The Essence Institute: An Exploration of Psychedelic Medicine In the Netherlands

Evan Lewis-Healey
5 min readMay 17, 2021

The founders of Essence Institute gave me some time to talk about their psilocybin truffle retreat, and their journey towards establishing Essence.

Photo by Michelle Gordon on Unsplash

The Netherlands is cementing itself as a psychedelic hub. Researchers like Kim Kuypers and Michiel van Elk are set to pioneer more groundbreaking work into the effects of psychedelics over the coming years.

The legal loophole regarding psychedelic truffles has also led to a myriad of legal retreat centres popping up all over the country. Essence is one of the most recent centres offering psilocybin truffle retreats in a legal and safe setting.

Psychedelic Roots

After being best friends for over thirty years, William Wilson and Derk Mulder founded Essence retreat in 2019. But the path to establishing Essence was a long one. Wilson set off on his journey with a degree in mechanical engineering. But, after discovering that technical stuff wasn’t for him, he pursued a career in coaching and therapy. Mulder, on the other hand, is a social organisational psychologist by training. In 2004 he established the Neurofeedback Institute, with the ultimate goal to enhance consciousness through brain stimulation methods.

Mulder points out that there has been very little progress in the field of consciousness science for decades now. “It’s really hard to pinpoint what consciousness actually is and how to make people more conscious so to speak. The only form of therapy that actually changes personality traits are psychedelics. People become more open. And so [with] all other forms of therapy…people can have a better life and learn to deal with their problems, but their essence, and their personality traits stays the same,” he told Psychedelic Spotlight.

Spurred on by the field of psychedelic research, Wilson and Mulder went on their own personal journeys. Mulder took the plunge with psychedelic truffles, and had several undoubtedly transformational journeys; after his third and most recent trip, he suddenly adopted a vegan lifestyle, too. “That’s one of the worst side effects,” he commented wryly.

Wilson on the other hand experimented with ayahuasca while it was still legal in the Netherlands. From…



Evan Lewis-Healey

PhD candidate at Cambridge University. Studying the cognitive neuroscience of altered states of consciousness.