Abstract
It is surprising that contemporary philosophers of education have paid so little attention to the question of what kinds of things can and cannot be taught. That this question is central in the history of the subject, beginning with the Meno, need not, I think, be argued. Neither should it be necessary to argue that it is logically prior to such large questions as those concerning the aims of education, or the definition of the teacher, or the relationship between democracy and education, or the place of education in nature, or, more modestly, in culture. How one could begin to answer such questions without first exploring the boundary between the teachable and the non-teachable is far from clear.