So one should pass through this tiny fragment of time in tune with nature, and leave it gladly, as an olive might fall when ripe, blessing the earth which bore it and grateful to the tree which gave it growth.
Marcus lays out, so well, the entire summation of life. We get so worked up something that is completely out of our control. We ought to think of all those who have preceded us in death. We ought to look at history and see the utter fragility of human life, homes, cities, states, countries. All passes in time. Think no great thing of it. Accept it and embrace it. Be grateful for the life you have now rather than worrying about the life you will lose.
(see also Citadel p. 166, 276