Notionally, the simultaneity of two (or more) perspectives. Any account of irony must begin with a caveat: if irony were to be successfully defined, it would cease to be useful. The difficulty of clarifying its operations in ordinary language precisely defines the domain within which it can operate. Still, it is not wrong to say that irony involves a doubleness; and such a description, as vague as it may be, can nonetheless suggest why irony might be so important for interdisciplinary studies. The greatest risk to interdisciplinarity as an intellectual project is the collapse of its perspectivalism into a monologic METHOD. Interdisciplinarity, that is, depends upon the persistence and the discretion of its constitutive disciplines. The best interdisciplinary thinking arises not from a fusion but from a friction of methods. The interdisciplinarian, therefore, does well to be an ironist, agile among the disciplines, capable of seeing each under the aspect of the others, committed wholesale to none of them. Which is to say that interdisciplinary thinking is not more knowing than the knowledge given by the disciplines on which it depends (as it often claims to be), but less, and that is its value.