Experienced sportsmen tell us that the best moment to shoot partridges is when they rise out of the corn. It is more difficult to hit them in free flight. In like manner the point of departure seems to be the best moment to seize an analytic impression or idea. Once we miss it, it is not much use to pursue it with the devices of conscious reflection. It has already moved too far from the ground of the unconscious, like the partridges a few minutes after their upward flight. And any sportsman will be able to teach us that by this delay we lose much more than the single partridge. In the same way, if we allow the point of departure to slip by unused, whole chains of ideas and thoughts may be lost.