in a writing course. Teachers who write continually? who love, and participate in, academic discourse ? embody the values they seek to teach, and they remind themselves just how difficult such writing is, how dif ficult learning itself is. To recognize learning as diffi cult and problematic is the beginning of wisdom. Academic discourse aims at defining fields of study, defining the evidence for the study, and establishing connections between parts of the evidence. It aims, too, at systematic exposition. As Aristotle taught long ago and as the rabbis who taught the Torah and the Talmud also believed and as the medieval Scholastics and the humanists of the Renaissance assumed, sys tematic exposition is defined by the law of noncon tradiction. Nothing can be true and not true at the same time. However we may introduce our work or select the evidence to support our thinking, the fun damental aim of academic discourse is to report, ex plain, and argue in such a way that we communicate to readers something they can believe, something they will want to believe. We know, alas, that contradictions abound and that it lies beyond our power to resolve them whenever we please, that in fact sometimes we can only point them out and suggest resolutions. The essence of Hegel's di alectic, according to Walter Kaufmann, is that any sys tem of thought extended far enough begins to contradict itself (154-56). That is the point of an extraordinary essay called "Teaching 'Shakespeare,'" by my former colleague Robert N. Watson, a personal reflection on the contradictions that arise between what we know of modern criticism and what we teach in our classrooms. Academic writers cluster around the contradictions like iron fil ings in a magnetic field. We know, in short, that in every . branch of knowledge some hard, implacable, irreducible frag ments of evidence resist our ef