10/21/2026
Today ( Oct 21, 2026 ), Two Arrows Zen celebrates the 83rd birthday of Michael Mugaku Zimmerman Roshi, Zen teacher, former Chief Justice of the Utah Supreme Court, and co-founder of Two Arrows Zen. His life represents an unusual intersection of American jurisprudence, Buddhist philosophy, and the transmission of Zen practice in the West.
Born in Chicago in 1943, Mugaku Roshi moved to Arizona as a teenager before attending the University of Utah, where he completed his undergraduate and legal education. His career included a judicial clerkship in Washington, D.C., private legal practice, and service on the Utah Supreme Court from 1984 to 2000, including four years as Chief Justice from 1994 to 1998. He subsequently returned to private practice, establishing Zimmerman Booher, an appellate law firm, in 2011.
Mugaku Roshi’s introduction to meditation began in 1993, during his first wife Lynne’s struggle with terminal cancer. During her illness, the couple was offered an opportunity to participate in a mindfulness meditation class drawing upon the work of Jon Kabat-Zinn, whose development of Mindfulness-Based Stress Reduction helped introduce contemplative practices into modern medicine and healthcare.
The experience introduced Mugaku Roshi to meditation during one of the most difficult periods of his life. When Lynne died in January 1994, shortly after he became Chief Justice of the Utah Supreme Court, he was left raising their three young daughters while continuing his judicial responsibilities.
In the weeks following her death, he began rising before dawn to meditate on the porch of their Salt Lake City home. What began as a way to find stability amid grief and uncertainty gradually developed into a sustained exploration of Buddhist practice.
Later, a colleague suggested that he meet Diane Hamilton, who was serving as the first director of the Utah Judiciary’s Office of Alternative Dispute Resolution. Hamilton, now Diane Musho Hamilton Roshi, had already spent more than a decade studying Buddhist teachings, beginning at Naropa University in 1983 under Chögyam Trungpa Rinpoche.
Their shared interest in meditation became the foundation of a relationship that would shape both their personal lives and their future work as Zen teachers. Hamilton introduced him to Buddhist literature, shared teachings and recordings, and encouraged him to attend an introductory class at Kanzeon Zen Center in Salt Lake City in early 1997.
During that class, a Zen monk made a statement that would become central to his understanding of Buddhist practice:
“In Buddhism, there is no hope.”
For Mugaku Roshi, the statement did not suggest despair or resignation. Rather, it pointed toward freedom from attachment to expectations and imagined futures. Instead of seeking refuge in how life might become different, Zen offered the possibility of meeting reality directly, as it is.
Together, Michael and Diane began studying under Genpo Merzel Roshi at Kanzeon Zen Center, becoming part of the White Plum lineage established by Taizan Maezumi Roshi. Their shared training would eventually lead to ordination, Dharma transmission, and the founding of Two Arrows Zen.
Mugaku Roshi’s formal training included intensive meditation, retreats, Buddhist study, and the traditional practice of kōan introspection.
Kōans, the often paradoxical encounters and questions preserved in Zen literature, are not intended to be solved through ordinary intellectual reasoning. They challenge habitual assumptions about identity, perception, and the distinction between subject and object. For someone whose professional life had been devoted to reasoning, analysis, and legal interpretation, kōan practice offered a fundamentally different approach to understanding experience.
A 2004 Deseret News profile documented Mugaku Roshi working with Zen teacher Daniel Doen Silberberg on a traditional kōan involving a buffalo passing through a window. Their exchange explored the relationship between the relative and absolute, the apparent separation of individuals, and the inseparability of personal liberation from the liberation of all beings.
His formal training progressed through several important stages. In 1998, he received Jukai, formally taking the Buddhist precepts. That same year, he and Diane Hamilton were married by Genpo Roshi.
In 2003, Mugaku Roshi and Musho Roshi received Shukke Tokudo together, becoming ordained Zen monks in the Sōtō tradition. During the spring practice period of 2005, they served together as Shushos, head students undergoing an intensive period of leadership and training.
