I am sure that one secret of a successful teacher is that he has formulated quite clearly in his mind what the pupil has got to know in precise fashion. He will then cease from half-hearted attempts to worry his pupils with memorizing a lot of irrelevant stuff of inferior importance.
Alfred North WhiteheadEvery philosophy is tinged with the coloring of some secret imaginative background, which never emerges explicitly into its train of reasoning.
Alfred North Whitehead