Knowledge results if the mind discriminates and combines things as they are united and divided in nature itself. But the important thing for education is the exercise or practice of the faculties of the mind till they become thoroughly established habitudes. The analogy constantly employed is that of a billiard player or gymnast, who by repeated use of certain muscles in a uniform way at last secures automatic skill. Even the faculty of thinking was to be formed into a trained habit by repeated exercises in making and combining simple distinctions, for which, Locke thought, mathematics affords unrivaled opportunity.
This quote from John Dewey‘s Democracy and Education (1916. Macmillan Company, New York) states the real necessity in education – practice and exercise in thinking. And contrasted with today (e.g., see here and here) identifies what is being lost by the current fascination with standardized testing.
Thinking involves combining simple distinctions and facts into larger insights and predictions. No matter the subject, this is the vocation of thinking. Car mechanics diagnosing a problem do it, engineers designing a space craft do it, plumbers installing a pipe do it, lawyers defining a case do it. Sciences or humanities or vocational school – it’s all about teaching people how to think.
(And I just love the word “habitude”.)