30 Phil, Chapter 13, Marcus Aurelius, Touchstone 33: Cognitive Reframing.

Cognitive Reframing: an Ancient Stoic “CBT” Technique: Cognitive reframing is a modern therapeutic technique employed in cognitive behavioral therapy (CBT) and other forms of psychotherapy, and it has its philosophical roots in ancient Stoic thought, and Zeno himself is behind it.

Emotions are not arbitrary or purely biological responses, they are rooted in your worldview and affected by the world around you. When you experience an emotion, it is often because you have made a judgment about it.