To remember how little you matter, on a cosmic timescale, can feel like putting down a heavy burden that most of us didn't realize we were carrying i… - Oliver Burkeman

Confronting the worst-case scenario saps it of much of its anxiety-inducing power. Happiness reached via positive thinking can be fleeting and brittle, negative visualization generates a vastly more dependable calm.

Sometimes the most valuable of all talents is to be able not to seek resolution; to notice the craving for completeness or certainty or comfort, and not to feel compelled to follow where it leads.

And here lies the essential between Stoicism and the modern-day 'cult of optimism.' For the Stoics, the ideal state of mind was tranquility, not the excitable cheer that positive thinkers usually seem to mean when they use the word, 'happiness.' And tranquility was to be achieved not by strenuously chasing after enjoyable experiences, but by cultivating a kind of calm indifference towards one's circumstances.