Karl Krolow, one of the greatest postwar German poets, once wrote:
It is a long time
Since I lay so deep in sleep.
Gradually one learns once more:
Wells dry up.
A state of presence is a shallow well. Mindfulness dries up. Its half life is short. Rarely mindfulness transcends the moment that gave it birth. Therefore, it must be renewed in between the strides of our sleep-walk. The well of presence must too be watered.