pica - my friend actually can teach anything, except I think he specialised in art and history, knew stuff about economics and maths, too, whilst teaching art he talked about philosophers, politics, etc., got them to argue in class - I still go down there and literally sit at his feet and let him talk or allow him to show me his latest books and discoveries he's made.
Re your student: I am guessing, but to just have one or a few of such successful students - and who knows how some of the seeds you have sewn in the minds of the lesser-gifted - fared? - must make you happy and you must look back on your career as having been a worthy one. I think teachers are precious - without them we wouldn't have a civilisation. Tau
