“Prepare for the unexpected!” they say.
This is another example of the kind of the thing done with language all the time, an utterance that doesn’t make any sense at all, but which, perhaps lamentably, everyone understands.
When we prepare for the unexpected, whatever the unexpected was before we started preparing for it is, now, of course, expected. We can only prepare for the expected.
Preparing for the unexpected is a chimera, but an interesting one because it hints at the critical distinction between training and education, between problem solving and thinking.