The Joys of Teaching
See here for Michael Gilleland's fine post anent this topic. In a similar vein, I would add the following observations.
Teaching is the feeding of people who aren't hungry.
Teaching philosophy is the feeding of people who neither hunger nor know what food is.
Teaching is like agitating water in a glass with one's forefinger. As long as the finger is in motion, the water is agitated; but as soon as the finger is removed, the water returns to its quiescent state.
The classroom is a scene of unreality. No one takes it quite seriously. Not the students, from whom little is expected and less demanded. Not the teachers, who waste their time in discipline and remediation.
According to an apocryphal story about George Santayana, one day, while lecturing at Harvard, he suddenly intuited the absurdity of teaching. Stopping in mid-sentence, he walked out of the classroom never to return. The truth is less dramatic: he dutifully finished the semester, turned in his grades, resigned his professorship, and embarked for Rome where he spent the rest of his life in cultured retirement.