The distinction between knowing how and knowing that has an odd status. It is one of Professor Ryle's best known ideas, and there seems widespread agreement, in which I share, that it is a substantial contribution. But where has it been put to work, in a more than corroborative or decorative capacity, by anyone else? Who has troubled to explain the distinction carefully and accurately, when it is obvious, as I will show, that Ryle himself did not? At one time there was a suggestion in the air that the distinction opened a third way through an objectivist-subjectivist dilemma in ethics.¹ The possibility, however important, has been neither explored nor discredited. In other fields, I a constant drizzle of allusions to the distinction sinks I into the ground without substantial effect on the arguments in hand. Even in a sensible attempt, like Scheffler's,² to apply the distinction in the theory of education, the attentive reader, interested in the nature of learning and teaching, must find himself baffled by scraps of linguistic fact. We can know how but not believe how, believe in but not know in—where does that leave us?