But ever since Plato poured himself a stiff ouzo after a hard day at the Academy, teachers have been all too aware of how challenging their profession can be.
True, we have to deal with a few things which Plato was, presumably, spared. Challenging pupils, for example, can still be those who are difficult to teach; they can also be those who come to school with machetes in their sportsbags, and spend all day text-messaging their friends having fun in the local shopping centre. (Come to that, challenging pupils could mean arranging to meet them in a deserted spot to sort out who's in charge once and for all.) Challenging conditions include being able to tell the weather by looking at it through the ceiling, or giving a course on the Symposium to a class of 35 pupils with just one copy; it can also mean having the heavy mob from Ofsted standing in the corner in their Ray-Bans, twiddling their heavy gold rings in a meaningful way.
But at heart, 'challenging' is a peculiarly British word, dripping with understatement. We talk about challenges in a school in the same way that we would describe the South Pole as a bit nippy.
Other people talk about challenges as something we have to meet. They are the sort of people who would have told Captain Scott to pack an extra jumper. Plato, of course, would have been philosophical about it, but what did he know?