I have an important test in two hours and I don’t know what to do right now. Should I take a quick nap? It revitalizes the mind; a clear mind is a mind led to victory. But what if I woke up feeling only more tired, as it sometimes happens. And instead of acquiring a head more clear and ready, I am weighed down by a dense, somnolent cloud. Or maybe I should keep reading through my notes, making sure that I have every inch finely impressed in my mind. But each time I look through it, I become so bored – I’ve gone through it so many times already. It tires my mind. That is certainly not good. Then I think maybe I should just go outside and look at the skies and trees, and listen to the afternoon birds whistling. But what if I need rest?