Epictetus discusses a version of this activity in Discourses 3.8 (pages 159–160 of Robin Hard’s translation); Marcus Aurelius has some encouragement in Meditations 2.1 and 10.13 (pages 17 & 136 of Gregory Hays’ translation).
Set aside a few minutes in your day—perhaps first thing in the morning, as many of the ancient Stoics suggested, or perhaps at another time which better suits your schedule. During that time, consider one affectively intense thing which might happen to you. The ancient Stoics tended to focus on things which present themselves very negatively to most ordinary people: Epictetus’ examples included the theft of a valued object (the lamp which stood at the shrine of his household Gods), and the death of one’s spouse or child. Yet Stoic tranquility does not only apply to those parts of life. There is also the challenge of remaining fixed in ourselves, in the face of affectively positive things: receiving a gift, falling in love, an unexpected windfall or promotion at work, etc. It seems to me that most of us are just as likely to be carried away by these affectively positive experiences, as by the affectively negative ones, and so I recommend alternating between apparent goods and apparent evils or harms, on different days, when using this technique.
Once you have made your selection, imagine that thing, or that event, fully and vividly, as if you were experiencing it right now. Then step back mentally, and ask yourself:
- Is this something that is up to me (that is, within my sphere of choice)?
- Does it affect my power of choice, or only my body and possessions?
- Does this appear (un)pleasant because it really is that way (for everyone, at all times), or is the sense of being (un)pleasant something which I add to it, through my own beliefs and judgments?
- If my beliefs and judgments are making the situation more (un)pleasant: Why do I hold these beliefs, and what other judgments might I choose to make?
- What choices can I make, with regard to how I respond to this event?
Take as long as you need to reflect on these questions, then imagine yourself doing whatever is within your power, to respond to the situation in the best possible way. This might involve, like Epictetus, saying “That is outside the sphere of choice, so it is nothing bad,” or “You may seem bad, but you are only an impression, not under my control.” It may involve taking actions which are under your control, in a way which preserves your freedom and integrity. Or you may see other ways of responding effectively.
Whatever response you have imagined, ask yourself, “Do I see how to maintain my integrity and freedom?”