Two ordinary people suddenly go insane together. It’s a premise we enjoy from a safe distance—because surely it could never be us. I’m not so sure. Shared madness isn’t rare, it isn’t aberrant, and it sits a lot closer to ordinary love than we’d like to think. Strip away the spectacle and what’s left is the most common thing in the world: two lonely people who found a home in each other.

• Folie à deux: the madness of two — the article that inspired this lecture.
• Four models of psychopathology — how we decide what counts as “abnormal”, and why a benign shared delusion slips past all of it.
• The loneliness epidemic and Explaining group dynamics — why social isolation is so dangerous for us.
• It’s Not Social Media, Life Is Just Worse — a companion lecture on modern isolation.
• Successful Prophets — the same connection mechanism scaled from the pair to the group.

• Ursula and Sabina Eriksson (the Swedish sisters).
• Folie à deux; Jules Baillarger, Charles Lasègue and Jean-Pierre Falret.
• Shared psychotic disorder (the undiagnosis quote), and the intimacy-in-isolation qualification.
• The Japanese family case (shared delusional hallucination); delusional parasitosis; shared pseudocyesis.
• The Tromp family (BBC, Mamamia).
• Theranos: Elizabeth Holmes, Sunny Balwani, and Bad Blood.
• Group polarisation and risky shift.
• Gang-stalking, Morgellons, and mass psychogenic illness.

Meditation is the one practice everyone agrees on. It’s on the NHS, in schools, in every influencer’s guide to life, and the pitch is always the same: good for you, good for everyone, can’t hurt. Two of those three are false. It can hurt, it isn’t for everyone—and once you see what it actually is underneath the cushion, you realise you’re probably already doing it.

• Meditating for fun and for profit — the article that inspired this lecture.
• The Scientific Ritual — the first lecture in this arc, on science as a belief system.
• In Praise of the Sage — the second, on why we trust doctors the way we trust gurus.
• Positive Intelligence — one of the wellbeing-program takedowns mentioned up top.
• It’s not ‘just’ a placebo — on why “all in the head” is the point, not the problem.
• Not brain regions, brain networks — where the harms of mindfulness for some populations come up again.
• Overengineering calming down — the companion takedown of the calm-down-advice genre.
• Spirituality of Mind — more on the contemplative tradition meditation was lifted from.

• Farias, M. & Wikholm, C. (2015). The Buddha Pill: Can Meditation Change You? Publisher page.
• Van Dam, N. T., Targett, J., Davies, J. N., Burger, A. & Galante, J. (2025). Incidence and predictors of meditation-related unusual experiences and adverse effects in a representative sample of meditators in the United States. Clinical Psychological Science. Article.
• Schlosser, M., Sparby, T., Vörös, S., Jones, R. & Marchant, N. L. (2019). Unpleasant meditation-related experiences in regular meditators: Prevalence, predictors, and conceptual considerations. PLOS ONE. Article.
• Lindahl, J. R., Fisher, N. E., Cooper, D. J., Rosen, R. K. & Britton, W. B. (2017). The varieties of contemplative experience: A mixed-methods study of meditation-related challenges in Western Buddhists. PLOS ONE. Article.
• Farias, M., Maraldi, E., Wallenkampf, K. C. & Lucchetti, G. (2020). Adverse events in meditation practices and meditation-based therapies: A systematic review. Acta Psychiatrica Scandinavica. Article.
• Kabat-Zinn, J. (1982). An outpatient program in behavioral medicine for chronic pain patients based on the practice of mindfulness meditation. General Hospital Psychiatry. Article.

The modern Western story is that real knowledge comes from science or careful reasoning, and anything else—the elder, the guru, the village wise woman—is suspect. But science and reflection themselves rest on a third, intuitive, embodied mode of knowing that we use constantly and pretend we don’t. The doctor and the guru are running on the same authority structure; the only difference is who’s allowed to wear the coat. Which means we’re picking our sages by taste instead of principle—and that’s how charlatans win.

Not sure what I’ve got against linen trousers in this episode. Quite like them if I’m honest.

• In praise of the sage
• The scientific ritual (lecture)
• Mundane cults (lecture)
• It’s not ‘just’ a placebo
• Useful pharmacology
• How some psychics use psychology to screw you (Forer)
• AI hallucination is just man-guessing
• Moral blindspots
• Successful prophets
• Everything is ideology
• The charismatic leader (Weber)

• Aristotle, Metaphysics
• John Dewey, Experience and Nature
• Richard Dawkins, TED: Militant atheism
• Bertram Forer, The fallacy of personal validation
• Phenotypic drug discovery
• Yann Martel, Life of Pi