Once again I am rather stunned to discover that I have always been a Stoic! This is exactly how I view things and always have, and I have to tell you it is what has allowed me to keep a relatively  level head during these tumultuous times. The below words are from William Stephens in his explanation of the Meditations of Marcus Aurelius. 
“The correct understanding of the three parts of time is this: (1) Use the past only to draw lessons about the world, yourself, and other people, which help you gain wisdom and promote the virtues; let go of wanting to change the past in any way.
(2) Don’t worry about the future, since your logos [i.e., reason] equips you with the resources for handling whatever the future brings; entrust the future to Providence and embrace whatever will happen, confident that you can deal with it virtuously.
(3) Concentrate on doing what is under your control now by exercising reverence, justice, wisdom, and all the virtues in your present circumstances.”
– William Stephens
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