Keido Fukushima: A smile, and yet not a smile
"In the world of philosophy and in the world of common sense, when something exists, it exists, and when something doesn't, it doesn't. That's the common-sense view. What makes the notion of Mu so difficult is that while everything exists, nothing exists, and while nothing exists, everything exists. Because of this profound meaning of Mu, we can't simply translate it as 'nothing.' In addition, translating Mu as 'nothing' creates a very negative impression, but the Mu of Zen includes both the affirmative and the negative. It is essential to understand this if you want to understand Zen.
If you don't comprehend this notion -that while everything exists, nothing exists, and while nothing exists, everything exists - it's very difficult to understand Buddhism, including Zen Buddhism. There are about three thousand sutras, or Buddhist sacred scriptures. The Prajnaparamita, or Perfection of Wisdom, sutras are one set of these sutras, made up of six hundred volumes. The essence of all these volumes is expressed in the Heart Sutra, and the central phrase of the Heart Sutra is while everything exists, nothing exists, while nothing exists, everything exists."
(Zen Master Keido Fukushima, 1933-2011, was head abbot of Tofukuji in Kyoto, one of the most famous Zen temples in Japan. He trained Japanese and foreigners alike, with his wit and insight. A book of his teachings, Zen Bridge: The Zen Teachings of Keido Fukushima is published by Shambhala Publications, and contains many wonderful teachings as the extract above.)