No activity can be successfully pursued by an individual who is preoccupied … since the mind when distracted absorbs nothing deeply, but rejects everything which is, so to speak, crammed into it. Living is the least important activity of the preoccupied man; yet there is nothing which is harder to learn… Learning how to live takes a whole life, and, which may surprise you more, it takes a whole life to learn how to die.
And taking care of our time and attention:
People are frugal in guarding their personal property; but as soon as it comes to squandering time they are most wasteful of the one thing in which it is right to be stingy.
(via Brain Pickings)