Stoicism and Acceptance and Commitment Therapy: Distant Cousins
Introduction
Classic cognitive-behavioral therapy borrowed from the Stoics the idea of examining judgments and correcting distorted thoughts. Yet it left out two major pieces of the Stoic tradition: accepting what is not up to us and orienting life around core values.
Toward the end of the 20th century, those two pieces returned to psychology by another route. The American psychologist Steven Hayes and his colleagues developed Acceptance and Commitment Therapy, known by its acronym ACT. Without setting out to do so, they built an approach that in several respects resembles ancient Stoicism even more closely than classic cognitive therapy does.
ACT and Stoicism agree on the destination: a life guided by values. They differ on the path to get there.
This article explains what ACT is, how it aligns with Stoicism, where it differs, and how the two can be combined in practice.
What ACT Is
Acceptance and Commitment Therapy starts from an observation that runs counter to everyday intuition: many of our struggles come not from having painful thoughts and emotions, but from our relentless fight to avoid them. Someone who does everything possible never to feel anxiety often ends up living an increasingly narrow life.
Instead of trying to eliminate discomfort before acting, ACT proposes making room for it while taking concrete steps in the direction of what we value. It is usually described through six core processes:
1. Acceptance: stopping the war against difficult emotions and sensations. 2. Cognitive defusion: stepping back from thoughts, seeing them as thoughts rather than literal truths. 3. Contact with the present moment: paying attention to what is happening right now. 4. Self-as-context: recognizing a stable perspective from which thoughts and emotions are observed. 5. Values: clarifying what truly matters to you. 6. Committed action: taking concrete steps in the direction of those values.
Numerous meta-analyses have found ACT to be effective for conditions such as anxiety, depression, chronic pain, and addiction, with outcomes comparable to other well-established treatments.
The Parallels
Accepting What Is Not Up to Us
The Stoic discipline of desire calls for accepting what we do not control. ACT asks us to stop fighting what we cannot directly change, including thoughts and feelings that show up uninvited. Both start from the same insight: a large share of human suffering comes from resistance.
Values
For the Stoics, a good life is guided by virtue: wisdom, justice, courage, and temperance. ACT does not prescribe a universal list of virtues, but asks each person to clarify their chosen values and live in accordance with them. In both frameworks, the compass is neither pleasure nor the avoidance of pain, but what gives life meaning.
Action
Neither Stoicism nor ACT stops at reflection. The Stoics insisted that philosophy is proven in deeds. ACT places "committed action" at the center: taking concrete steps, even when they are uncomfortable.
The Present Moment
Marcus Aurelius constantly reminded himself that we live only in the present. ACT cultivates contact with the present moment as one of its foundational skills.
The Differences
Debating the Thought vs. Stepping Back from It
This is the most important difference. The Stoic examines judgments and corrects them if they are false: "Is it really true that this situation is terrible?" ACT, by contrast, focuses less on whether a thought is true or false and more on whether holding onto it is workable, proposing that we step back from it (defusion) rather than argue with it. A classic ACT technique is saying to yourself, "I am having the thought that I am a failure," instead of trying to prove to yourself that you are not a failure.
Interestingly, Epictetus's famous formula ("You are just an impression, and not at all what you claim to represent") sits halfway between the two: first it creates distance from the impression, and then it examines it.
Universal vs. Personal Values
The Stoics held that there is an objective good life for human beings, grounded in reason and virtue. ACT is deliberately neutral: each individual defines their own values, and the therapist does not tell them what those values ought to be.
A Worldview vs. a Clinical Therapy
Stoicism is a complete philosophy, encompassing a view of the cosmos, human nature, and ethics. ACT is a clinical therapy grounded in a psychological theory of language and cognition, without metaphysical claims.
A Five-Step Practice Combining Both
This exercise blends elements from both traditions:
1. Notice the difficult emotion and make room for it. Breathe and allow it to be present without fighting it (ACT). 2. Name the thought. "I am having the impression that..." (ACT and Epictetus). 3. Ask whether it is up to you. Accept what is not in your control (Stoicism). 4. Ask which value or virtue is at stake. What matters to you in this situation? (ACT and Stoicism). 5. Take one small step in that direction, bringing the emotion along if needed (both).
Common Mistakes
- Believing acceptance means resignation. In both traditions, accepting what you cannot control frees up energy to act on what you can.
- Confusing accepting emotions with tolerating every external situation. You accept internal discomfort, not necessarily an external injustice.
- Using philosophy as a substitute for therapy when clinical care is needed. ACT is a professional psychological treatment; Stoicism is a philosophy of life.
- Mixing techniques without understanding their purpose. It helps to understand how each approach works before blending them.
Conclusion
ACT brought back into modern psychology two ideas that classic cognitive therapy had left on the sidelines and that the Stoics considered essential: accepting what is not up to us and living according to what truly matters. The next time a difficult emotion shows up, try the five-step practice above. Afterward, write down which value you identified and what small step you took. If difficult emotions are persistent or overwhelming, a therapist trained in ACT or cognitive-behavioral therapy can help you work through them systematically.
References
- Hayes, S. C., Strosahl, K. D., and Wilson, K. G. (2012). Acceptance and Commitment Therapy: The Process and Practice of Mindful Change (2nd ed.). Guilford Press.
- A-Tjak, J. G. L., Davis, M. L., Morina, N., Powers, M. B., Smits, J. A. J., and Emmelkamp, P. M. G. (2015). A meta-analysis of the efficacy of acceptance and commitment therapy for clinically relevant mental and physical health problems. Psychotherapy and Psychosomatics, 84(1), 30-36.
- Epictetus. Enchiridion, 1.
- Robertson, D. (2019). How to Think Like a Roman Emperor: The Stoic Philosophy of Marcus Aurelius. St. Martin's Press.
- Vázquez, M. (2019). Invicto: Logra más. Sufre menos. Fitness Revolucionario.