Love Your Ego to Death
The idea of not self presents a practical problem. The Buddha effectively told us to work on noticing that our sense of ourselves as selves, what we can call our egos, is a fundamental misrecognition. But until you hear the claim, you likely never thought about it at all. You just took for granted that you are who you are.
Ajahn Sumedho makes the point about not self by telling us to die before we die. This paradoxical suggestion can only mean that we should allow our egos to die before the end of our lifetimes. But the other, implicit, point is that your ego is a tenacious little bugger…