On a year that is ending, we often cast a furtive glance. Don't linger too long. You never know how many things you've forced yourself to bury in memory might pop up again, like those impromptu, rude and irritating pop-ups on the Internet. The exercise that can be performed is to concentrate very strongly to extract the important events; the events that will make it possible to understand why they mattered so much; how they turned out to be decisive. It is also important not to lose sight of when the event occurs.