Merton was perhaps most interested in—and, of all of the Eastern traditions, wrote the most about—
Zen. Having studied the
Desert Fathers and other Christian mystics as part of his monastic vocation, Merton had a deep understanding of what it was those men sought and experienced in their seeking. He found many parallels between the language of these Christian mystics and the language of Zen philosophy.
[38]
In 1959, Merton began a dialogue with
D.T. Suzuki which was published in Merton's
Zen and the Birds of Appetite as "Wisdom in Emptiness". This dialogue began with the completion of Merton's
The Wisdom of the Desert. Merton sent a copy to Suzuki with the hope that he would comment on Merton's view that the Desert Fathers and the early Zen masters had similar experiences. Nearly ten years later, when
Zen and the Birds of Appetite was published, Merton wrote in his postface that "any attempt to handle Zen in theological language is bound to miss the point", calling his final statements "an example of how not to approach Zen."
[39] Merton struggled to reconcile the Western and Christian impulse to catalog and put into words every experience with the ideas of Christian
apophatic theology and the unspeakable nature of the Zen experience.
In keeping with Merton's idea that non-Christian faiths had much to offer Christianity in terms of experience and perspective and little or nothing in terms of doctrine, Merton distinguished between Zen Buddhism, an expression of history and culture, and Zen.
[38] What Merton meant by Zen Buddhism was the religion that began in China and spread to Japan as well as the rituals and institutions that accompanied it. By Zen, Merton meant something not bound by culture, religion or belief. In this capacity, Merton was influenced by the book
Zen Catholicism.
[40] With this idea in mind, Merton's later writings about Zen may be understood to be coming more and more from within an evolving and broadening tradition of Zen which is not particularly Buddhist but informed by Merton's monastic training within the Christian tradition.
[41]