The most fundamental principle of Stoic psychotherapy can be found in the very first sentence of the famous Enchiridion or Stoic “handbook” of Epictetus: “Some things are up to us and others are not.” The importance of this maxim and the wider implications of absorbing its meaning and implications are explored in detail throughout the ancient Stoic literature.
The Enchiridion is a condensed guidebook to Stoic life which draws upon the more lengthy Discourses of Epictetus, which claim to record discussions held between the Stoic teacher and groups of students. Just like the Enchiridion, however, the Discourses begin with a chapter dedicated to the theme: “On what is in our power, and what is not.” Epictetus begins by explaining the Stoic view that our judgements and opinions are pre-eminently within our power to control, whereas external events, especially sources of wealth and reputation, are ultimately in the hands of Fortune. Hence, the Stoic should always strive to cope with adversity by having ready “at hand” precepts that remind him “what is mine, and what is not mine, what is within my power, and what is not” (Discourses, 1.1.21). Indeed, Epictetus goes so far as to define Stoicism itself as the study of this distinction.
And to become educated [in Stoic philosophy] means just this, to learn what things are our own, and what are not. (Discourses, 4.5.7)
This distinction forms the premise for two closely-related principles. First, that the Stoic should cultivate continual self-awareness, mindful of his thoughts and judgements, as these lie at the centre of his sphere of control. Second, that he should adopt a “philosophical attitude to life”, as we now say, meaning that one should Stoically accept those things which are none of our concern or outside of our power to control. Epictetus attempts to sum up these notions in a laconic maxim of the kind which the Stoics meant to be easy to memorise and constantly “ready to hand”.
What, then, is to be done? To make the best of what is in our power, and take the rest as it naturally happens. (Discourses, 1.1.17)
Elsewhere, Epictetus expresses the same point by saying, “And thus, this paradox becomes neither impossible nor a paradox, that we must be at once cautious and courageous: courageous in what does not depend upon choice, and cautious in what does” (Discourses, 2.1.40). By “nor a paradox” he means “not contrary to commonsense”, i.e., that this advice seems strange at first but should appear self-evidently true upon reflection. Modern therapists will probably recognise this as the basis of the “Serenity Prayer”, used by members of Alcoholics Anonymous and other therapeutic and self-help approaches, which usually takes the following form,
God grant me serenity to accept the things I cannot change,
Courage to change the things I can,
And wisdom to know the difference.
It allegedly derives from a similar prayer written by the protestant theologian Reinhold Niebuhr in the 1940s (Pietsch, 1990, p. 9). However, the resemblance both to Stoic doctrine and terminology is unmistakable to anyone familiar with the literature of the subject. As it happens, courage and wisdom are two of the four cardinal virtues of classical Greek philosophy, along with self-control and justice.