In early 2006, Mugaku Roshi received Denkai, the transmission of the precepts, followed by Dharma transmission (Shiho) from Genpo Merzel Roshi on December 9, 2006, seven months after Musho Roshi received her transmission. The ceremony formally recognized him as a successor in the Zen teaching lineage.
In 2018, he received Inka, the final seal of recognition, from Sidney Musai Walter Roshi, another successor in the White Plum lineage of Taizan Maezumi Roshi.
His Buddhist name, Mugaku, meaning “no learning,” reflects an important distinction in Zen between intellectual knowledge and direct realization. It does not reject scholarship or study but points toward an understanding that cannot be reached through concepts alone.
Throughout his teaching, Mugaku Roshi has emphasized the fluidity of perspective, the impermanence of fixed identities, and the relationship between wisdom and compassion. His writings describe Zen as a process of recognizing the limitations of our assumptions and learning to respond to life without becoming confined by them.
This understanding has informed his work beyond the zendo. Alongside Musho Roshi, he has presented programs on meditation, mindfulness, and conflict resolution for members of the legal profession, bringing Buddhist insights into conversations about professional responsibility and human relationships.
Following their Dharma transmission in 2006, Mugaku Roshi and Musho Roshi began developing the teaching community that became Two Arrows Zen. Their early retreats in Torrey, Utah, eventually led to the establishment of a permanent zendo near Capitol Reef National Park. By 2010, Mugaku Roshi was also teaching Zen in the basement of their Salt Lake City home, and in 2011 the community opened the Artspace Zendo.
Today, Two Arrows Zen provides meditation, traditional Zen training, Dharma study, retreats, and online opportunities for practitioners throughout the world. Its approach maintains the forms and disciplines of Zen while recognizing that spiritual practice must also be integrated into family life, professional responsibilities, and the ordinary circumstances of being human.
This year marks the twentieth anniversary of Mugaku Roshi’s Dharma transmission, an occasion that recognizes his continued commitment to teaching and the generations of practitioners who have contributed to the growth of Two Arrows Zen.
On his 83rd birthday, we extend our gratitude to Mugaku Roshi for his dedication to the Dharma, his years of teaching, and his service to the sangha.
HAPPY BIRTHDAY, MUGAKU ROSHI!
As we celebrate Mugaku Roshi’s birthday and twenty years of teaching, we invite our community to honor this milestone by contributing to the Two Arrows Zen 20th Anniversary Fundraiser. Your generosity will help sustain our practice, support our teachers, and ensure that the teachings remain available to future generations.
Two Arrows Zen has reached the halfway point of its $60,000 anniversary fundraising goal. On November 22, practitioners and friends around the world will gather for a 20-hour Sit-A-Thon dedicated to the benefit of all sentient beings.
For those wishing to honor Mugaku Roshi’s birthday, please consider making a donation to help sustain the practice, programs, retreats, and teachings of Two Arrows Zen.
https://twoarrowszen.app.neoncrm.com/campaigns/two-arrows-zen-sit-a-thon-2026
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SOURCES AND FURTHER READING
Michael Mugaku Zimmerman Roshi — Two Arrows Zen
https://twoarrowszen.org/teachers/michael-mugaku-zimerman-roshi/
Our History — Two Arrows Zen
https://twoarrowszen.org/about/history/
Sitting Judge: Retired Utah Chief Justice Finds His Way as a Buddhist Monk — Deseret News, April 24, 2004
https://www.deseret.com/2004/4/24/19824855/sitting-judge-retired-utah-chief-justice-finds-his-way-as-a-buddhist-monk/
Utah Justice Now Zen Teacher — Deseret News, December 16, 2006
https://www.deseret.com/2006/12/16/19991282/utah-justice-now-zen-teacher/
Michael Mugaku Zimmerman Roshi — White Plum Asanga
https://whiteplum.org/membership-list-public/user/225/