Whatever be the detail with which you cram your students, the chance of their meeting in after-life exactly that detail is almost infinitesimal; and if they do meet it, they will probably have forgotten what you taught them about it. The really useful training yields a comprehension of a few general principles with a thorough grounding in the way they apply to a variety of concrete details. In subsequent practice the students will have forgotten your particular details; but they will remember by an unconscious common sense haw to apply principles to immediate circumstances. Alfred North Whitehead. The Aims of Education and Other Essays.