Donald Robertson is the Stoic you read when you've already read the others and you're starting to wonder — okay, is there any actual evidence this stuff works, or are we just vibing on ancient quotes? Because Donald's answer to that is: yeah, it works, and there's a whole field of modern therapy built on it, let me show you.
He's Scottish originally, lives in Canada now, and his background is a pretty rare combo. He's a trained cognitive-behavioral therapist — so he's been doing actual clinical work with actual people for decades — and he's a serious classicist who's read all the ancient sources in depth. Most people in this space are one or the other. Donald is both. And the interesting thing he's spent his career doing is documenting how closely these two traditions are actually related.
Here's the thing a lot of people don't know: cognitive-behavioral therapy — which is the most widely-used, most evidence-backed form of therapy in the world right now — has direct roots in Stoicism. Albert Ellis, one of the founders of CBT back in the 1950s and 60s, explicitly credited Epictetus as his main inspiration. Same with Aaron Beck, the other co-founder. They both looked at what the Stoics were doing 2,000 years ago and basically went, "huh, this is already half a working therapy, we just need to formalize it and test it."
The specific piece they borrowed is Epictetus's core idea — that it's not events that disturb us, but our judgments about events. Which sounds philosophical but is actually the entire foundation of CBT. When a patient walks into a therapist's office and says "my life is awful," the CBT move is to separate the facts of the life from the thoughts about the life. Because the thoughts are what you can actually work with. The Stoics were doing this 2,000 years before the DSM existed.
"Men are disturbed not by the things which happen, but by the opinions about the things."
That's Epictetus. And literally every CBT textbook quotes it somewhere near the beginning. Donald's big project has been to dig underneath that borrowed quote and show, at book length, how much else the two traditions share. His book The Philosophy of Cognitive-Behavioural Therapy is the serious academic version of that argument. It's dense, it's footnoted, it's not a beach read. But it's basically the definitive text on how Stoicism became therapy.
His more popular book is How to Think Like a Roman Emperor, which came out in 2019 and is probably the best introduction to Marcus Aurelius for a general reader. It's structured as a biography of Marcus — walking through his life, the plagues, the wars, the family losses — but at every turn, Donald pauses and says, "okay, here's a technique Marcus used to get through this, and here's how a modern clinician would frame the same thing."
So you're learning history and therapy at the same time. You read about Marcus dealing with an uprising and you also learn how to do cognitive distancing. You read about him processing grief and you also learn a specific visualization exercise. The book is a two-for-one.
"You don't have to convert your feelings into beliefs."
That line, which Donald comes back to in different forms, is one of the most useful things I've picked up from his work. Because what he's pointing at is: when you feel anxious, your brain's default is to go "I feel anxious, therefore something must be actually wrong." The feeling becomes evidence. And that's where a lot of unnecessary suffering comes from. Stoicism, and CBT, both teach you to sit with the feeling without instantly believing the story it's trying to tell you.
What I love about Donald is he treats Stoicism as a technology. Not a religion. Not an aesthetic. A set of tools that have been tested in an actual clinical setting on actual people with actual distress. He's seen these techniques work on real patients — people with depression, anxiety, anger management stuff — and he's seen where they don't work and need supplementing with other approaches. He's not selling it as a cure-all. He's saying, look, here's a 2,000-year-old toolkit that overlaps a lot with the modern evidence-based one, and that's not a coincidence.
He also just released How to Think Like Socrates — extending the lineage back one more generation, because Socrates is where the Stoics learned half of their method. It's the same vibe: history and practical technique braided together.
Donald is a central figure in Modern Stoicism — the small international community of academics and practitioners who put on an annual conference called Stoicon, run an annual thing called Stoic Week where you commit to practicing the philosophy for seven days, and publish stuff in an ongoing way. Along with Massimo Pigliucci, he's basically one of the adults making sure this tradition doesn't get flattened into just hustle-culture quotes on Instagram.
He's also just nice online, which shouldn't matter but honestly does. He'll respond to random people's questions on Twitter. He'll do free Q&A sessions. He writes on Substack. He treats people asking basic questions the way a good therapist treats a first-time client — patient, real, not performative.
The reason Donald Robertson still matters to me is that he closes the loop. The Stoics wrote about how the mind works. Modern psychology tested those ideas in controlled studies. Donald is the person who's been holding both ends of that string for his entire career and showing you the continuous line.
If you've been reading the Stoics and wondering, yeah but does any of this actually change anything — Donald's the guy who can tell you. And he'll back it up with his patient records, his clinical training, and 2,300 years of philosophical backup. That combo is rare. That combo is why you read him.