumsfeld’s Rules, leaving us grinning at this dazzling sparring match but far less sanguine about the fuzzy logic that propelled the United States into two lengthy, hugely costly wars. (JS)